U.S. patent application number 16/929327 was filed with the patent office on 2020-11-05 for automatic display of previously-acquired endoluminal images.
The applicant listed for this patent is SYNC-RX, LTD. Invention is credited to Ran COHEN, Eldad KLAIMAN, David TOLKOWSKY.
Application Number | 20200345321 16/929327 |
Document ID | / |
Family ID | 1000004957820 |
Filed Date | 2020-11-05 |
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United States Patent
Application |
20200345321 |
Kind Code |
A1 |
TOLKOWSKY; David ; et
al. |
November 5, 2020 |
AUTOMATIC DISPLAY OF PREVIOUSLY-ACQUIRED ENDOLUMINAL IMAGES
Abstract
Apparatus and methods are provided for use with an endoluminal
data-acquisition device that acquires a set of endoluminal
data-points of a lumen of a subject's body at respective locations
inside the lumen, a second endoluminal device, and a display
configured to display images. At least one processor includes
location-association functionality that associates a given data
point acquired by the endoluminal data-acquisition device with a
given location within the lumen. Location-determination
functionality determines, by means of image processing, in an
extraluminal image of the second endoluminal device, a current
location of at least a portion of the second endoluminal device.
Display-driving functionality drives the display to display an
indication of the endoluminal data point associated with the
location, in response to determining that the portion of the second
device is currently at the location. Other applications are also
described.
Inventors: |
TOLKOWSKY; David; (TEL AVIV,
IL) ; COHEN; Ran; (PETAH TIKVA, IL) ; KLAIMAN;
Eldad; (HAIFA, IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SYNC-RX, LTD |
Netanya |
|
IL |
|
|
Family ID: |
1000004957820 |
Appl. No.: |
16/929327 |
Filed: |
July 15, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13228185 |
Sep 8, 2011 |
10716528 |
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16929327 |
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12666879 |
Mar 29, 2012 |
8781193 |
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13228185 |
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PCT/IL2011/000612 |
Jul 28, 2011 |
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12666879 |
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12650605 |
Dec 31, 2009 |
9855384 |
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PCT/IL2011/000612 |
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12666879 |
Mar 29, 2012 |
8781193 |
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PCT/IL2009/001089 |
Nov 18, 2009 |
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12650605 |
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12075244 |
Mar 10, 2008 |
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12666879 |
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61344464 |
Jul 29, 2010 |
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61344875 |
Nov 1, 2010 |
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61457339 |
Mar 3, 2011 |
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61457455 |
Apr 1, 2011 |
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61457780 |
Jun 2, 2011 |
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61457951 |
Jul 15, 2011 |
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61193329 |
Nov 18, 2008 |
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61193915 |
Jan 8, 2009 |
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61202181 |
Feb 4, 2009 |
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61202451 |
Mar 2, 2009 |
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61213216 |
May 18, 2009 |
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61213534 |
Jun 17, 2009 |
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61272210 |
Sep 1, 2009 |
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61272356 |
Sep 16, 2009 |
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60906091 |
Mar 8, 2007 |
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60924609 |
May 22, 2007 |
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60929165 |
Jun 15, 2007 |
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60935914 |
Sep 6, 2007 |
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60996746 |
Dec 4, 2007 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 6/12 20130101; A61B
2090/062 20160201; G06T 19/20 20130101; A61F 2/82 20130101; A61B
2017/22044 20130101; G06T 7/00 20130101; G09G 5/363 20130101; A61B
8/0891 20130101; A61B 6/461 20130101; A61B 2017/00252 20130101;
A61B 5/0066 20130101; A61B 2017/00694 20130101; A61B 2017/00703
20130101; A61F 2250/0096 20130101; A61B 6/5217 20130101; G06T 1/00
20130101; A61B 6/541 20130101; A61B 2017/22094 20130101; G06T
2219/2024 20130101; A61B 6/503 20130101; A61B 6/504 20130101; A61B
6/463 20130101; A61B 1/0005 20130101; G06F 3/14 20130101; A61F
2/958 20130101 |
International
Class: |
A61B 6/00 20060101
A61B006/00; G06F 3/14 20060101 G06F003/14; G06T 1/00 20060101
G06T001/00; G09G 5/36 20060101 G09G005/36; G06T 7/00 20060101
G06T007/00; G06T 19/20 20060101 G06T019/20; A61B 1/00 20060101
A61B001/00; A61B 6/12 20060101 A61B006/12 |
Claims
1. A co-registration system, comprising: a processor configured for
communication with an extraluminal imaging device, a first
endoluminal data-acquisition device, a different second endoluminal
data-acquisition device, and a display, wherein the processor is
configured to: receive an extraluminal image of a lumen of a body
of a subject; receive, from the first endoluminal data-acquisition
device operating according to a first modality and positioned at a
first location within the lumen, first endoluminal data associated
with the lumen at the first location, wherein the first endoluminal
data comprises data of the first modality; associate the first
endoluminal data with a first corresponding location of the lumen
in the extraluminal image; receive, from the second endoluminal
data-acquisition device operating according to a different second
modality and positioned at a second location within the lumen,
second endoluminal data associated with the lumen at the second
location, wherein the second endoluminal data comprises data of the
second modality; associate the second endoluminal data with a
second corresponding location of the lumen in the extraluminal
image; generate, based on associating the first endoluminal data
with the first corresponding location and associating the second
endoluminal data with the second corresponding location, a screen
display comprising: the extraluminal image; a first indication of
the first endoluminal data at the first corresponding location in
the extraluminal image; and a second indication of the second
endoluminal data at the second corresponding location in the
extraluminal image; and output the screen display to the
display.
2. The co-registration system of claim 1, wherein the first
location is different from the second location.
3. The co-registration system of claim 1, wherein the first
endoluminal data comprises an endoluminal image of the lumen at the
first location.
4. The co-registration system of claim 3, wherein the endoluminal
image comprises an intravascular ultrasound image or an optical
coherence tomography image.
5. The co-registration system of claim 3, wherein the second
endoluminal data comprises at least one of pressure, flow, or
temperature within the lumen at the second location.
6. The co-registration system of claim 3, wherein the screen
display further comprises: an endoluminal image stack comprising
the endoluminal image; and a marking associated with the first
location in the endoluminal image stack.
7. The co-registration system of claim 1, wherein the first
indication and the second indication are overlaid on the
extraluminal image in the screen display.
8. The co-registration system of claim 1, wherein the screen
display further comprises at least one of the first endoluminal
data or the second endoluminal data overlaid on the extraluminal
image.
9. The co-registration system of claim 1, wherein the processor is
configured to merge the first endoluminal data and the second
endoluminal data.
10. The co-registration system of claim 1, further comprising the
display.
11. The co-registration system of claim 1, further comprising the
extraluminal imaging device.
12. The co-registration system of claim 1, further comprising the
first endoluminal data-acquisition device.
13. The co-registration system of claim 1, further comprising the
second endoluminal data-acquisition device.
Description
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] The present application is a continuation of U.S.
Non-Provisional patent application Ser. No. 13/228,185, filed Sep.
8, 2011, now U.S. Pat. No. 10,716,528, which is a continuation of
U.S. patent application Ser. No. 12/666,879, filed Mar. 29, 2012,
now U.S. Pat. No. 8,781,193 and a continuation of International
Application No. PCT/IL2011/000612, entitled "Co-use of endoluminal
data and extraluminal imaging," filed 28 Jul. 2011, which:
[0002] (a) claims the benefit of:
[0003] U.S. Provisional Patent Application 61/344,464, entitled
"Co-use of endoluminal data and extraluminal imaging," filed 29
Jul. 2010;
[0004] U.S. Provisional Patent Application 61/344,875, entitled
"Co-use of endoluminal data and extraluminal imaging," filed 1 Nov.
2010;
[0005] U.S. Provisional Patent Application 61/457,339, entitled
"Co-use of endoluminal data and extraluminal imaging," filed 3 Mar.
2011;
[0006] U.S. Provisional Patent Application 61/457,455, entitled
"Co-use of endoluminal data and extraluminal imaging," filed 1 Apr.
2011;
[0007] U.S. Provisional Patent Application 61/457,780, entitled
"Co-use of endoluminal data and extraluminal imaging," filed 2 Jun.
2011; and
[0008] U.S. Provisional Patent Application 61/457,951, entitled
"Co-use of endoluminal data and extraluminal imaging," filed 15
Jul. 2011; and
[0009] (b) is a continuation-in-part of U.S. patent application
Ser. No. 12/650,605 to Cohen (published as US 2010/0172556), filed
Dec. 31, 2009, which:
[0010] (i) is a continuation of U.S. patent application Ser. No.
12/666,879 to Steinberg, filed Mar. 29, 2012, which is the US
national phase of PCT Application No. PCT/IL2009/001089 to Cohen
(published as WO 10/058398), filed Nov. 18, 2009, which claims
priority from the following patent applications: [0011] U.S.
Provisional Patent Application 61/193,329, entitled "Apparatuses
and methods for the automatic generation of a road map from
angiographic images of a cyclically-moving organ," to Steinberg,
filed Nov. 18, 2008 [0012] U.S. Provisional Patent Application
61/193,915, entitled "Image processing and tool actuation for
medical procedures," to Steinberg, filed Jan. 8, 2009 [0013] U.S.
Provisional Patent Application 61/202,181, entitled "Image
processing and tool actuation for medical procedures," to
Steinberg, filed Feb. 4, 2009 [0014] U.S. Provisional Patent
Application 61/202,451, entitled "Image processing and tool
actuation for medical procedures," to Steinberg, filed Mar. 2, 2009
[0015] U.S. Provisional Patent Application 61/213,216, entitled
"Image processing and tool actuation for medical procedures," to
Steinberg, filed May 18, 2009 [0016] U.S. Provisional Patent
Application 61/213,534, entitled "Image Processing and Tool
Actuation for Medical Procedures," to Steinberg, filed Jun. 17,
2009 [0017] U.S. Provisional Patent Application 61/272,210,
entitled "Image processing and tool actuation for medical
procedures," to Steinberg, filed Sep. 1, 2009 and [0018] U.S.
Provisional Patent Application 61/272,356, entitled "Image
Processing and Tool Actuation for Medical Procedures" to Steinberg,
filed Sep. 16, 2009; and
[0019] (ii) is a continuation-in-part of U.S. patent application
Ser. No. 12/075,244 to Tolkowsky (published as US 2008/0221442),
filed Mar. 10, 2008, entitled "Imaging for use with moving organs,"
which claims the benefit of U.S. Provisional Patent Application
Nos.: [0020] 60/906,091 filed on Mar. 8, 2007, [0021] 60/924,609
filed on May 22, 2007, [0022] 60/929,165 filed on Jun. 15, 2007,
[0023] 60/935,914 filed on Sep. 6, 2007, and [0024] 60/996,746
filed on Dec. 4, 2007, [0025] all entitled "Apparatuses and methods
for performing medical procedures on cyclically-moving body
organs."
[0026] The present application is related to the following patent
applications: [0027] U.S. patent application Ser. No. 12/075,214 to
Iddan (published as 2008/0221439), filed Mar. 10, 2008, entitled
"Tools for use with moving organs." [0028] U.S. patent application
Ser. No. 12/075,252 to Iddan (published as US 2008/0221440), filed
Mar. 10, 2008, entitled "Imaging and tools for use with moving
organs." [0029] U.S. patent application Ser. No. 12/781,260 to
Blank (published as US 2010/0228076), filed May 17, 2010, entitled
"Controlled actuation and deployment of a medical device." [0030]
U.S. patent application Ser. No. 12/487,315 to Iddan (published as
US 2009/0306547), filed Jun. 18, 2009, entitled "Stepwise
advancement of a medical tool," which claims the benefit of U.S.
Provisional Patent Application No. 61/129,331 to Iddan, filed on
Jun. 19, 2008, entitled "Stepwise advancement of a medical
tool."
[0031] All of the above-mentioned applications are incorporated
herein by reference.
FIELD OF EMBODIMENTS OF THE INVENTION
[0032] Some applications of the present invention generally relate
to medical imaging. Specifically, some applications of the present
invention relate to the co-use of endoluminal data and extraluminal
imaging.
BACKGROUND
[0033] Vascular catheterizations, such as coronary
catheterizations, are frequently-performed medical interventions.
Such interventions are typically performed in order to diagnose the
blood vessels for potential disease, and/or to treat diseased blood
vessels. Typically, in order to facilitate diagnosis of blood
vessels, the catheterization is performed under extraluminal
imaging. For some procedures, an endoluminal data-acquisition
device is used to perform endoluminal imaging and/or measurements.
If appropriate based on the diagnosis, a treatment is applied to
the blood vessel. For some procedures, treatment of the blood
vessel includes the application of a treatment to the blood vessel
by a therapeutic device that is placed endoluminally. For example,
a therapeutic device (e.g., a balloon) is placed in the blood
vessel temporarily and retrieved subsequent to the treatment having
been applied. Alternatively, a therapeutic device (e.g., a stent)
may remain implanted inside the blood vessel in order to treat the
blood vessel.
SUMMARY OF EMBODIMENTS
[0034] Some applications of the present invention are applied to
medical procedures performed, in whole or in part, on or within
luminal structures. For some applications, apparatus and methods
are provided for facilitating the co-use of extraluminal imaging
and endoluminal data (i.e., data that are acquired using an
endoluminal data-acquisition device), in performing medical
procedures. Endoluminal data may include imaging data (e.g.,
imaging data acquired using an endoluminal imaging probe), data
derived from measurements (e.g., measurements performed using an
endoluminal sensor or measuring device), other data, and any
combination thereof.
[0035] In accordance with some applications of the present
invention, during insertion and deployment of an endoluminal
device, e.g., an endoluminal therapeutic device, into a lumen,
real-time extraluminal images of the device inside the lumen are
displayed together with endoluminal data that were acquired
previously and that correspond to the current location of the
endoluminal therapeutic device. The cumulative effect of showing
the extraluminal images and the endoluminal data is as if the
endoluminal therapeutic tool is being inserted and deployed under
both extraluminal imaging and endoluminal data acquisition. For
some applications, the aforementioned techniques are applied since
it is difficult or impossible to acquire the endoluminal data
during insertion and deployment of the therapeutic device, because
the lumen is too narrow to accommodate both the endoluminal
therapeutic device and the endoluminal data-acquisition device.
Alternatively, although it may be possible for the lumen to
accommodate both the endoluminal therapeutic device and the
endoluminal data-acquisition device, the aforementioned techniques
may be used to prevent the endoluminal data-acquisition device from
interfering with the endoluminal therapeutic device, during
insertion and/or deployment of the therapeutic device.
[0036] There is therefore provided, in accordance with some
applications of the present invention, apparatus for use with an
endoluminal data-acquisition device that is configured to acquire a
set of endoluminal data-points with respect to a lumen of a body of
a subject at respective locations inside the lumen, a second
endoluminal device, and a display configured to display images of
the lumen, the apparatus including:
[0037] at least one processor, including: [0038]
location-association functionality configured to associate a given
endoluminal data point acquired by the endoluminal data-acquisition
device with a given location within the lumen; [0039]
location-determination functionality configured, in an extraluminal
image of the second endoluminal device, to determine by means of
image processing, a current location of at least a portion of the
second endoluminal device inside the lumen; [0040] display-driving
functionality configured, in response to determining that the
portion of the second endoluminal device is currently at the given
location, to drive the display to display an indication of the
endoluminal data point associated with the given location.
[0041] For some applications, the second endoluminal device
includes a second endoluminal data-acquisition device configured to
acquire a second set of endoluminal data-points with respect to the
lumen at respective locations inside the lumen, and the
display-driving functionality is configured, in response to
determining that the portion of the second endoluminal
data-acquisition device is currently at the given location, to
drive the display to display:
[0042] an endoluminal image acquired by the first endoluminal
data-acquisition device that corresponds to the given location,
and
[0043] an endoluminal image acquired by the second endoluminal
data-acquisition device that corresponds to the given location.
[0044] For some applications, the second endoluminal device
includes a second endoluminal data-acquisition device configured to
acquire a second set of endoluminal data-points with respect to the
lumen at respective locations inside the lumen, and the
display-driving functionality is configured, in response to
determining that the portion of the second endoluminal
data-acquisition device is currently at the given location, to
drive the display to display:
[0045] an endoluminal image acquired by the second endoluminal
data-acquisition device that corresponds to the given location,
and
[0046] an indication of the given location with respect to an
endoluminal image stack of the lumen generated using the
endoluminal data points acquired by the first endoluminal
data-acquisition device.
[0047] For some applications, the endoluminal data-acquisition
device includes an endoluminal imaging probe configured to acquire
endoluminal images of the lumen at respective locations inside the
lumen, and the location-association functionality is configured to
associate a given endoluminal image acquired by the endoluminal
imaging probe with a given location within the lumen.
[0048] For some applications, the display-driving functionality is
configured, in response to determining that the portion of the
second endoluminal device is currently at the given location, to
drive the display to display an endoluminal image that corresponds
to the given location.
[0049] For some applications, the display-driving functionality is
configured, in response to determining that the portion of the
second endoluminal device is currently at the given location, to
drive the display to display an indication of the given location
with respect to an endoluminal image stack of the lumen.
[0050] For some applications, the display-driving functionality is
configured, in response to determining that the portion of the
second endoluminal device is currently at the given location, to
drive the display to display an indication of the given location
with respect to the extraluminal image of the lumen.
[0051] For some applications, the second endoluminal device
includes a second endoluminal data-acquisition device configured to
acquire a second set of endoluminal data-points with respect to the
lumen at respective locations inside the lumen, and the
display-driving functionality is further configured, in response to
determining that the portion of the second endoluminal
data-acquisition device is currently at the given location, to
drive the display to display:
[0052] an endoluminal image acquired by the first endoluminal
data-acquisition device that corresponds to the given location,
and
[0053] an endoluminal image acquired by the second endoluminal
data-acquisition device that corresponds to the given location.
[0054] For some applications, the second endoluminal device
includes a second endoluminal data-acquisition device configured to
acquire a second set of endoluminal data-points with respect to the
lumen at respective locations inside the lumen, and the
display-driving functionality is further configured, in response to
determining that the portion of the second endoluminal
data-acquisition device is currently at the given location, to
drive the display to display:
[0055] an endoluminal image acquired by the second endoluminal
data-acquisition device that corresponds to the given location,
and
[0056] an indication of the given location with respect to an
endoluminal image stack of the lumen generated using the
endoluminal data points acquired by the first endoluminal
data-acquisition device.
[0057] For some applications,
[0058] the endoluminal data-acquisition device includes a portion
that is visible in extraluminal images of the data-acquisition
device inside the lumen, and
[0059] the location-association functionality is configured to
associate the endoluminal data point with the given location inside
the lumen by determining, by means of image-processing, in an
extraluminal image of the data-acquisition device inside the lumen,
a location of at least the visible portion of the data-acquisition
device inside the lumen, at the acquisition of the endoluminal data
point.
[0060] For some applications,
[0061] the endoluminal data-acquisition device includes an
image-acquiring portion, and
[0062] the location-association functionality is configured to
associate the endoluminal data point with the given location inside
the lumen by accounting for an offset between the portion of the
endoluminal data-acquisition device that is visible in the
extraluminal image, and the image-acquiring portion of the
endoluminal data-acquisition device.
[0063] For some applications, the second endoluminal device
includes an endoluminal therapeutic device configured to apply a
therapy to the lumen, and the location-determination functionality
is configured, in an extraluminal image of the endoluminal
therapeutic device, to determine by means of image processing, a
current location of at least a portion of the endoluminal
therapeutic device inside the lumen.
[0064] For some applications, the endoluminal therapeutic device
includes a guidewire configured to penetrate an occlusion of the
lumen and the endoluminal data-acquisition device includes a
forward-looking endoluminal imaging probe, and the
location-association functionality configured to associate the
given endoluminal data point with the given location by associating
an endoluminal image of a portion of the lumen that is distal to
the given location with the given location.
[0065] There is further provided, in accordance with some
applications of the present invention, a method, including:
[0066] acquiring a set of endoluminal data point of a lumen of a
subject's body;
[0067] determining that one of the endoluminal data points of the
set corresponds to a given location inside the lumen; and
[0068] subsequently,
[0069] while a second endoluminal device is inside the lumen:
[0070] acquiring an extraluminal image of the second endoluminal
device inside the lumen; [0071] by means of image processing,
determining, based upon the extraluminal image, a current location
of at least a portion of the second endoluminal device inside the
lumen; and [0072] in response to determining that the portion of
the second endoluminal device is currently at the given location,
displaying an indication of the endoluminal data point that
corresponds to the given location.
[0073] For some applications, the second endoluminal device
includes an endoluminal therapeutic device configured to apply a
therapy to the lumen, and acquiring the extraluminal image of the
second endoluminal device inside the lumen includes acquiring an
extraluminal image of the endoluminal therapeutic device inside the
lumen.
[0074] For some applications, the endoluminal therapeutic device
includes a guidewire, and the method further includes penetrating
an occlusion of the lumen with the guidewire.
[0075] For some applications, acquiring the at least one
endoluminal data point includes, while a forward-looking
endoluminal imaging probe is at the given location, acquiring an
endoluminal image of a portion of the lumen that is distal to the
given location.
[0076] There is additionally provided, in accordance with some
applications of the present invention, a method for use with an
endoluminal data-acquisition device configured to be moved through
a lumen of a subject's body, the endoluminal data-acquisition
device having a radiopaque marker coupled thereto, including:
[0077] while the endoluminal data-acquisition device is being moved
through the lumen, acquiring a plurality of endoluminal data points
of the lumen using the endoluminal data-acquisition device;
[0078] determining that a first endoluminal data point corresponds
to a first location within the lumen, by: [0079] acquiring a first
angiographic image of the lumen, at a time associated with an
acquisition of the first endoluminal data point by the endoluminal
data-acquisition device, and [0080] determining a location of the
radiopaque marker within the first angiographic image of the lumen,
by performing image processing on the first angiographic image, the
location of the radiopaque marker within the first angiographic
image of the lumen corresponding to the first endoluminal data
point;
[0081] determining that a second endoluminal data point corresponds
to a second given location within the lumen, by: [0082] acquiring a
second angiographic image of the lumen, at a time associated with
an acquisition of the second endoluminal data point by the
endoluminal data-acquisition device, and [0083] determining a
location of the radiopaque marker within the second angiographic
image of the lumen by performing image processing on the second
angiographic image, the location of the radiopaque marker within
the second angiographic image of the lumen corresponding to the
second endoluminal data point;
[0084] generating a combined angiographic image of the lumen that
includes representations of the first and second marker locations
thereon, by co-registering the first and second angiographic
images; and
[0085] determining that at least one location on the combined
angiographic image that is intermediate to the first and second
locations of the radiopaque marker corresponds to an endoluminal
data point acquired between the acquisitions of the first and
second data points, by interpolating between the first and second
locations of the radiopaque marker on the combined angiographic
image; and
[0086] generating an output in response thereto.
[0087] For some applications, acquiring the plurality of
endoluminal data points of the lumen using the endoluminal
data-acquisition device while the endoluminal data-acquisition
device is being moved through the lumen includes acquiring the
plurality of endoluminal data points of the lumen using the
endoluminal data-acquisition device while the endoluminal
data-acquisition device is being pulled-back through the lumen.
[0088] There is further provided, in accordance with some
applications of the present invention, apparatus for use with:
[0089] an endoluminal data-acquisition device configured to acquire
a plurality of endoluminal data points of a lumen of a body of a
subject at respective locations inside the lumen, while the
endoluminal data-acquisition device is moved through the lumen, the
endoluminal data-acquisition device having a radiopaque marker
coupled thereto,
[0090] an angiographic imaging device configured to (a) acquire a
first angiographic image of the lumen, at a time associated with an
acquisition of a first endoluminal data point by the endoluminal
data-acquisition device, and (b) acquire a second angiographic
image of the lumen, at a time associated with an acquisition of a
second endoluminal data point by the endoluminal data-acquisition
device, and
[0091] a display,
[0092] the apparatus including:
[0093] at least one processor, including: [0094]
location-determination functionality configured to: [0095]
determine that the first endoluminal data point corresponds to a
first location within the lumen, by determining a location of the
radiopaque marker within the first angiographic image of the lumen,
by performing image processing on the first angiographic image, the
location of the radiopaque marker within the first angiographic
image of the lumen corresponding to the first endoluminal data
point, and [0096] determine that a second endoluminal data point
corresponds to a second given location within the lumen by
determining a location of the radiopaque marker within the second
angiographic image of the lumen by performing image processing on
the second angiographic image, the location of the radiopaque
marker within the second angiographic image of the lumen
corresponding to the second endoluminal data point; [0097]
image-co-registration functionality configured to generate a
combined angiographic image of the lumen that includes
representations of the first and second marker locations thereon,
by co-registering the first and second angiographic images; [0098]
location-association functionality configured to determine that at
least one location on the combined angiographic image that is
intermediate to the first and second locations of the radiopaque
marker corresponds to an endoluminal data point acquired between
the acquisitions of the first and second data points, by
interpolating between the first and second locations of the
radiopaque marker on the combined angiographic image; [0099]
display-driving functionality configured to drive the display to
display an output, in response to determining that the intermediate
location corresponds to the endoluminal data point acquired between
the acquisitions of the first and second data points.
[0100] For some applications, the location-determination
functionality is configured to:
[0101] determine that the first endoluminal data point corresponds
to the first location within the lumen by determining that the
first endoluminal data point corresponds to a location in a
vicinity of a first end of a luminal segment of interest, and
[0102] determine that the second endoluminal data point corresponds
to the second location within the lumen by determining that the
second endoluminal data point corresponds to a location in a
vicinity of a second end of the luminal segment of interest.
[0103] For some applications,
[0104] the location-determination functionality is configured to:
[0105] determine that the first endoluminal data point corresponds
to the first location within the lumen by determining that the
first endoluminal data point corresponds to a location in a
vicinity of a first end of a luminal segment of interest, and
[0106] determine that the second endoluminal data point corresponds
to the second location within the lumen by determining that the
second endoluminal data point corresponds to a location between the
first end and a second end of the luminal segment of interest,
and
[0107] the angiographic imaging device includes an angiographic
imaging device that is further configured to acquire a third
angiographic image of the lumen, at a time associated with an
acquisition of a third endoluminal data point by the endoluminal
data-acquisition device,
[0108] the location-determination functionality is further
configured to determine that third endoluminal data point
corresponds to a location in a vicinity of the second end of the
luminal segment of interest, by determining a location of the
radiopaque marker within the third angiographic image of the lumen
by performing image processing on the third angiographic image, the
location of the radiopaque marker within the third angiographic
image of the lumen corresponding to the third endoluminal data
point;
[0109] the image-co-registration functionality is further
configured to generate a representation of the third marker
location on the combined angiographic image, by co-registering the
first, second, and third angiographic images; and
[0110] the location-association functionality is further configured
to determine that at least one location on the combined
angiographic image that is intermediate to the second and third
locations of the radiopaque marker corresponds to an endoluminal
data point acquired between the acquisitions of the second and
third data points, by interpolating between the second and third
locations of the radiopaque marker on the combined angiographic
image; and
[0111] the display-driving functionality is further configured to
drive the display to display an output, in response to determining
that the intermediate location corresponds to the endoluminal data
point acquired between the acquisitions of the second and third
data points.
[0112] For some applications, the location-association
functionality is configured to interpolate between the first and
second locations of the radiopaque marker on the combined
angiographic image by assuming that, between acquiring respective
successive pairs of endoluminal data points between the
acquisitions of the first and second data points, the endoluminal
data acquisition device traveled equal distances.
[0113] For some applications, the location-association
functionality is configured to interpolate between the first and
second locations of the radiopaque marker on the combined
angiographic image by assuming that a rate of the movement of the
endoluminal data acquisition device was linear between the
acquisitions of the first and second data points.
[0114] There is additionally provided, in accordance with some
applications of the present invention, a method for use with an
endoluminal data-acquisition device configured to be moved through
a lumen of a subject's body, the endoluminal data-acquisition
device having a radiopaque marker coupled thereto, including:
[0115] while the endoluminal data-acquisition device is being moved
through the lumen: [0116] acquiring a plurality of endoluminal data
points of the lumen using the endoluminal data-acquisition device;
[0117] continuously injecting contrast agent into the lumen; and
[0118] acquiring a plurality of angiographic images of the
data-acquisition device;
[0119] determining that endoluminal data points correspond to
respective locations within the lumen, by determining locations of
the radiopaque marker within the angiographic images of the lumen,
by performing image processing on the angiographic images, the
locations of the radiopaque marker within the angiographic images
of the lumen corresponding to respective endoluminal data points;
and
[0120] generating an output in response thereto.
[0121] For some applications, continuously injecting the contrast
agent into the lumen includes continuously injecting the contrast
agent into the lumen for a period of at least two seconds.
[0122] For some applications, acquiring the plurality of
endoluminal data points of the lumen using the endoluminal
data-acquisition device includes acquiring the plurality of
endoluminal data points of the lumen using the endoluminal
data-acquisition device while the data-acquisition device is being
pulled back through the lumen.
[0123] For some applications, continuously injecting the contrast
agent into the lumen includes continuously injecting the contrast
agent over at least 50% of a duration of a period over which the
endoluminal data-acquisition device acquires the endoluminal data
points.
[0124] For some applications, continuously injecting the contrast
agent into the lumen includes continuously injecting the contrast
agent over at least 80% of a duration of a period over which the
endoluminal data-acquisition device acquires the endoluminal data
points.
[0125] There is further provided, in accordance with some
applications of the present invention, apparatus for use with:
[0126] an endoluminal data-acquisition device configured to acquire
a plurality of endoluminal data points of a lumen of a body of a
subject at respective locations inside the lumen, while the
endoluminal data-acquisition device is being moved through the
lumen, the endoluminal data-acquisition device having a radiopaque
marker coupled thereto,
[0127] contrast agent configured to be continuously injected into
the lumen, during the movement of the endoluminal data-acquisition
device,
[0128] an angiographic imaging device configured to acquire a
plurality of angiographic images of the endoluminal
data-acquisition device inside the lumen, during the movement of
the endoluminal data-acquisition device, and
[0129] a display configured to display images of the lumen,
[0130] the apparatus including:
[0131] at least one processor, including: [0132]
location-association functionality configured to determine that
endoluminal data points correspond to respective locations within
the lumen, by determining locations of the radiopaque marker within
the angiographic images of the lumen, by performing image
processing on the angiographic images, the locations of the
radiopaque marker within the angiographic images of the lumen
corresponding to respective endoluminal data points; [0133]
display-driving functionality configured to drive the display to
display an output, in response to determining that the endoluminal
data points correspond to respective locations within the
lumen.
[0134] For some applications, the endoluminal data-acquisition
device includes an endoluminal imaging probe configured to acquire
a plurality of endoluminal images at a first frame rate, the
angiographic imaging device includes an angiographic imaging device
that is configured to acquire the plurality of angiographic images
at a second frame rate that is different from the first frame rate,
and the location-association functionality is configured to
determine that endoluminal data points correspond to respective
locations within the lumen by indexing the endoluminal images with
respect to the angiographic images.
[0135] There is additionally provided, in accordance with some
applications of the present invention, a method for use with an
endoluminal data-acquisition device configured to be moved through
a lumen of a subject's body, the endoluminal data-acquisition
device having a radiopaque marker coupled thereto, including:
[0136] while the endoluminal data-acquisition device is being moved
through the lumen, acquiring a plurality of endoluminal data points
of the lumen using the endoluminal data-acquisition device;
[0137] determining that respective endoluminal data points
correspond to respective locations within the lumen, by acquiring
at least first and second angiographic images of the lumen, and
determining first and second locations of the marker respectively
within the first and second angiographic images;
[0138] generating a combined angiographic image of the lumen that
includes representations thereon of the first and second marker
locations within the lumen, by co-registering the first and second
angiographic images to one another, by: [0139] designating one of
the angiographic images as a baseline image, a shape of the lumen
in the baseline image being designated as a baseline shape of the
lumen; [0140] determining whether a shape of the lumen in the
angiographic image that is not the baseline image is the same as
the baseline shape of the lumen; and [0141] in response to
determining that the shape of the lumen in the angiographic image
that is not the baseline image is not the same as the baseline
shape of the lumen: [0142] designating the image that is not the
baseline image as a non-baseline image, and [0143] deforming the
shape of the lumen in the non-baseline image, such that the shape
of the lumen becomes more similar to the baseline shape of the
portion than when the lumen in the non-baseline image is not
deformed; [0144] based upon the deformation of the non-baseline
image, determining a location upon the baseline image at which the
marker from within the non-baseline image should be located; and
[0145] generating an indication of the marker from within the
non-baseline image at the determined location on the baseline
image.
[0146] For some applications, acquiring the plurality of
endoluminal data points of the lumen using the endoluminal
data-acquisition device while the endoluminal data-acquisition
device is being moved through the lumen includes acquiring the
plurality of endoluminal data points of the lumen using the
endoluminal data-acquisition device while the endoluminal
data-acquisition device is being pulled-back through the lumen.
[0147] There is additionally provided, in accordance with some
applications of the present invention, apparatus for use with:
[0148] an endoluminal data-acquisition device configured to acquire
a plurality of endoluminal data points of a lumen of a body of a
subject at respective locations inside the lumen, while the
endoluminal data-acquisition device is moved through the lumen, the
endoluminal data-acquisition device having a radiopaque marker
coupled thereto,
[0149] an angiographic imaging device configured to acquire
respective angiographic image of the lumen, at times associated
with acquisitions of respective endoluminal data point by the
endoluminal data-acquisition device, and
[0150] a display,
[0151] the apparatus including:
[0152] at least one processor, including: [0153]
location-determination functionality configured to determine first
and second locations of the radiopaque marker respectively within
first and second angiographic images of the lumen; [0154]
image-co-registration functionality configured to generate a
combined angiographic image of the lumen that includes
representations of the first and second marker locations thereon,
by co-registering the first and second angiographic images to one
another, by: [0155] designating one of the angiographic images as a
baseline image, a shape of the lumen in the baseline image being
designated as a baseline shape of the lumen; [0156] determining
whether a shape of the lumen in the angiographic image that is not
the baseline image is the same as the baseline shape of the lumen;
and [0157] in response to determining that the shape of the lumen
in the angiographic image that is not the baseline image is not the
same as the baseline shape of the lumen: [0158] designating the
image that is not the baseline image as a non-baseline image, and
[0159] deforming the shape of the lumen in the non-baseline image,
such that the shape of the lumen becomes more similar to the
baseline shape of the portion than when the lumen in the
non-baseline image is not deformed; [0160] based upon the
deformation of the non-baseline image, determining a location upon
the baseline image at which the marker from within the non-baseline
image should be located; and [0161] generating an indication of the
marker from within the non-baseline image at the determined
location on the baseline image; and [0162] display-driving
functionality configured to drive the display to display an output,
in response to generating the combined angiographic image of the
lumen.
[0163] For some applications, the location-determination
functionality is configured to:
[0164] determine that a first endoluminal data point corresponds to
a first location within the lumen, by determining a location of the
radiopaque marker within the first angiographic image of the lumen,
by performing image processing on the angiographic image, the
location of the first radiopaque marker within the first
angiographic image of the lumen corresponding to the first
endoluminal data point, and
[0165] determine that a second endoluminal data point corresponds
to a second given location within the lumen by determining a
location of the radiopaque marker within the second angiographic
image of the lumen by performing image processing on the second
angiographic image, the location of the radiopaque marker within
the second angiographic image of the lumen corresponding to the
second endoluminal data point.
[0166] For some applications, the location-determination
functionality is configured to:
[0167] determine that the first endoluminal data point corresponds
to the first location within the lumen by determining that the
first endoluminal data point corresponds to a location in a
vicinity of a first end of a luminal segment of interest, and
[0168] determine that the second endoluminal data point corresponds
to the second location within the lumen by determining that the
second endoluminal data point corresponds to a location in a
vicinity of a second end of the luminal segment of interest.
[0169] For some applications, the at least one processor further
includes location-association functionality configured to determine
that at least one location on the combined angiographic image that
is intermediate to the first and second locations of the radiopaque
marker corresponds to an endoluminal data point acquired between
the acquisitions of the first and second data points, by
interpolating between the first and second locations of the
radiopaque marker on the combined angiographic image.
[0170] There is further provided, in accordance with some
applications of the present invention, a method for imaging a tool
inside a portion of a body of a subject that undergoes motion, the
tool having contours, the method including:
[0171] acquiring a plurality of image frames of the portion of the
subject's body; and
[0172] generating at least one image frame in which the tool is
enhanced, by: [0173] identifying radiopaque markers in the image
frames; [0174] identifying edge lines in a vicinity of the markers
within the image frames, the edge lines corresponding to contours
of the tool; [0175] in response to the identifying of the edge
lines, selecting a subset of the image frames that are based upon
the acquired image frames, based upon a level of similarity between
the edge lines in the selected image frames to one another; [0176]
aligning the contours in a plurality of the selected image frames,
and [0177] averaging the plurality of aligned frames to generate an
averaged image frame; and
[0178] displaying the averaged image frame.
[0179] There is further provided, in accordance with some
applications of the present invention, apparatus for use with a
tool configured to be placed inside a portion of a body of a
subject that undergoes motion, the tool having contours, an
image-acquisition device configured to acquire a plurality of image
frames of the portion of the subject's body, and a display, the
apparatus including:
[0180] at least one processor configured to generate at least one
image frame in which the tool is enhanced, the processor including:
[0181] image-receiving functionality configured to receive the
plurality of image frames into the processor, [0182]
marker-identifying functionality configured to automatically
identify radiopaque markers in the image frames, [0183]
edge-line-identifying functionality configured to automatically
identify edge lines in a vicinity of the radiopaque markers in the
image frames, [0184] image-selection functionality configured, in
response to the identifying of the edge lines, to select a subset
of the image frames that are based upon the acquired image frames,
based upon a level of similarity between the edge lines in the
selected image frames to one another, [0185] image-alignment
functionality configured to align the edge lines in a plurality of
the selected image frames, and [0186] image-averaging functionality
configured to generate an averaged image frame by averaging the
plurality of aligned image frames; and [0187] display-driving
functionality configured to drive the display to display the
averaged image frame.
[0188] For some applications, the image-selection functionality is
configured to select the subset of image frames based upon a level
of similarity between shapes of the edge lines in the image
frames.
[0189] For some applications, the image-selection functionality is
configured to select the subset of image frames based upon a level
of alignment between the edge lines and the radiopaque markers in
the image frames.
[0190] For some applications, the image-selection functionality is
configured to select the subset of image frames by rejecting from
being included in the subset, at least one image frame in which
edge lines corresponding to the contours of the tool appear.
[0191] For some applications, the image-alignment functionality is
configured to align the edge lines in the selected image frames by
translating at least one image frame with respect to at least one
other image frame of the selected image frames.
[0192] For some applications, the processor is configured to
generate a plurality of image frames in which the tool is enhanced,
and the display-driving functionality is configured to drive the
display to display, as an image stream, the plurality of image
frames in which the tool is enhanced.
[0193] For some applications, the tool includes a stent that is
inserted into the lumen while disposed on a device, and the
marker-identifying functionality is configured to identify the
radiopaque markers by identifying radiopaque markers that are
coupled to the device, and the edge-line-identifying functionality
is configured to identify the edge lines by identifying curved edge
lines, corresponding to contours of the stent.
[0194] For some applications, the image-selection functionality is
configured to select the subset of image frames based upon a level
of similarity between shapes of the curved edge lines in the image
frames.
[0195] For some applications, the marker-identifying functionality
is configured to identify first and second radiopaque markers that
are coupled to the device, and the image-selection functionality is
configured to select the subset of image frames based upon a level
of alignment between the edge lines and an imaginary line running
from the first marker to the second marker in the image frames.
[0196] There is further provided, in accordance with some
applications of the present invention, a method for use with an
endoluminal data-acquisition device configured to acquire
endoluminal data points while moving through a lumen of a subject's
body generally in a first direction with respect to the lumen,
including:
[0197] while the endoluminal data-acquisition device is being moved
through the lumen, acquiring a plurality of endoluminal data points
of the lumen using the endoluminal data-acquisition device;
[0198] determining that, at at least one location, two or more
endoluminal data points were acquired;
[0199] generating an output using a portion of the plurality of
endoluminal data points of the lumen acquired using the endoluminal
data-acquisition device, by using only a single endoluminal data
point corresponding to the location.
[0200] There is further provided, in accordance with some
applications of the present invention, apparatus for use with an
endoluminal data-acquisition device that acquires a plurality of
endoluminal data points of a lumen of a body of a subject while
being moved through the lumen generally in a first direction with
respect to the lumen, and a display, the apparatus including:
[0201] at least one processor including: [0202]
duplicate-data-point-identification functionality configured to
determine that, at at least one location, two or more endoluminal
data points were acquired by the endoluminal data-acquisition
device; [0203] data-point-selection functionality configured to
generate an output using a portion of the plurality of endoluminal
data points of the lumen acquired using the endoluminal
data-acquisition device, by using only a single data point
corresponding to the location; and [0204] display-driving
functionality configured to drive the display to display the
output.
[0205] For some applications, the data-point-selection
functionality is configured to use only the single data point
corresponding to the location by using a single one of the two or
more endoluminal data points that were acquired at the at least one
location, and rejecting another one of the two or more endoluminal
data points from being used in the output
[0206] For some applications, the data-point-selection
functionality is configured to generate the output selecting for
use as the single data point a data point that was acquired at the
given location at an earliest time with respect to the data points
that were acquired at the given location.
[0207] For some applications, the data-point-selection
functionality is configured to generate the output by rejecting
from being used in the output an endoluminal data point that was
acquired while the device was moving in a second direction with
respect to the lumen that is opposite to the first direction.
[0208] For some applications, the data-point-selection
functionality is configured:
[0209] to generate the output by generating an indication that one
of the two or more endoluminal data points is associated with the
location by co-registering the portion of the plurality of
endoluminal data points of the lumen with the extraluminal image,
and
[0210] to reject the other one of the two or more endoluminal data
points from being used in the output by rejecting one of the two or
more endoluminal images from being indicated to be associated with
the location.
[0211] For some applications,
[0212] the endoluminal data-acquisition device includes an
endoluminal imaging probe configured to acquire a plurality of
endoluminal image frames of the lumen, and
[0213] the data-point-selection functionality is configured: [0214]
to generate the output by generating an endoluminal image stack
using some of the plurality of endoluminal image frames of the
lumen, and [0215] to reject the other one of the two or more
endoluminal data points from being used in the output by rejecting
the other one of the two or more endoluminal image frames from
being displayed in the image stack.
[0216] For some applications, the
duplicate-data-point-identification functionality is configured to
determine that, at at least one location, two or more endoluminal
data points were acquired by determining that the endoluminal
data-acquisition device moved past the location in a second
direction with respect to the lumen that is opposite to the first
direction, and the data-point-selection functionality is configured
to generate the output by placing image frames in order within the
image stack based on determining that the endoluminal
data-acquisition device moved past the location, in the second
direction with respect to the lumen.
[0217] For some applications, the
duplicate-data-point-identification functionality is configured to
determine that, at at least one location, two or more endoluminal
data points were acquired by:
[0218] sensing a signal that is indicative of the subject's cardiac
cycle, while the endoluminal data-acquisition device acquires the
plurality of data points,
[0219] determining that a given data point was acquired at a given
phase of the subject's cardiac cycle, and
[0220] in response thereto, identifying the given data point as
having been acquired at a location at which another data point was
acquired.
[0221] For some applications, the
duplicate-data-point-identification functionality configured to
determine that the given data point was acquired at the given phase
of the subject's cardiac cycle by determining that the given data
point was acquired during at least a portion of systole.
[0222] For some applications, the
duplicate-data-point-identification functionality is configured to
determine that, at at least one location, two or more endoluminal
data points were acquired by determining that the endoluminal
data-acquisition device moved past the location in a second
direction with respect to the lumen that is opposite to the first
direction.
[0223] For some applications, the
duplicate-data-point-identification functionality configured to
determine that the endoluminal data-acquisition device moved past
the location in the second direction with respect to the lumen by
performing image processing on extraluminal images of the device
moving through the lumen generally in the first direction.
[0224] For some applications, the apparatus further includes a
sensor configured to detect movement of a portion of the
endoluminal data-acquisition device, and the
duplicate-data-point-identification functionality is configured to
determine that the endoluminal data-acquisition device moved past
the location in the second direction with respect to the lumen, in
response to a signal from the sensor.
[0225] There is further provided, in accordance with some
applications of the present invention, a method for use with an
endoluminal data-acquisition device configured to acquire
endoluminal data points while moving through a lumen of a subject's
body generally in a first direction with respect to the lumen,
including:
[0226] while the endoluminal data-acquisition device is being moved
through the lumen, acquiring a plurality of endoluminal data points
of the lumen using the endoluminal data-acquisition device;
[0227] determining that, while acquiring at least one of the
endoluminal data points, the endoluminal data-acquisition device
was moving in a second direction that is opposite to the first
direction; and
[0228] in response to the determining, generating an output using
at least some of the plurality of endoluminal data points of the
lumen acquired using the endoluminal data-acquisition device.
[0229] There is additionally provided, in accordance with some
applications of the present invention, apparatus for use with an
endoluminal data-acquisition device that acquires a plurality of
endoluminal data points of a lumen of a body of a subject while
being moved through the lumen generally in a first direction with
respect to the lumen and a display, the apparatus including:
[0230] at least one processor including: [0231]
direction-determination functionality configured to determine that,
while acquiring at least one of the endoluminal data points, the
endoluminal data-acquisition device was moving in a second
direction that is opposite to the first direction; [0232]
output-generation functionality configured, in response to the
determining, to generate an output using at least some of the
plurality of endoluminal data points of the lumen acquired using
the endoluminal data-acquisition device; and [0233] display-driving
functionality configured to drive the display to display the
output.
[0234] For some applications, the direction-determination
functionality is configured to determine that, while acquiring at
least one of the endoluminal data points, the endoluminal
data-acquisition device was moving in a second direction that is
opposite to the first direction by performing image processing on
extraluminal images of the device moving through the lumen
generally in the first direction.
[0235] For some applications, the apparatus further includes a
sensor configured to detect movement of a portion of the
endoluminal data-acquisition device, and the
direction-determination functionality configured to determine that,
while acquiring at least one of the endoluminal data points, the
endoluminal data-acquisition device was moving in a second
direction that is opposite to the first direction, in response to a
signal from the sensor.
[0236] For some applications,
[0237] the endoluminal data-acquisition device includes an
endoluminal imaging probe configured to acquire a plurality of
endoluminal image frames of the lumen, and
[0238] the output-generation functionality is configured to
generate the output by generating an endoluminal image stack using
at least some of the plurality of endoluminal image frames of the
lumen.
[0239] For some applications, the output-generation functionality
is configured to generate the output by placing image frames in
order within the image stack based on determining that, while
acquiring at least one of the endoluminal data points, the
endoluminal data-acquisition device was moving in the second
direction.
[0240] For some applications, the output-generation functionality
is configured to generate the output by generating an indication on
the endoluminal image stack of at least a portion of the
endoluminal image stack that was acquired by the data-acquisition
device while the data-acquisition device was moving in the second
direction.
[0241] For some applications, the direction-determination
functionality is configured to determine that, while acquiring at
least one of the endoluminal data points, the endoluminal
data-acquisition device was moving in a second direction that is
opposite to the first direction by:
[0242] sensing a signal that is indicative of the subject's cardiac
cycle, while the endoluminal data-acquisition device acquires the
plurality of data points,
[0243] determining that a given data point was acquired at a given
phase of the subject's cardiac cycle, and
[0244] in response thereto, identifying the given data point as
having been acquired while the endoluminal data-acquisition device
was moving in the second direction.
[0245] For some applications, the direction-determination
functionality is configured to determine that the given data point
was acquired at the given phase of the subject's cardiac cycle by
determining that the given data point was acquired during at least
a portion of systole.
[0246] The present invention will be more fully understood from the
following detailed description of embodiments thereof, taken
together with the drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0247] FIG. 1 is a flow chart, at least some of the steps of which
are used in procedures that utilize co-use of endoluminal data and
extraluminal imaging, in accordance with some applications of the
present invention;
[0248] FIGS. 2A-B are schematic illustrations of an endoluminal
device being inserted into a lumen, and (in FIG. 2B) a sensor for
sensing the distance traveled through the lumen by the endoluminal
device relative to a known starting location, in accordance with
some applications of the present invention;
[0249] FIG. 3 is a flow chart, at least some of the steps of which
are used in procedures that utilize co-use of endoluminal data and
extraluminal imaging, in accordance with some applications of the
present invention;
[0250] FIG. 4 shows an initial best angiogram of a luminal segment,
the initial best angiogram being generated prior to the
commencement of the pullback of an endoluminal imaging probe, in
accordance with some applications of the present invention;
[0251] FIG. 5 shows a post-pullback best angiogram of a luminal
segment, the post-pullback best angiogram being generated
subsequent to the termination of the pullback of an endoluminal
imaging probe, in accordance with some applications of the present
invention;
[0252] FIG. 6 shows a combined best angiogram of a luminal segment,
the combined best angiogram being generated by co-registering the
initial best angiogram and the post-pullback best angiogram, in
accordance with some applications of the present invention;
[0253] FIG. 7 shows the co-use of previously-acquired endoluminal
images and an extraluminal fluoroscopic image, in accordance with
some applications of the present invention;
[0254] FIG. 8 shows a location on an extraluminal image of a lumen
that has been selected, the index of the corresponding endoluminal
image frame being derived in response thereto, in accordance with
some applications of the present invention;
[0255] FIG. 9 shows co-display of previously-acquired endoluminal
images and an extraluminal fluoroscopic image, in accordance with
some applications of the present invention;
[0256] FIG. 10 shows the co-use of previously-acquired endoluminal
images and a current extraluminal fluoroscopic image stream, in
accordance with some applications of the present invention;
[0257] FIG. 11 shows the co-use of a stack of previously-acquired
IVUS images and a current, extraluminal fluoroscopic image stream,
in accordance with some applications of the present invention;
[0258] FIG. 12 is a graph indicating typical movement of an
endoluminal imaging probe during pullback of the probe; and
[0259] FIG. 13 shows an extraluminal image of a stent inside a
blood vessel that has been enhanced, in accordance with some
applications of the present invention.
DETAILED DESCRIPTION OF EMBODIMENTS
[0260] The terms "medical tool," "tool", "device," and "probe"
refer to any type of a diagnostic or therapeutic or other
functional tool including, but not limited to, a cardiovascular
catheter, a stent delivery and/or placement and/or retrieval tool,
a balloon delivery and/or placement and/or retrieval tool, a valve
delivery and/or repair and/or placement and/or retrieval tool, a
graft delivery and/or placement and/or retrieval tool, a tool for
the delivery and/or placement and/or retrieval of an implantable
device or of parts of such device, an implantable device or parts
thereof, a tool for closing a gap, a tool for closing a septal
defect, a guide wire, a marker wire, a suturing tool, a clipping
tool (such as a valve-leaflet-clipping tool), a biopsy tool, an
aspiration tool, a navigational tool, a localization tool, a probe
comprising one or more location sensors, a tissue characterization
probe, a probe for the analysis of fluid, a measurement probe, an
electrophysiological probe, a stimulation probe, an ablation tool,
a tool for penetrating or opening partial or total occlusions in
blood vessels, a drug or substance delivery tool, a chemotherapy
tool, a photodynamic therapy tool, a brachytherapy tool, a local
irradiation tool, a laser device, a tool for delivering energy, a
tool for delivering markers or biomarkers, a tool for delivering
biological glue, an irrigation device, a suction device, a
ventilation device, a device for delivering and/or placing and/or
retrieving a lead of an electrophysiological device, a lead of an
electrophysiological device, a pacing device, a coronary sinus
device, an imaging device, a sensing probe, a probe comprising an
optical fiber, a robotic tool, a tool that is controlled remotely,
an excision tool, a plaque excision tool (such as a plaque excision
catheter) or any combination thereof [0261] The terms "image" and
"imaging" refer to any type of medical imaging, typically presented
as a sequence of images and including, but not limited to, imaging
using ionizing radiation, imaging using non-ionizing radiation,
video, fluoroscopy, angiography, ultrasound, CT, MR, PET, PET-CT,
CT angiography, SPECT, Gamma camera imaging, Optical Coherence
Tomography (OCT), Near-Infra-Red Spectroscopy (NIRS), Vibration
[0262] Response Imaging (VRI), Optical Imaging, infrared imaging,
electrical mapping imaging, other forms of Functional Imaging, or
any combination or fusion thereof. Examples of ultrasound imaging
include Endo-Bronchial Ultrasound (EBUS), Trans-Thoracic Echo
(TTE), Trans-Esophageal Echo (TEE), Intra-Vascular Ultrasound
(IVUS), Intra-Cardiac Ultrasound (ICE), or any combination thereof
[0263] The term "contrast agent," when used in reference to its
application in conjunction with imaging, refers to any substance
that is used to highlight, and/or enhance in another manner, the
anatomical structure, functioning, and/or composition of a bodily
organ while the organ is being imaged. [0264] The term
"stabilized," when used in the context of displayed images, means a
display of a series of images in a manner such that periodic,
cyclical, and/or other motion of the body organ(s) being imaged,
and/or of a medical tool being observed, is partially or fully
reduced, with respect to the entire image frame, or at least a
portion thereof [0265] The term "automatic," when used for
describing the generation and utilization of the road map, means
"without necessitating user intervention or interaction." (Such
interaction or intervention may still however be optional in some
cases.) [0266] The term "real time" means without a noticeable
delay. [0267] The term "near real time" means with a short
noticeable delay (such as approximately one or two motion cycles of
the applicable organ, and, in the case of procedures relating to
organs or vessels the motion of which are primarily as a result of
the cardiac cycle, less than two seconds). [0268] The term
"on-line," when used in reference to image processing, or to
measurements being made on images, means that the image processing
is performed, and/or the measurements are made, intra-procedurally,
in real time or near real time.
[0269] Applications of the present invention are typically used
during medical procedures that are performed, in whole or in part,
on or within luminal structures. For some applications, apparatus
and methods provided herein facilitate the co-use of extraluminal
imaging and endoluminal data in performing such medical procedures.
Endoluminal data may include imaging data, data derived from
measurements, other data, or any combination thereof.
[0270] For some applications, the co-use of the endoluminal data
and the extraluminal images is performed in the following manner.
Endoluminal data are acquired by positioning an endoluminal
data-acquisition device along a luminal segment of interest that
includes a designated luminal site. Subsequently, while observing
extraluminal images of the luminal segment, one or more locations
along that segment are indicated by a user input device. In
response to the indication of the one or more locations by the user
input device, the corresponding, previously-acquired endoluminal
images are displayed.
[0271] Typically, the designated luminal site includes a site being
diagnosed, and at which, subject to the outcome of the diagnosis, a
therapeutic device will be positioned and deployed, e.g., the site
of an anatomical feature, the implantation site of a
previously-implanted device, and/or a site at a defined location
with respect to the implantation site. For example, the designated
luminal site may include a portion of the lumen that is narrow with
respect to surrounding portions of the lumen, and/or the site of a
lesion.
[0272] For some applications, the co-use of the endoluminal data
and the extraluminal images is performed in the following manner.
Endoluminal data are acquired by positioning an endoluminal
data-acquisition device at a designated luminal site. Subsequently,
an endoluminal therapeutic device is positioned and deployed at the
designated luminal site under extraluminal imaging, while
concurrently viewing on-line the endoluminal data that were
previously acquired by the endoluminal data-acquisition device at
the current location of the therapeutic device. Typically,
endoluminal data are acquired at respective endoluminal sites in
the vicinity of the designated endoluminal site. Subsequently, when
the endoluminal therapeutic device is placed inside the lumen,
previously-acquired endoluminal data are displayed and updated,
typically automatically and typically on-line, to correspond to the
current location of the therapeutic device (or of a portion
thereof), the location of the therapeutic device typically changing
during the positioning of the therapeutic device.
[0273] For some applications, extraluminal imaging and the
previously-acquired endoluminal data are co-used such that it is as
if the therapeutic device is being positioned and deployed under
both real-time extraluminal imaging and real-time endoluminal data
acquisition. This is because (a) the extraluminal imaging is
performed in real-time, and (b), although the endoluminal data are
not acquired in real-time, endoluminal data are displayed that
correspond to the current location of the therapeutic device.
[0274] In accordance with some applications of the present
invention, when the therapeutic device is disposed inside the
lumen, the location of the device within the lumen is determined by
performing image processing on the extraluminal image of the device
inside the lumen.
[0275] For some applications, the image processing includes
tracking of one or more visible portions of a moving
therapy-applying portion of the device in the extraluminal images.
Typically, the tracking is performed in real time, and, typically,
in accordance with techniques described in US 2010/0228076 to
Blank, which is incorporated herein by reference.
[0276] For some applications, the image processing includes
stabilization of an image stream produced by the extraluminal
imaging. Typically, the stabilization is performed in real time,
and typically in accordance with techniques described in US
2008/0221442 to Tolkowsky, or US 2010/0228076 to Blank, both of
which applications are incorporated herein by reference. Typically,
the stabilization facilitates the co-use of the endoluminal data
with the extraluminal images (particularly in cases of intense
organ motion). This is because it is typically easier to determine
the luminal location of the therapeutic device based upon a
stabilized image stream than to determine the luminal location of
the therapeutic device on a native, non-stabilized image
stream.
[0277] For some applications, the stabilized image stream is also
enhanced, typically in real time, typically in accordance with
techniques described in US 2010/0228076 to Blank.
[0278] For some applications, during the acquisition of the
endoluminal data by the endoluminal data-acquisition device, the
location of the endoluminal data-acquisition device is determined
by advancing the endoluminal data-acquisition device under
extraluminal imaging and image processing the extraluminal images
to determine the location of a moving data-acquiring portion of the
endoluminal data-acquisition device. For some applications, during
this stage, the extraluminal image stream is stabilized and/or
enhanced, as described hereinabove, to facilitate the determination
of the location of the endoluminal data-acquisition device, based
upon the extraluminal images. Alternatively, other techniques are
used for determining the location of the endoluminal
data-acquisition device, as described hereinbelow.
[0279] For some applications, the luminal structure to which the
apparatus and methods described herein are applied includes a lumen
in the vascular system, the respiratory tract, the digestive tract,
the urinary tract, or any other luminal structure within a
patient's body.
[0280] For some applications, the endoluminal data-acquisition
device is an imaging probe. For some applications, the imaging
probe is an IVUS probe, an EBUS probe, another ultrasound probe, an
OCT probe, an NIRS probe, an MR probe, or any combination
thereof.
[0281] For some applications, the endoluminal data-acquisition
device performs additional functions. For example, the endoluminal
data-acquisition device may comprise a probe, such as the VIBE.TM.
RX Vascular Imaging Balloon Catheter, marketed by Volcano
Corporation (San Diego, USA), that includes both IVUS and coronary
balloon functionalities.
[0282] For some applications, the endoluminal data-acquisition
device acquires data in a form other than images. For example, the
data may include data related to pressure, flow, temperature,
electrical activity, or any combination thereof. For some
applications, and typically when data are acquired with respect to
a coronary vessel, the endoluminal data-acquisition device is a
Fractional Flow Reserve (FFR) probe.
[0283] For some applications, the extraluminal imaging is
fluoroscopy, CT, MR, PET, SPECT, ultrasound, or any combination
thereof.
[0284] For some applications, the apparatus and methods described
herein are used with a therapeutic device that is positioned and/or
deployed at an anatomical feature that requires or potentially
requires treatment, such as a partial or total occlusion, a native
valve, an aneurism, a dissection, a malformation, a septal defect,
a mass suspected of being malignant, a mass suspected of being
inflammatory, etc. The endoluminal data are typically determined
at, and/or in the vicinity of, the anatomical feature.
[0285] For some applications, apparatus and methods described
herein are used with a therapeutic device that is positioned and/or
deployed at an implantation site of a previously-implanted device
such as a stent, a graft or a replacement valve. The endoluminal
data are determined at, and/or in the vicinity of, the implantation
site. For example, the techniques described herein may be used
during the placement of a new prosthetic aortic valve at the site
of (e.g., inside) a previously implanted prosthetic aortic valve
that is no longer functioning.
[0286] For some applications, apparatus and methods described
herein are used with a therapeutic device that is positioned and/or
deployed at a defined location relative to a previously-implanted
device such as a stent, a graft or a replacement valve. The
endoluminal data are determined at and in the vicinity of the
defined location. For example, the techniques described herein may
be used during the placement of a coronary stent such that the new
stent overlaps with or is adjacent to a previously-implanted stent,
in order to treat a long lesion and/or a lesion that has diffused
along a coronary artery.
[0287] Reference is now made to FIG. 1, which is a flow chart, at
least some of the steps of which are used in the course of co-use
of endoluminal data and extraluminal imaging, in accordance with
some applications of the current invention. It is noted that, for
some applications, some of the steps shown in FIG. 1 may be
practiced, without all of the steps shown in FIG. 1 necessarily
being practiced in combination.
[0288] In phase 1, extraluminal imaging is activated. Typically the
extraluminal imaging is activated at this stage, in order to
facilitate determination of the location of a moving data-acquiring
portion the endoluminal data-acquisition device by performing image
processing on the extraluminal images, and/or in order to
facilitate the insertion of the endoluminal data-acquisition
device. For some applications, methods other than extraluminal
imaging are used for determining the location of the endoluminal
data-acquisition device, for example, as described hereinbelow. For
some applications (e.g., during insertion of the data-acquisition
device into an endobronchial lumen, which may be performed without
the guidance of extraluminal imaging), the extraluminal imaging is
not activated at this stage.
[0289] In phase 2, the extraluminal image stream is typically
stabilized, and optionally enhanced, typically in accordance with
techniques previously disclosed in US 2008/0221442 to Tolkowsky,
and/or US 2010/0228076 to Blank, both of which applications are
incorporated herein by reference. For some applications, the
extraluminal image stream is stabilized with respect to radiopaque
markers on the endoluminal data-acquisition device.
[0290] In phase 3, the endoluminal data-acquisition device is
inserted towards the designated site. The designated site is
typically a site being diagnosed, and at which, subject to the
outcome of such diagnosis, the therapeutic device will be
positioned and deployed, e.g., the site of an anatomical feature,
the implantation site of a previously-implanted device, and/or a
site at a defined location with respect to the implantation site,
as described hereinabove. The endoluminal data-acquisition device
is typically imaged by extraluminal imaging.
[0291] In phase 4, endoluminal data, typically images, are acquired
by the endoluminal data-acquisition device. Typically, data are
acquired at and/or in the vicinity of the designated site.
Typically, a plurality of data points (e.g., images) are acquired
at respective locations along the lumen. It is noted that, for some
applications, data are acquired subsequent to the initial insertion
of the data-acquisition device into the lumen. For example, when
data are acquired from blood vessels, the data-acquisition device
is typically inserted into the blood vessel to beyond the site of
interest under extraluminal imaging (e.g., fluoroscopy). Data
acquisition is typically performed during (manual or automated)
pullback of the data-acquisition device through the blood vessel.
In alternative applications, e.g., when data are acquired from an
endobronchial airway, data are typically acquired by the
data-acquisition device during insertion of the data-acquisition
device into the airway.
[0292] For some applications, in the course of pullback of the
data-acquisition device, the lumen (for example, a coronary artery)
also experiences a cyclical motion (for example, due to the cardiac
cycle) that causes it to pulsate and move back and forth relatively
to the endoluminal data-acquisition device. For some applications,
e.g., in the case of a lumen that undergoes such back-and-forth
cyclical motion, data acquired by the endoluminal data-acquisition
device are gated to the cyclical motion cycle of the lumen.
Subsequently, endoluminal data acquired in the course of the
pullback at at-least-one specific phase of the motion cycle of the
lumen are co-registered with one or more extraluminal images
acquired, and gated, at the corresponding at-least-one phase during
the pullback, in order to facilitate co-registration of the
endoluminal data with the extraluminal images, in accordance with
the techniques described herein. For some applications,
co-registering endoluminal data with extraluminal images that are
gated to the same phase as the phase to which the endoluminal data
were gated, reduces distortions in the co-registration that may be
introduced due to the cyclical motion of the lumen in the absence
of using the aformentioned gating techniques.
[0293] For some applications, there is a single, gated extraluminal
angiogram image to which all gated endoluminal data are
co-registered. For some applications, a three-dimensional model is
generated from two (or more) two-dimensional gated angiograms, and
the gated endoluminal data is co-registered with that
three-dimensional model.
[0294] For some applications, the commencement and/or termination
of pullback are identified, typically automatically and typically
on-line, by means of image processing. For some applications, the
image processing is performed by an image comparator which
identifies a change (such as in the color of image pixels or in the
geometry of image features) in the sequentially-acquired
endoluminal images, and interprets the change as indicating the
commencement of pullback. For some applications, the image
processing is performed by an image comparator which identifies a
diminishing change in the sequentially-acquired endoluminal images,
and interprets the diminishing change as indicating the termination
of pullback.
[0295] For some applications, the commencement and/or termination
of pullback are identified by means of a signal transmitted by the
pullback unit and/or by the endoluminal data acquisition system.
For some applications, the commencement and/or termination of
pullback are indicated by means of user input.
[0296] In phase 5, each applicable image or data point acquired in
phase 4 is, typically automatically, assigned a location. The
locations assigned to respective data points (e.g., images)
correspond to the location of the endoluminal data-acquisition
device when the respective data points are acquired. Typically,
this step is performed simultaneously with phase 4, such that the
system assigns locations corresponding to respective data points at
the time of the acquisition of the data points.
[0297] For some applications, the location of a data-acquiring
portion of the endoluminal data-acquisition device that moves
during pullback, and a portion of which is visible in the
extraluminal imaging, is identified via image processing. For
example, radiopaque markers on a moving imaging portion of the
endoluminal data-acquisition device may be identified in
extraluminal fluoroscopic images. For some applications, the
visible portion is identified and tracked, typically on-line and
typically automatically, for example, in accordance with techniques
described in US 2010/0228076 to Blank.
[0298] For some applications, the location of the moving, visible
portion of the endoluminal data-acquisition device is determined
relative to an anatomical feature visible in the extraluminal
imaging. For some applications, the feature is a bifurcation, a
curve or some other unique shape, a partial or total occlusion, a
native valve, an aneurism, a septal defect, or a malformation. For
some applications, contrast agent is injected in order to make the
feature visible (for example, in the case of vasculature that is
imaged under fluoroscopy). Typically, the quantity and
concentration of the contrast agent that is injected is such that,
in some image frames, both the visible portion of the endoluminal
data-acquisition device and the anatomical feature may be discerned
concurrently in the extraluminal image.
[0299] For some applications, the location of the moving, visible
portion of the endoluminal data-acquisition device is determined
relative to a previously-deployed device visible in the
extraluminal imaging. For some applications, the
previously-deployed device is a stent, or a graft, or a replacement
valve.
[0300] For some applications, the location of the moving, visible
portion of the endoluminal data-acquisition device is determined
relative to visible markers along a guide wire along which the
endoluminal data-acquisition device is inserted.
[0301] For some applications, the location of the moving, visible
portion of the endoluminal data-acquisition device is determined
according to its distance along a guide wire along which the
endoluminal data-acquisition device is inserted, the distance
typically being measured relative to the distal tip of a guiding
catheter through which the guide wire was previously inserted (or
relative to any other of the aforementioned visible features). For
some applications, the endoluminal data-acquisition device includes
a portion that substantially does not move with respect to the
lumen during pullback, such as an insertion sheath. The location of
moving, visible portion of the data-acquisition device is
determined, via image processing, with reference to the portion of
the device that substantially does not move with respect to the
lumen during pullback.
[0302] For some applications, the location of the moving visible
portion of the endoluminal data-acquisition device is determined by
means of display coordinates. Typically, for such applications,
when an endoluminal therapeutic device is subsequently inserted
into the lumen in order to treat the designated site, the same
viewing angle of the extraluminal imaging device relative to the
lumen, and the same zoom level of the extraluminal imaging are used
as were used to image the endoluminal data-acquisition device
inside the lumen. For such applications, the position of the
subject typically remains substantially unchanged between the
insertion of the data-acquisition device and the insertion of the
therapeutic device. Thus, the location of the endoluminal
data-acquisition device within the lumen may be matched with the
location of the therapeutic device that is subsequently inserted
into the lumen.
[0303] For some applications, the location of the moving, visible
portion of the endoluminal data-acquisition device is determined by
determining a distance traveled by the device along the lumen, from
a known starting location. For some applications, the distance is
measured by a pullback unit to which the device is connected. For
some applications, the distance is measured by a longitudinal
position/movement sensor coupled to apparatus through which the
endoluminal data-acquisition device is inserted, e.g., as described
hereinbelow with reference to FIG. 2. For some applications, the
apparatus is a guiding catheter. Typically, the sensor measures the
extent of longitudinal movement (e.g., insertion, pullback) of a
proximal portion of the device. For some applications, the sensor
is optical (e.g., laser-based), or mechanical, or electric, or
magnetic, or any combination thereof. For some applications, in
response to measuring the extent of the longitudinal motion of the
proximal portion of the device, the system estimates a distance by
which the moving, data-acquiring portion has moved along the lumen
(typically, along a center line of the lumen), typically
automatically and typically on-line. The center line is determined,
typically automatically, in accordance with techniques described in
US 2010/0228076 to Blank, which is incorporated herein by
reference.
[0304] For some applications, the location of the moving portion of
the endoluminal data-acquisition device is determined according to
techniques described in US Patent Application 2006/0241465 and US
Patent Application 2007/0038061, both to Huennekens, and both of
which applications are incorporated herein by reference. For some
applications, techniques as described in U.S. Pat. No. 5,357,550 to
Asahina, US 2011/0034801 to Baumgart, and/or U.S. Pat. No.
7,729,746 to Redel are applied, in order to determine the location
of the moving portion of the endoluminal data-acquisition device.
All of the aforementioned references are incorporated herein by
reference.
[0305] For some applications, the location of the endoluminal
data-acquisition device is determined even in the absence of
simultaneous extraluminal imaging. For example, it may be
determined that the device is at an anatomical feature such as a
bifurcation, based upon the images or data acquired by the device.
Subsequently, the device may be pulled back at a known speed, by a
pullback unit to which the device is connected. Alternatively, the
distance by which the device has been pulled back at the
acquisition of respective data points may be measured. Thus, it may
be determined, at the time of acquisition of a given image or a
given data point, what is the location of the device relative to
the anatomical feature. Separately (before or after acquisition of
the endoluminal data), the anatomical feature is identified in an
extraluminal image of the lumen. Based upon the location of the
anatomical feature in the extraluminal image, endoluminal data
points (e.g., images) are assigned to respective locations within
the extraluminal image.
[0306] For some applications, other techniques are applied, e.g.,
techniques described hereinbelow with reference to FIG. 3 are
applied, in order to determine the location of the endoluminal
data-acquisition device when the respective data points (e.g.,
images) are acquired.
[0307] In phase 6, the endoluminal data-acquisition device is
typically retrieved from the designated site (and, further
typically, withdrawn from the lumen), in order to accommodate the
insertion of an endoluminal device (e.g., an endoluminal
therapeutic device) into the lumen.
[0308] In phase 7, while observing extraluminal images of the
luminal segment comprising the designated location, one or more
locations along that section are indicated by a user input device.
In response thereto, the previously-acquired endoluminal images
corresponding to the one or more locations are displayed. For some
applications, the user input device is used to select the one or
more locations. Typically, the user designates a location using the
user input device, and, in response thereto, typically
automatically and on-line, the system identifies a location along
the lumen (e.g., along the luminal center line) as corresponding to
the designated location, and retrieves and displays a corresponding
endoluminal image. For some applications, the center line is
generated in accordance with techniques described in US
2010/0220917 to Steinberg, which is incorporated herein by
reference.
[0309] Alternatively or additionally, by observing an angiogram
frame side by side with endoluminal image frames of the luminal
segment comprising the designated location, one or more locations
along the section are indicated by a user input device with respect
to endoluminal imaging data. For some applications, the user
indication is made upon the endoluminal image stack. For some
applications, the user indication is made by browsing through the
endoluminal images. In response to receiving the user indication,
the location along the lumen (e.g., along the luminal center line)
within the angiogram corresponding to the location indicated with
respect to an endoluminal image or the endoluminal image stack is
determined and indicated.
[0310] Typically, a clinical diagnosis is facilitated by an
operator viewing previously-acquired endoluminal images
corresponding to the one or more locations selected on extraluminal
images of the luminal segment, or by the operator viewing
indications of locations on an extraluminal image that correspond
to one or more locations selected with respect to endoluminal
images or an endoluminal image stack, as described with reference
to phase 7. Alternatively, a clinical diagnosis is made by the
operator reviewing the extraluminal images and/or the endoluminal
data (and/or by reviewing other data), without performing phase 7.
Typically, a therapeutic process, such as the one described in
phase 8 and beyond, is performed based upon the clinical diagnosis
made by the operator.
[0311] In phase 8, an endoluminal therapeutic device is inserted to
the designated location under extraluminal imaging. Typically,
stabilization (and optionally also enhancement) is applied,
typically on-line and typically automatically, to the extraluminal
image stream, in a generally similar manner to that described with
reference to phase 2. At least a portion of a therapy-applying
portion of the endoluminal therapeutic device, or a probe used for
the insertion of the therapeutic device (i.e., an insertion probe)
that moves with respect to the lumen, is typically visible in the
extraluminal images. For example, the therapy-applying portion may
include radiopaque markers, for applications in which the
extraluminal imaging is performed via fluoroscopy.
[0312] In phase 9, the current location of the moving, visible
portion of the endoluminal therapeutic device or the insertion
probe is determined, typically on-line and typically automatically.
Typically, the current location of the device is determined while
the device is at or in the vicinity of the designated site.
Typically, phase 9 is performed simultaneously with phase 8, i.e.,
while the endoluminal therapeutic device is at respective current
locations, the current location of the device is determined by the
system.
[0313] For some applications, the location of the portion of the
endoluminal therapeutic device or of the insertion probe that is
visible in the extraluminal imaging is identified via image
processing. For example, radiopaque markers on the endoluminal
therapeutic device may be identified in extraluminal fluoroscopic
images. For some applications, the visible portion is identified
and tracked, typically on-line and typically automatically, for
example, in accordance with techniques described in US 2010/0228076
to Blank.
[0314] For some applications, the location of the moving, visible
portion of the endoluminal therapeutic device or the insertion
probe is determined relative to an anatomical feature visible in
the extraluminal imaging. For some applications, the feature is a
bifurcation, a curve or some other unique shape, a partial or total
occlusion, a native valve, an aneurism, a septal defect, or a
malformation. For some applications, contrast agent is injected, in
order to make the feature visible (for example, in the case of
vasculature that is imaged under fluoroscopy). Typically, the
quantity and concentration of the contrast agent that is injected
is such that, in some image frames, both the visible portion of the
endoluminal data-acquisition device and the anatomical feature may
be discerned concurrently in the extraluminal image.
[0315] For some applications, the location of the moving, visible
portion of the endoluminal therapeutic device or the insertion
probe is determined relative to a previously-deployed device
visible in the extraluminal imaging. For some applications, the
device is a stent, or a graft, or a replacement valve.
[0316] For some applications, the location of the moving, visible
portion of the endoluminal therapeutic device or the insertion
probe is determined relative to visible markers along a guide wire
along which the device is inserted.
[0317] For some applications, the location of the moving, visible
portion of the endoluminal therapeutic device or the insertion
probe is determined according to its distance along a guide wire
along which the device and/or the probe is inserted, the distance
typically being measured relative to the distal tip of a guiding
catheter through which the guide wire was previously inserted. For
some applications, the endoluminal therapeutic device includes a
portion that substantially does not move with respect to the lumen
during a stage of the advancement of the therapy-applying portion
of the device, such as an insertion sheath. The location of moving,
visible portion of the endoluminal therapeutic device is
determined, via image processing, with reference to the portion of
the device that substantially does not move with respect to the
lumen.
[0318] For some applications, the location of the moving, visible
portion of the endoluminal therapeutic device or the insertion
probe is determined by determining a distance traveled by the
device along the lumen, from a known starting location. For some
applications, such a distance is measured by a pullback unit to
which the device is connected. For some applications, the distance
is measured by a longitudinal position/movement sensor coupled to
an apparatus through which the endoluminal data-acquisition device
is inserted, e.g., as described hereinbelow with reference to FIG.
2. For some applications, the apparatus is a guiding catheter.
Typically, the sensor measures the extent of longitudinal movement
(e.g., insertion, pullback) of a proximal portion of the device.
For some applications, the sensor is optical (e.g., laser-based),
or mechanical, or electric, or magnetic, or any combination
thereof. For some applications, in response to measuring the extent
of the longitudinal motion of the proximal portion of the device,
the system estimates a distance by which the therapy-applying
portion of the device has moved along the lumen (e.g., along a
center line of the lumen), typically automatically and typically
on-line. The center line is determined, typically automatically, in
accordance with techniques described in US 2010/0228076 to
Blank.
[0319] For some applications, the location of the moving, visible
portion of the therapeutic device is determined by means of display
coordinates. Typically, as described hereinabove, the current
location of the therapeutic device may be matched with a location
of the endoluminal data-acquisition device by using the same
viewing angle of the extraluminal imaging device relative to the
lumen, and by using zoom level of the extraluminal imaging, as were
used for the extraluminal imaging of the endoluminal
data-acquisition device.
[0320] In phase 10, data points (e.g., images) that were previously
acquired by the endoluminal data-acquisition device at or near the
location are retrieved and associated, typically on-line and
typically automatically, with the extraluminal imaging, while the
device is at or near the same location.
[0321] In phase 11, data points (e.g., images) that were previously
acquired by the endoluminal data-acquisition device at or near the
location are displayed together with the extraluminal imaging.
Typically, data points are displayed that correspond to the current
location of the endoluminal therapeutic device (as determined in
phase 9). Typically, phases 10 and 11 are performed in real time
with respect to phases 8 and 9. Thus, while the endoluminal
therapeutic device is at respective current locations inside the
lumen, the location of the device is determined, and the
endoluminal data points associated with the location are retrieved
and displayed.
[0322] For some applications, endoluminal and extraluminal images
corresponding to the same location (typically, the current location
of the endoluminal therapeutic device) are displayed side by side.
For some applications, endoluminal and extraluminal images
corresponding to the same location (typically, the current location
of the endoluminal therapeutic device) are merged, such as by means
of fusion or overlay. For some applications, quantitative vessel
analysis (QVA) data are displayed, the data typically corresponding
to the current location of the endoluminal therapeutic device.
Typically, the QVA data are generated automatically and on-line in
accordance with techniques described in US 2010/0228076 to Blank,
which is incorporated herein by reference. For example, the current
location of one or more markers of the therapeutic device may be
determined via image-processing, and QVA data corresponding to the
current location of the markers may be generated and displayed,
typically automatically, and typically on-line. Alternatively, in
response to a location within the lumen being indicated via a user
input device, QVA data corresponding to the location may be
generated and displayed, typically automatically, and typically
on-line.
[0323] For some applications, enhanced extraluminal images of a
lumen segment comprising the location are generated, for example,
in accordance with techniques described in US 2010/0228076 to
Blank, which is incorporated herein by reference.
[0324] For some applications (for example, in applications in which
the endoluminal data-acquisition device is an ultrasound probe),
image slices corresponding to a luminal segment at or around the
designated site are displayed as stacked.
[0325] Typically, the effect of co-displaying the endoluminal data
with the extraluminal imaging is as if the endoluminal therapeutic
device is being positioned and deployed under real-time
extraluminal imaging and using real-time endoluminal data
acquisition, at and in the vicinity of the designated site.
[0326] For some applications, phases 1 through 7 (or any applicable
subset of those phases) are repeated subsequent to the deployment
of the therapeutic device, such as in the course of performing a
clinical evaluation of the outcome of the deployment of that
device. For example, phases 1-7 may be repeated so as to facilitate
the co-display of endoluminal images of the lumen, post-deployment
of the device, with one or more extraluminal images of the
lumen.
[0327] For some applications, a procedure is carried out generally
in accordance with the flowchart shown in FIG. 1, in which one,
some, or all of the following apply: [0328] The luminal structure
is a coronary artery. [0329] The designated site for diagnosis and
treatment is a partially-occluded segment of the artery. [0330] The
endoluminal data-acquisition device is an IVUS probe, capable of
identifying coronary disease in the luminal wall. [0331] The
extraluminal imaging is performed via fluoroscopy. [0332] The
fluoroscopic image stream is, for some applications, stabilized
on-line. [0333] The endoluminal therapeutic device that is
positioned and deployed at the site of the occlusion is a
balloon-expandable stent. [0334] The balloon carrying the stent
comprises radio-opaque markers at its proximal and distal ends, the
markers being visible under fluoroscopic imaging.
[0335] For some such applications, images generated by the IVUS
probe within the coronary vessel are used in conjunction with the
extraluminal fluoroscopic image stream in the following manner:
[0336] i. An IVUS catheter is inserted to the site of an occlusion
under fluoroscopic imaging, to inspect endoluminal anatomy.
[0337] ii. Optionally, the fluoroscopic image stream is stabilized.
For some applications, the image stream is stabilized with respect
to radiopaque segments of the IVUS catheter.
[0338] iii. The image slices generated by the IVUS are recorded and
stored in tandem with the visual location (such as display
coordinates) of the distal tip of the IVUS catheter as seen by the
image-stabilized stream of the fluoroscopy.
[0339] iv. The IVUS catheter is retrieved to make room for
balloon/stent deployment.
[0340] v. A catheter with a balloon and/or stent is inserted to the
site of the occlusion, under fluoroscopic imaging.
[0341] vi. The location of the distal tip of the catheter carrying
the balloon and/or stent is visually recognized (such as via
display coordinates).
[0342] vii. The IVUS images previously recorded at the same
location are displayed, together with the fluoroscopic images. For
some applications, the IVUS images are displayed in a separate
window (but on the same screen as the fluoroscopic images). For
some applications, the IVUS images are displayed on a separate
screen. For some applications, the IVUS images being displayed are
two-dimensional (also known as "slices"). For some applications, a
stack comprising multiple slices is displayed. For some
applications, a three-dimensional "tunnel-like" reconstruction of
the IVUS images of the vessel (or a section thereof) is displayed.
For some applications, the IVUS images are overlaid on the
fluoroscopic images. For some applications, the IVUS images are
fused with the fluoroscopic images.
[0343] viii. As a result, the balloon and/or stent may be
positioned and deployed based upon an on-line combination of
real-time fluoroscopic images and of IVUS images recorded earlier
(for example, several minutes earlier).
[0344] For some applications, data acquired by a first endoluminal
modality (e.g., IVUS) are co-registered with the fluoroscopic image
stream, in accordance with the applications described hereinabove.
Subsequently, data acquired by a second endoluminal modality (e.g.,
OCT) are co-registered with the fluoroscopic image stream, in
accordance with the applications described hereinabove.
Consequently, due to both data sets being co-registered with the
fluoroscopic image stream, the two data sets are co-registered to
one another. For some applications, the two endoluminal data sets
are displayed as overlaid or otherwise merged with one another.
[0345] For some applications, generally similar steps to those
described with reference to FIG. 1 are performed, except for the
following differences. In phase 8, instead of a therapeutic
endoluminal device being inserted into the lumen, a second
endoluminal data-acquisition device is inserted into the lumen.
Typically, the first and second endoluminal data-acquisition
devices acquire endoluminal images using respective imaging
modalities. For example, in phase 3, an IVUS probe may be inserted
into the lumen, and in phase 8 an OCT probe may be inserted into
the lumen, or vice versa.
[0346] In phase 9, the current location of the second endoluminal
data-acquisition device is determined, for example, using any of
the techniques described herein (such as, by performing image
processing on extraluminal images of the second endoluminal
data-acquisition device inside the lumen). In phases 10 and 11,
endoluminal images which were previously acquired using the first
data-acquisition device at the current location of the second
endoluminal data-acquisition device are retrieved and displayed,
typically on-line and typically automatically.
[0347] Typically, the endoluminal images which were acquired using
the first data-acquisition device at the current location of the
second endoluminal data-acquisition device are displayed together
with endoluminal images that are being acquired in real time by the
second endoluminal data-acquisition device, while the second
endoluminal data-acquisition device is at the current location. For
some applications, endoluminal images that are acquired in real
time by the second endoluminal data-acquisition device, while the
second endoluminal data-acquisition device is at the current
location, are displayed together with an indication of the current
location of the second endoluminal data-acquisition device with
respect to an endoluminal image stack generated using endoluminal
images that were previously acquired by the first endoluminal
data-acquisition device. For some applications, using the
above-described technique, data acquired by first and second
endoluminal data acquisition devices are registered with respect to
one another, and the co-registered data are displayed subsequent to
termination of the acquisition of endoluminal images by both the
first and the second endoluminal data-acquisition devices. For some
applications, endoluminal images corresponding to the current
location of the second endoluminal data-acquisition device that
were acquired by the first endoluminal data acquisition device,
and/or by the second endoluminal data acquisition device, are
co-displayed with an indication of the current location of the
second endoluminal data-acquisition device on an extraluminal image
of the lumen, using the techniques described herein.
[0348] For some applications, techniques described herein (e.g.,
techniques described with reference to FIGS. 1-11) are performed by
a system that includes at least one processor, for use with an
endoluminal data-acquisition device that is configured to acquire a
set of endoluminal data-points with respect to a lumen of a body of
a subject at respective locations inside the lumen, and a second
endoluminal device. The processor typically includes (a)
location-association functionality configured to associate a given
endoluminal data point acquired by the endoluminal data-acquisition
device with a given location within the lumen, (b)
location-determination functionality configured, in an extraluminal
image of the second endoluminal device, to determine by means of
image processing, a current location of at least a portion of the
second endoluminal device inside the lumen, and (c) display-driving
functionality configured, in response to determining that the
second endoluminal device is currently at the given location, to
drive a display to display an indication of the endoluminal data
point associated with the given location.
[0349] Reference is now made to FIG. 2A-B, which are schematic
illustrations of an endoluminal device 31 (e.g., an IVUS probe)
being inserted into a lumen, and (in FIG. 2B) a sensor 36 for
sensing the distance traveled through the lumen by the endoluminal
device relative to a known starting location, in accordance with
some applications of the present invention. FIG. 2A shows IVUS
probe 31 being inserted, along a guide wire 32, through a guiding
catheter 33. Guiding catheter 33 is typically inserted through a
sheath 34 and is connected to a Y connector 35. FIG. 2B shows
sensor 36 disposed between guiding catheter 33 and Y connector 35.
Sensor 36 measures the longitudinal motion of a proximal portion of
IVUS probe 31 into (e.g., during insertion) and/or out of (e.g.,
during pullback/withdrawal) guiding catheter 33. For some
applications, the sensor is optical (e.g., laser-based),
mechanical, electric, magnetic, or any combination thereof. For
some applications, in response to measuring the longitudinal motion
of the proximal portion of the IVUS probe, the system estimates a
distance by which the data-acquisition portion of the IVUS probe
has moved along a the lumen (typically, along the center line of
the lumen), typically automatically and typically on-line. The
center line is determined, typically automatically, in accordance
with techniques described in US 2010/0228076 to Blank, which is
incorporated herein by reference.
[0350] It is noted that, for some applications, sensor 36 is used
for other endoluminal applications in which a luminal roadmap is
generated, and subsequently the sensor is used for determining the
current location of an endoluminal tool along the roadmap. For some
applications, the location of the endoluminal tool is determined
while the endoluminal tool is not being imaged by extraluminal
imaging. For some applications, the roadmap is generated and/or
utilized in accordance with techniques described in US 2008/0221442
to Tolkowsky, which is incorporated herein by reference. For some
applications, the roadmap is generated and/or utilized in
accordance with techniques described in US 2010/0160764 to
Steinberg, which is incorporated herein by reference.
[0351] Reference is now made to FIG. 3, which is a flow chart, at
least some of the steps of which are used in the course of co-use
of endoluminal data (e.g., generated by an IVUS probe) and
extraluminal imaging (e.g., fluoroscopic imaging), in accordance
with some applications of the current invention. It is noted that
although the steps described with reference to FIG. 3 are described
with reference to IVUS imaging, the scope of the present invention
includes applying these steps to any other forms of endoluminal
data-acquisition. It is noted that, for some applications, some of
the steps shown in FIG. 3 may be practiced without all of the steps
shown in FIG. 3 necessarily being practiced in combination.
[0352] In phase 1, an IVUS probe is inserted to the site of an
occlusion under fluoroscopic imaging, to acquire images of the
endoluminal anatomy.
[0353] In phase 2, the fluoroscopic image stream is typically
stabilized. For some applications, the image stream is stabilized
with respect to radiopaque segments of the IVUS probe.
[0354] In phase 3, the IVUS probe is stopped at a location that is
distal to the designated luminal site (the designated site being
the site of a lesion, for example, as described hereinabove).
[0355] In phase 4, contrast agent is injected and an angiogram
sequence is generated, under fluoro or cine.
[0356] In phase 5, an initial best angiogram frame is selected,
typically automatically and typically on-line. The initial best
angiogram frame is typically selected based upon the following
criteria: (a) the frame is acquired at a desired cardiac phase
(typically end diastole) (b) in the image frame, contrast agent
highlights the vessel, and (c) radiopaque elements (such as
markers) at the distal section (i.e., in the vicinity of the
imaging sensor) of the IVUS probe are visible in the image
frame.
[0357] Reference is now made to FIG. 4, which shows an initial best
angiogram of lumen 21, in accordance with some applications of the
present invention. As shown in FIG. 4, radiopaque markers 22 of the
IVUS probe are typically seen distally to lesion 23 in the initial
best angiogram.
[0358] In phase 6, pullback of the IVUS probe, typically at a known
and steady rate of distance per second (such as by means of
automated pullback), commences. The image slices generated by the
IVUS probe along the pullback are recorded and stored in an image
sequence. For some applications, the pullback is performed
manually.
[0359] For some applications, the image slices generated by the
IVUS probe along the pullback are recorded and stored in an image
sequence, and simultaneously, a longitudinal position/movement
sensor attached to apparatus through which the IVUS probe is
inserted measures the longitudinal location of a proximal portion
of the IVUS probe relative to the starting location of the proximal
portion of the probe, e.g., as described with reference to FIG. 2.
The locations of the IVUS probe as determined by the sensor, when
respective IVUS image slices were recorded, are stored by the
system.
[0360] For some applications, in the course of pullback, the lumen
also experiences cyclical motion (typically due to the cardiac
cycle) that causes it to pulsate and move back and forth relatively
to the IVUS probe. For some applications, e.g., in the case of a
lumen that undergoes such back-and-forth cyclical motion, data
acquired by the IVUS probe is gated to the cyclical motion cycle of
the lumen. Subsequently, IVUS images acquired in the course of the
pullback at at-least-one specific phase (for example, an
end-diastolic phase) of the motion cycle of the lumen are
co-registered with one or more fluoroscopic images acquired, and
gated, at the corresponding at-least-one phase during the pullback,
in order to facilitate the co-registration of the IVUS images to
the fluoroscopic images. For some applications, co-registering IVUS
images with angiographic images that are gated to the same phase as
the phase to which the IVUS images were gated, reduces distortions
to the co-registration that may be introduced due to the cyclical
motion of the lumen in the absence of using the aformentioned
gating techniques.
[0361] For some applications, as described hereinbelow, in a
subsequent phase (e.g., phase 13), in response to the user
indicating location on the extraluminal image, the system retrieves
and displays a corresponding endoluminal image frame, typically
automatically and typically on-line. For some applications, the
system displays the closest gated endoluminal image frame
corresponding to the location indicated by the user, even though
there may be a non-gated image frame the location of which more
closely corresponds to the location indicated by the user.
Alternatively, the system displays the endoluminal image frame the
location of which most closely corresponds to the location
indicated by the user, irrespective of the phase of the cardiac
cycle at which the endoluminal image frame was acquired.
[0362] For some applications, there is a single, gated extraluminal
angiogram image to which all gated endoluminal data are
co-registered. For some applications, a three-dimensional model is
generated from two (or more) two-dimensional gated angiograms, and
the gated endoluminal data is co-registered with that
three-dimensional model.
[0363] For some applications, the commencement of pullback is
identified, typically automatically and typically on-line, by means
of image processing. For some applications, the image processing is
performed by an image comparator which identifies a significant
change (such as in the color of image pixels or in the geometry of
image features) in the sequentially-acquired endoluminal images,
and interprets the change as indicating the commencement of
pullback. For some applications, the commencement of pullback is
identified by means of a signal transmitted by the pullback unit
and/or by the endoluminal data acquisition system. For some
applications, the commencement of pullback is indicated by means of
user input.
[0364] In phase 7, the pullback is stopped at a location that is
proximal to the designated lesion. For some applications, the
termination of pullback is identified, typically automatically and
typically on-line, by means of image processing. For some
applications, the image processing is performed by an image
comparator which identifies a diminishing change in the
sequentially-acquired endoluminal images, and interprets the
diminishing change as indicating the termination of pullback. For
some applications, the termination of pullback is identified by
means of a signal transmitted by the pullback unit and/or by the
endoluminal data acquisition system. For some applications, the
termination of pullback is indicated by means of user input.
[0365] In phase 8, contrast agent is injected and an angiogram
sequence, under fluoro or cine, is generated.
[0366] In phase 9, a post-pullback best angiogram frame is
selected, typically automatically and typically on-line. The
post-pullback best angiogram frame is typically selected based upon
the following criteria: (a) the frame is acquired at a desired
cardiac phase (typically end diastole) (b) in the image frame,
contrast agent highlights the vessel, and (c) radiopaque elements
(such as markers) at the distal section (i.e., in the vicinity of
the imaging sensor) of the IVUS probe are visible in the image
frame.
[0367] Reference is now made to FIG. 5, which shows a post-pullback
best angiogram of lumen 21, in accordance with some applications of
the present invention. As shown in FIG. 5, radiopaque markers 22 of
the IVUS probe are typically seen proximally to lesion 23, in the
post-pullback best angiogram.
[0368] In phase 10, the initial best angiogram and the
post-pullback best angiogram are co-registered to one another,
typically automatically and typically on-line, according to
techniques described in US 2010/0222671 to Cohen, which is
incorporated herein by reference. A combined best angiogram is
generated by co-registering the initial and post-pullback best
angiograms. Typically, in the combined best angiogram, the vessel
and two sets of the IVUS probe's radiopaque elements (one of the
sets being from the initial best angiogram and the second set being
from the post-pullback best angiogram) are visible.
[0369] Alternatively, the combined best angiogram is generated by
adding the markers that are visible in the initial best angiogram
onto the post-pullback best angiogram using the aforementioned
registration techniques. Further alternatively, the combined best
angiogram is generated by adding the markers that are visible in
the post-pullback best angiogram onto the initial best angiogram
using the aforementioned registration techniques.
[0370] Reference is now made to FIG. 6, which shows a combined best
angiogram of lumen 21, in accordance with some applications of the
invention. As shown in FIG. 6, distal radiopaque markers 22 of the
IVUS probe are shown (e.g., overlaid) at their locations before and
after the pullback on the combined best angiogram of the lumen.
[0371] In phase 11, a center line typically is generated on the
combined best angiogram (for example, in accordance with the
techniques described in US 2010/0220917 to Steinberg, which is
incorporated herein by reference) from the proximal to the distal
marker locations along the vessel. The system generates an index of
the IVUS slices, based upon the estimated location of the IVUS
probe marker (from the distal-most marker location the
proximal-most marker location) along the lumen (and typically along
the center-line), at the time of acquisition of respective
slices.
[0372] For some applications, the system interpolates between the
distal-most location of the IVUS marker along the lumen (e.g.,
along the center line of the lumen) and the proximal-most location
of the IVUS marker along the lumen (e.g., along the center line),
in order to determine the location of the IVUS marker corresponding
to intermediate IVUS slices. For some applications, in indexing the
IVUS slices between the proximal-most and distal-most slices, it is
assumed that pullback of the IVUS probe was performed at a linear
rate, and that there is therefore an equal distance between any
pair of adjacent IVUS slices, and any other pair of adjacent IVUS
slices (i.e., it is assumed that between acquiring respective
successive pairs of slices, the probe traveled equal distances).
For some applications, in indexing the IVUS slices between the
proximal-most and distal-most slices, the system accounts for the
IVUS probe acquiring IVUS images at varying frame rates.
[0373] In phase 12, the IVUS probe is retrieved.
[0374] In phase 13, while observing angiographic images of the
luminal segment comprising the designated location, one or more
locations along that section are indicated by a user input device.
Typically, the user designates a location using the user input
device, and the system identifies a location along the lumen
(typically, along the luminal center line) as corresponding to the
designated location, and retrieves the previously-acquired IVUS
images corresponding to the location, based upon the indexing of
the IVUS frames. The retrieved endoluminal image frames previously
recorded at the selected location are displayed.
[0375] Alternatively, by observing an angiogram frame side by side
with endoluminal image frames of the luminal segment comprising the
designated location, one or more locations along the section are
indicated by a user input device with respect to endoluminal
imaging data. For some applications, the user indication is made
upon the endoluminal image stack. For some applications, the user
indication is made by browsing through the endoluminal images. In
response to receiving the user indication, the location along the
lumen (e.g., along the luminal center line) within the angiogram
corresponding to the location indicated with respect to an
endoluminal image or the endoluminal image stack is determined and
indicated. For some applications, the corresponding location on the
angiogram is determined based upon the indexing of the IVUS slices,
based upon the location of the IVUS probe marker along the lumen
(e.g., along the luminal center-line), at the time of acquisition
of respective slices, as described hereinabove with reference to
phase 11.
[0376] For some applications, the location corresponding to the
location indicated with respect to the endoluminal image frames or
the endoluminal image stack is displayed on the combined best
angiogram. Alternatively, (in cases in which a plurality of
angiograms are acquired during pullback, as described hereinbelow)
the location is displayed on the angiogram that was acquired
closest in time to the acquisition of the endoluminal image frame
indicated by the user input device.
[0377] Reference is now made to FIG. 7, which is schematic
illustration of a screen on which an IVUS image 83 is displayed, in
accordance with some applications of the present invention.
Typically, upon receiving an indication from the user of a location
along the lumen (e.g., along the luminal center line 82, for
example, by the user pointing cursor 81 to a location on the
screen, and the system determining a location along the center line
corresponding to the location), IVUS image 83 which was previously
acquired at that location is displayed. For some applications, an
IVUS stack comprising data from IVUS images that were previously
acquired along a section of the lumen (e.g., along a section of
center line 82) of which the user-indicated location is a middle
point or one of the end points, is displayed. For some
applications, an IVUS stack comprising data from IVUS images that
were previously acquired between two user-indicated locations along
the lumen (e.g., along center line 82) is displayed.
[0378] Typically, a clinical diagnosis is facilitated by an
operator viewing previously-acquired endoluminal images
corresponding to the one or more locations selected on extraluminal
images of the luminal segment, or by the operator viewing
indications of locations on an extraluminal image that correspond
to one or more locations selected on endoluminal images, as
described with reference to phase 13. Alternatively, a clinical
diagnosis is made by the operator reviewing the extraluminal images
and/or the endoluminal data (and/or reviewing other data), without
performing phase 13. Typically, a therapeutic process, such as the
one described in phase 14 and beyond, is performed based upon the
clinical diagnosis made by the operator.
[0379] In phase 14, a catheter with a balloon and/or stent is
inserted to the area of the designated site, under fluoroscopic
imaging. Typically, the fluoroscopic image stream is stabilized
with respect to radiopaque markers on the catheter via which the
balloon and/or the stent is inserted.
[0380] In phase 15, upon reaching a desired location within the
blood vessel (such as the vicinity of the designated site),
contrast agent is injected and an angiogram sequence is generated
under fluoro or cine.
[0381] In phase 16, a current best angiogram frame is selected,
typically automatically and typically on-line. The current best
angiogram frame is typically selected based upon the following
criteria: (a) the frame is acquired at a desired cardiac phase
(typically end diastole) (b) in the image frame, contrast agent
highlights the vessel, and (c) radiopaque elements (such as
markers) at the distal section (i.e., in the vicinity of the
imaging sensor) of the balloon/stent catheter are visible in the
image frame.
[0382] In phase 17, the combined best angiogram and the current
best angiogram are co-registered to one another, typically
automatically and typically on-line, according to techniques
described in 2010/0222671 to Cohen, which is incorporated herein by
reference. A multi-combined best angiogram is generated by
co-registering the combined and current best angiograms. Typically,
in the multi-combined best angiogram, the vessel and the two sets
of the IVUS probe's radiopaque elements (one of the sets being from
the initial best angiogram and the second set being from the
post-pullback best angiogram) and the radiopaque markers of the
balloon/stent catheter are visible.
[0383] In phase 18, a user and/or the system selects a location of
interest along the lumen in the multi-combined best angiogram of
the lumen. For example, a user or the system may select a location
of a point of interest along the balloon/stent (such as the
location of one of the balloon/stent markers, or anywhere in
between the markers).
[0384] In phase 19, based upon the indexing described hereinabove,
with reference to phase 11, the IVUS image previously recorded at
the selected location (which is typically based upon the current
location of the balloon/stent catheter, as described in the
previous step (step xvi)) is identified. The corresponding IVUS
image is retrieved and displayed, typically automatically and
typically on-line, together with the fluoroscopic images. For some
applications, the IVUS images are displayed in a separate window
(but on the same screen as the fluoroscopic images). For some
applications, the IVUS images are displayed on a separate screen.
For some applications, the IVUS images that are displayed are
two-dimensional (also known as "slices"). For some applications, a
stack comprising multiple IVUS slices (such as those corresponding
to the longitudinal section between the current locations of the
proximal and distal markers of the balloon/stent, and, optionally,
beyond the aforementioned current marker locations, in each
direction) is displayed.
[0385] For some applications, a three-dimensional "tunnel-like"
reconstruction of the IVUS images of the vessel (or a section
thereof, such as those corresponding to the longitudinal section
between the current locations of the proximal and distal markers of
the balloon/stent) is generated and displayed. For some
applications, the IVUS images are overlaid on the fluoroscopic
images. For some applications, the IVUS images are fused with the
fluoroscopic images. For some applications, a combination of the
aforementioned display techniques is applied. For some
applications, an indication of the motion range of the
balloon/stent relative to the lumen, resulting from the cardiac
cycle, is displayed in conjunction with any of the aforementioned
displays of the IVUS images. For some applications, such an
indication is generated and/or displayed in accordance with
embodiments of US 2010/0222671 to Cohen, which is incorporated
herein by reference.
[0386] As an alternative or in addition to phases 18 and 19, by
observing an angiogram frame (e.g., the multi-combined best
angiogram) side by side with endoluminal image frames of the
luminal segment comprising the designated location, one or more
locations along the section are indicated by a user input device
with respect to endoluminal imaging data. For some applications,
the user indication is made upon the endoluminal image stack. For
some applications, the user indication is made by browsing through
the endoluminal images. In response to receiving the user
indication, the location along the lumen (e.g., along the luminal
center line) within the angiogram frame (e.g., the combined best
angiogram) corresponding to the location indicated with respect to
the endoluminal image or the endoluminal image stack is determined
and indicated.
[0387] In phase 20, as a result of displaying the IVUS image or an
image derived from the IVUS image (e.g., a fused image), the
balloon and/or stent may be positioned and deployed based upon an
on-line combination of real-time fluoroscopic images and of IVUS
images recorded earlier (for example, more than a minute
earlier).
[0388] Although phases 14-20 have been described with respect to
inserting a balloon and a stent into the lumen, the scope of the
present invention includes performing steps 14-20 in conjunction
with a different therapeutic device being inserted into the lumen,
mutatis mutandis. For example, a guide wire may be inserted into
the lumen in order to penetrate an occlusion (e.g., a total
occlusion) of the lumen. A radiopaque marker that is visible in
extraluminal images (e.g., fluoroscopic and/or angiographic images)
is disposed at the distal end of the guidewire. By applying phases
14-20 in conjunction with the insertion of the guidewire through
the occlusion, the system facilitates the retrieval and display of
endoluminal images (e.g., OCT and/or IVUS images) of the lumen that
correspond to the current location of the radiopaque marker of the
guidewire. For some applications, the system facilitates the
display of the current location of the radiopaque marker of the
guidewire with respect to a previously-acquired endoluminal image
stack of the lumen.
[0389] Typically, in the case of a total occlusion of the lumen, it
is not possible to acquire endoluminal images of the occluded
segment of the lumen, since the occluded segment is closed. For
some applications, in such cases, a forward-looking endoluminal
imagining probe is used to acquire endoluminal images of segments
of the lumen that are distal to the probe, while the probe is at
respective locations within the lumen. Subsequently, when a
guidewire is inserted through the lumen, in order to penetrate the
occlusion, an endoluminal image of a segment of the lumen that is
distal to the guidewire corresponding to the current location of
the guidewire is shown, using the co-registration techniques
described herein. Alternatively, when the guidewire is inserted
through the lumen the current location of the tip of the guidewire
is displayed with respect to an endoluminal image stack of the
lumen, the stack being based upon the previously-acquired
endoluminal images.
[0390] As described hereinabove with reference to FIG. 3, for some
applications, initial and post-pullback angiograms are generated in
order to determine the locations of the IVUS markers with respect
to the lumen before and after pullback. Intermediate marker
locations corresponding to intermediate endoluminal images are
indexed by interpolating between distal and proximal marker
locations that are determined based upon, respectively, the initial
and post-pullback angiograms. Typically, in indexing the IVUS
slices between the proximal-most and distal-most slices, it is
assumed that pullback of the IVUS probe was performed at a linear
rate and that the frame rate of the IVUS probe was constant. It is
therefore assumed that there is an equal distance between any pair
of adjacent IVUS slices, and any other pair of adjacent IVUS
slices.
[0391] Alternatively, as described hereinabove, the system
estimates the speed of the pullback of the imaging head of the IVUS
probe by measuring the speed of the pullback of a proximal portion
of the probe, using a sensor, e.g., as described with reference to
FIG. 2. Thus, the system may determine an initial location of the
IVUS markers by acquiring an initial angiogram, and may determine
subsequent locations of the IVUS markers based upon the estimated
speed of the pullback of the IVUS probe and the time that has
elapsed between the commencement of pullback and the estimated
speed of the pullback.
[0392] Further alternatively, as described hereinbelow with
reference to FIG. 8, pullback of the endoluminal imaging probe is
performed while the lumen is continuously flushed with contrast
agent. This is applicable, for example, in the case of an
endoluminal OCT probe, as described hereinbelow. For example, in
such cases, the lumen may be continuously flushed with contrast
agent for a time period of at least two seconds, and/or for at
least 50% (e.g., at least 80%) of the duration of a time period
over which the imaging probes acquires the endoluminal images
during pullback. In such cases, the entire pullback procedure (or
an entire portion thereof) may be performed under angiographic
imaging. The endoluminal probe marker locations corresponding to
given endoluminal images are determined by identifying marker
locations in the angiographic images (e.g., via image processing
that is typically performed automatically and on-line),
co-registering the angiographic images into a combined best
angiogram, and indexing the identified marker locations with
respect to the endoluminal images, as described hereinbelow.
Intermediate marker locations that do not appear in the combined
best angiogram are estimated, as described hereinbelow, with
reference to FIG. 8. The aforementioned technique may be typically
used to determine marker locations even in cases in which the
pullback of the endoluminal imaging probe is not performed at a
constant speed, since marker locations that are known are typically
relatively close to one another.
[0393] Still further alternatively, endoluminal probe marker
locations corresponding to respective endoluminal images are
determined, by acquiring fluoroscopic images of the probe within
the lumen during the pullback (the fluoroscopic images typically
being acquired without requiring the injection of contrast
materials). The endoluminal probe marker locations corresponding to
given endoluminal images are determined by identifying marker
locations in the fluoroscopic images (e.g., via image processing)
and indexing the identified marker locations with respect to the
endoluminal images. Typically, the radiopaque markers of the probe
are identified, typically automatically and typically on-line, and
their locations are determined, typically automatically and
typically on-line, according to their distances along a guide wire
along which the probe is inserted. For some applications, the
distances are measured relative to the distal tip of a guiding
catheter through which the guide wire was previously inserted.
Alternatively, the marker locations are measured relative to other
portions of the apparatus that are visible in the fluoroscopic
images and that are substantially stationary with respect to the
lumen during pullback of the probe, as described hereinabove with
reference to phase 5 of the flowchart shown in FIG. 1. The
aforementioned technique may be used to determine marker locations
even in cases in which the pullback of the endoluminal imaging
probe is not performed at a constant speed.
[0394] For some applications, the determination of marker locations
is generally as described with reference to FIG. 3. That is,
initial and post-pullback angiograms are generated in order to
determine the locations of the IVUS markers with respect to the
lumen before and after pullback, and intermediate marker locations
corresponding to intermediate endoluminal images are indexed by
interpolating between known marker locations. However, as described
hereinabove, in indexing the IVUS slices between the slices that
were acquired at known marker locations, it is typically assumed
that pullback of the IVUS probe was performed at a linear rate, and
that there is therefore an equal distance between any pair of
adjacent IVUS slices, and any other pair of adjacent IVUS slices.
For some applications, in order to overcome errors in the estimated
marker locations due to non-linear pullback of the probe (and/or
for a different reason), additional intermediate marker locations
are identified. Marker locations between the identified marker
locations are indexed by interpolating between the two closest
identified marker locations, and not just by interpolating between
the distal-most and proximal-most marker locations. Typically, such
a technique reduces errors in estimating the intermediate marker
locations due to a non-linear pullback rate of the endoluminal
imaging probe, relative to a technique in which only the
distal-most and proximal-most marker locations are identified.
[0395] For some applications, the additional marker locations are
determined by acquiring additional angiograms in between the
acquisition of the initial angiogram and the post-pullback
angiogram. For each of these angiograms, the endoluminal imaging
probe marker is identified, and the best frame is selected,
typically in accordance with the techniques described herein. The
marker location is typically co-registered with the combined best
angiogram, in accordance with the techniques described herein.
Based on the marker locations that are derived from the
intermediate angiograms, a plurality of known marker locations are
thereby determined with respect to the combined best angiogram. The
system indexes IVUS slices at any section along the lumen (e.g.,
along the luminal center line) within the combined best angiogram
by interpolating the marker locations corresponding to respective
IVUS slices with reference to the two closest known IVUS marker
locations to that section.
[0396] Alternatively, intermediate marker locations are determined
by identifying a feature in an endoluminal image that is also
identifiable in the combined best angiogram (or in an angiogram
that is co-registered to the combined best angiogram). In response
thereto, the location of the endoluminal probe marker at the
acquisition of the endoluminal image may be determined with respect
to the combined best angiogram. For some applications, the feature
is a bifurcation, a curve or some other unique shape, a partial or
total occlusion, a native valve, an aneurism, a septal defect, or a
malformation. For some applications, the feature is a
previously-deployed device visible in the extraluminal imaging. For
some applications, the previously-deployed device is a stent, or a
graft, or a replacement valve.
[0397] It is noted that in applying any of the techniques described
hereinabove for associating endoluminal images with respective
locations along the lumen, the system typically accounts for a
known offset between the location of the moving, visible portion of
the endoluminal imaging probe (e.g., a radiopaque marker), and the
location of the image-acquiring portion of the probe (e.g., the
ultrasound transducer, in the case of an IVUS probe).
[0398] It is noted that some of the techniques described
hereinabove for associating endoluminal images with respective
locations along the lumen are described with reference to an
endoluminal imaging probe that acquires endoluminal images during
pullback of the probe. The scope of the present invention includes
applying any of the techniques described hereinabove for
associating endoluminal images with respective locations along the
lumen to an endoluminal imaging probe that acquires endoluminal
images during insertion and advancement of the probe through the
lumen (e.g., when images are acquired from an endobronchial
airway), mutatis mutandis.
[0399] In general, when applying the techniques described herein,
in indexing endoluminal image frames at any point along the lumen
(e.g., along the luminal center line) with reference to the two
closest identified marker locations to the point, it is typically
assumed that pullback of the endoluminal probe and the acquisition
of images by the endoluminal probe were performed at linear rates,
and that there is therefore an equal distance between any pair of
adjacent endoluminal images, and any other pair of adjacent
endoluminal images that were acquired between the two closest
identified locations of the endoluminal probe. For some
applications, in indexing the endoluminal images at any point along
the lumen (e.g., along the luminal center line) with reference to
the two closest identified marker locations to the point, the
system accounts for the probe acquiring endoluminal images at
varying frame rates, and/or for pullback being performed at a
non-linear rate (the rate of pullback in such cases, typically
being estimated, based upon measurements of a sensor, as described
with reference to FIG. 2).
[0400] For some applications, techniques described herein (e.g.,
techniques described with reference to FIGS. 1-11) are performed by
a system that includes at least one processor. The processor is
typically for use with an endoluminal data-acquisition device
configured to acquire a plurality of endoluminal data points of a
lumen of a body of a subject at respective locations inside the
lumen, while the endoluminal data-acquisition device is moved
through the lumen, the endoluminal data-acquisition device having a
radiopaque marker coupled thereto. The processor is typically for
use with an angiographic imaging device configured to acquire
respective angiographic image of the lumen, at times associated
with acquisitions of respective endoluminal data point by the
endoluminal data-acquisition device. For some applications, the
processor includes location-association functionality configured to
determine first and second locations of the radiopaque marker
respectively within first and second angiographic images of the
lumen. For some applications, the processor includes
image-co-registration functionality configured to generate a
combined angiographic image of the lumen that includes
representations of the first and second marker locations thereon,
by co-registering the first and second angiographic images. For
some applications, the processor includes location-association
functionality configured to determine that at least one location on
the combined angiographic image that is intermediate to the first
and second locations of the radiopaque marker corresponds to an
endoluminal data point acquired between the acquisitions of first
and second data points corresponding to the first and second
locations of the marker, by interpolating between the first and
second locations of the radiopaque marker on the combined
angiographic image. Typically, the processor includes
display-driving functionality configured to drive the display to
display an output, in response to determining that the intermediate
location corresponds to the endoluminal data point acquired between
the acquisitions of the first and second data points.
[0401] For some applications, the image-co-registration
functionality is configured to generate the combined angiographic
image of the lumen that includes representations of the first and
second marker locations thereon, by co-registering the first and
second angiographic images to one another, by designating one of
the angiographic images as a baseline image, a shape of the lumen
in the baseline image being designated as a baseline shape of the
lumen. The image-co-registration functionality typically determines
whether a shape of the lumen in the angiographic image that is not
the baseline image is the same as the baseline shape of the lumen,
and in response to determining that the shape of the lumen in the
angiographic image that is not the baseline image is not the same
as the baseline shape of the lumen designates the image that is not
the baseline image as a non-baseline image. The
image-co-registration functionality typically deforms the shape of
the lumen in the non-baseline image, such that the shape of the
lumen becomes more similar to the baseline shape of the portion
than when the lumen in the non-baseline image is not deformed, and
based upon the deformation of the non-baseline image, determines a
location upon the baseline image at which the marker from within
the non-baseline image should be located. The image-co-registration
functionality typically generates an indication of the marker from
within the non-baseline image at the determined location on the
baseline image. For some applications, the image-co-registration
functionality is configured to generate the combined angiographic
image of the lumen using similar techniques to those described in
US Patent Application 2010/0172556 to Cohen et al., which is
incorporated herein by reference.
[0402] For some applications, techniques described herein (e.g.,
techniques described with reference to FIG. 3) are performed by a
system that includes at least one processor. The processor is
typically for use with (a) an endoluminal data-acquisition device
configured to acquire a plurality of endoluminal data points of a
lumen of a body of a subject at respective locations inside the
lumen, while the endoluminal data-acquisition device is being moved
through the lumen, the endoluminal data-acquisition device having a
radiopaque marker coupled thereto, (b) contrast agent configured to
be continuously injected into the lumen, during the movement of the
endoluminal data-acquisition device, and (c) an angiographic
imaging device configured to acquire a plurality of angiographic
images of the endoluminal data-acquisition device inside the lumen,
during the movement of the endoluminal data-acquisition device. The
processor typically includes (a) location-association functionality
configured to determine that endoluminal data points correspond to
respective locations within the lumen, by determining locations of
the radiopaque marker within the angiographic images of the lumen,
by performing image processing on the angiographic images, the
locations of the radiopaque marker within the angiographic images
of the lumen corresponding to respective endoluminal data points,
and (b) display-driving functionality configured to drive the
display to display an output, in response to determining that the
endoluminal data points correspond to respective locations within
the lumen.
[0403] For some applications, phases 1 through 13 (or any
applicable subset of those phases) of FIG. 3, are repeated
subsequent to the deployment of the therapeutic device, such as in
the course of performing a clinical evaluation of the outcome of
the deployment of that device. For example, phases 1-13 may be
repeated so as to facilitate the co-display of endoluminal images
of the lumen, post-deployment of the device, with one or more
extraluminal images of the lumen.
[0404] For some applications, pullback of the endoluminal
data-acquisition device is performed in the course of a continuous
injection of contrast agent performed under fluoroscopic imaging.
For example, the endoluminal data-acquisition device may be an OCT
probe, the image acquisition of which typically requires concurrent
flushing of the lumen, in order to remove blood from the lumen, the
blood interfering with the OCT imaging. Furthermore, contrast agent
highlights the lumen and facilitates angiographic imaging of the
lumen. Still furthermore, for some applications, the presence of
contrast agent in the lumen facilitates acquisition of OCT data.
Therefore, typically, during endoluminal imaging with an OCT probe,
contrast agent is continuously injected into the lumen. In
addition, the pullback of the OCT probe is typically performed
rapidly relative to the pullback of an IVUS probe, and the frame
acquisition rate of the OCT probe is typically greater than that of
an IVUS probe.
[0405] For endoluminal imaging techniques such as OCT techniques,
in which pullback of the imaging probe is performed under constant
angiographic imaging, phases 4 to 10 of the technique described
with reference to the flowchart shown in FIG. 3 may be substituted
or combined with the phases described below. The steps described
below are typically performed in conjunction with at least some of
the other phases described with reference to the flowchart shown in
FIG. 3, mutatis mutandis. Although the steps below are described
with reference to endoluminal imaging with an OCT probe, the scope
of the present invention includes performing these steps when using
a different endoluminal imaging probe (such as an IVUS probe), the
pullback of which is performed under constant angiographic
imaging.
[0406] Pullback of the OCT probe commences (for example, by means
of manual pullback, or at a known and steady rate of distance per
second, such as by means of automated pullback), in conjunction
with contrast agent injection performed under fluoroscopic imaging.
The image slices generated by the OCT along the pullback are
recorded and stored, synchronized (such as by time or by frame
number) with the corresponding stored angiographic images. In
addition, the locations of the OCT markers corresponding to
respective, at least some OCT image slices are stored with
reference to the corresponding stored angiographic image. For some
applications, the marker locations are determined by identifying
the markers in the angiographic images by (typically automatically)
performing image processing on the angiographic images.
[0407] The total number of OCT images and fluoroscopic images
acquired during the pullback may differ (due to different image
acquisition frame rates). For example, the fluoroscopy frame rate
may be 25 frames per second, whereas the OCT frame rate may be 100
frames per second, in which case OCT frames 1 through 4 are indexed
to fluoroscopy frame 1, OCT frames 5 through 8 are indexed to
fluoroscopy frame 2, etc.
[0408] From along the contrast injection in the course of the
pullback, the system selects an angiogram frame, typically
according to criteria described hereinabove, and depicts upon that
frame the locations of the radiopaque marker(s) of the OCT probe,
in whole or in part, by means of image processing, during pullback.
The selected angiogram is denoted as the combined best angiogram.
For some applications, and typically pursuant to the selection of
the combined best angiogram, non-rigid transformation of one or
more angiogram frames from the pullback sequence to the combined
best angiogram is performed, typically automatically and typically
on-line. The non-rigid transformation is typically followed by the
depiction of the locations of the radiopaque marker(s) of the OCT
probe on the resulting combined best angiogram, typically
automatically and typically on-line. In depicting the marker
locations on the resulting combined best angiogram, the non-rigid
transformation of angiographic image frames associated with
respective marker locations is accounted for. For some
applications, such non-rigid transformation and marker depiction
are performed according to techniques described in 2010/0222671 to
Cohen, which is incorporated herein by reference.
[0409] Reference is now made to FIG. 8 which shows a combined best
angiogram, the combined best angiogram having been created in the
course of a sequence for use in conjunction with an OCT endoluminal
imaging probe, as described hereinabove, in accordance with some
applications of the present invention. As shown, known OCT probe
marker locations are shown on the combined best angiogram.
Typically, even in cases in which pullback is performed under
continuous angiographic imaging, not all of the marker locations
are known, since the frame rate of the OCT probe is typically
greater than the frame rate of the x-ray imager. The endoluminal
probe marker locations corresponding to given endoluminal images
that are not identifiable in the angiographic image are determined
by indexing the marker locations with respect to the endoluminal
images.
[0410] For example, in order to determine which is the endoluminal
image corresponding to the point along the lumen in the combined
best angiogram indicated by the double arrow in FIG. 8, it is
determined that the OCT probe marker is a given distance between
the marker locations that are identifiable in a given pair of
angiograms. Based upon the times of the acquisitions of the given
pair of angiograms, the rate at which the angiograms were acquired,
and the rate at which the OCT frames were acquired, the OCT frame
corresponding to that point may be determined.
[0411] For example, if the frame rate of the angiograms is 25 per
second, the pair of angiograms were acquired, respectively at 0.7
seconds and 1.8 seconds from a given starting time, and the
indicated location is one third of the distance between the marker
locations known from the pair of angiograms, then it is determined
that the corresponding OCT image was acquired at 1.06 seconds after
the starting time, by performing the following calculation:
(0.33*(1.8-0.7)+0.7)=1.06
[0412] Thus, if the frame rate of the OCT probe is 100 frames per
second, the corresponding OCT frame is frame 106.
[0413] Reference is now made to FIG. 9, which shows the co-display
of previously-acquired endoluminal image frames (e.g., frame 91),
the endoluminal locations of the endoluminal imaging probe at the
time of the acquisition of respective image frames being indicated
on an extraluminal image of the lumen, the locations having been
automatically indentified during pullback of the endoluminal
imaging probe, in accordance with some applications of the present
invention. For some applications, previously-acquired endoluminal
OCT images frames (or other forms of endoluminal image frames) are
connected by lines, to the corresponding endoluminal locations
(such as location 92), of the OCT imaging probe at the times that
the OCT image frames were acquired. For some applications, the
range of the pullback is indicated with respect to an OCT image
stack 94. For example, a line 93 is generated on the OCT image
stack indicating where the pullback ended. For some applications,
some endoluminal locations, such as location 92, are indicated as
being associated with a corresponding location on the endoluminal
image stack. For example, a line that is similar to line 93 may be
generated on OCT image stack 94 to indicate the location on the
image stack that corresponds to location 92.
[0414] For some applications, data acquired by a first endoluminal
modality (e.g., IVUS) are co-registered with the fluoroscopic image
stream, in accordance with the applications described hereinabove.
Subsequently, data acquired by a second endoluminal modality (e.g.,
OCT) are co-registered with the fluoroscopic image stream, in
accordance with the applications described hereinabove.
Consequently, due to both data sets being co-registered with the
fluoroscopic image stream, the two data sets are co-registered to
one another. For some applications, the two endoluminal data sets
are displayed as overlaid or otherwise merged with one another.
[0415] For some applications, generally similar steps to those
described with reference to FIG. 3 are performed, except for the
following differences. In phase 14, instead of a therapeutic
endoluminal device (e.g., a treatment catheter) being inserted into
the lumen, a second endoluminal data-acquisition device is inserted
into the lumen. Typically, the first and second endoluminal
data-acquisition devices acquire endoluminal images using
respective imaging modalities. For example, in phase 1, an IVUS
probe may be inserted into the lumen, and in phase 14 an OCT probe
may be inserted into the lumen, or vice versa.
[0416] The current location of the second endoluminal
data-acquisition device is determined, for example, using any of
the techniques described herein (such as, by performing image
processing on extraluminal images of the second endoluminal
data-acquisition device inside the lumen). Endoluminal images which
were previously acquired using the first data-acquisition device at
the current location of the second endoluminal data-acquisition
device are retrieved and displayed, typically on-line and typically
automatically.
[0417] Typically, the endoluminal images which were acquired using
the first data-acquisition device at the current location of the
second endoluminal data-acquisition device are displayed together
with endoluminal images that are being acquired in real time by the
second endoluminal data-acquisition device, while the second
endoluminal data-acquisition device is at the current location. For
some applications, endoluminal images that are acquired in real
time by the second endoluminal data-acquisition device, while the
second endoluminal data-acquisition device is at the current
location, are displayed together with an indication of the current
location of the second endoluminal data-acquisition device with
respect to an endoluminal image stack generated using endoluminal
images that were previously acquired by the first endoluminal
data-acquisition device. For some applications, using the
above-described technique, data acquired by first and second
endoluminal data acquisition devices are registered with respect to
one another, and the co-registered data are displayed subsequent to
termination of the acquisition of endoluminal images by both the
first and the second endoluminal data-acquisition devices. For some
applications, endoluminal images corresponding to the current
location of the second endoluminal data-acquisition device that
were acquired by the first endoluminal data acquisition device
and/or by the second endoluminal data acquisition device are
co-displayed with an indication of the current location of the
second endoluminal data-acquisition device on an extraluminal image
of the lumen, using the techniques described herein.
[0418] Reference is now made to FIG. 10, which shows the co-use of
previously-acquired IVUS images and a current, stabilized,
extraluminal fluoroscopic image stream, or with an angiogram image
from the native fluoroscopic image stream, in accordance with some
applications of the present invention. The native fluoroscopic
image stream is displayed in left side window 101. A region of
interest (ROI) 102 is marked, with a dotted white line, within left
side window 101. A stabilized image stream, generally based upon
ROI 102, is displayed in right side window 103. Vessel 104 is
highlighted, by means of contrast agent. Radiopaque markers 105 and
106 are mounted respectively at the proximal and distal ends of a
balloon carrying a stent. The balloon is being inserted through
vessel 104. The balloon, as shown, is being positioned in
preparation for the deployment of the stent at partial occlusion
107 which is at a narrower segment of vessel 104. An IVUS slice,
acquired prior to placement of the balloon with markers 105 and 106
into vessel 104, corresponding to the current location of distal
marker 106, is retrieved and displayed, typically in real time and
typically automatically, at the upper right corner of right side
window 103. FIG. 10 shows an illustrative IVUS slice 108 displayed
in the upper right corner of right side window 103. In accordance
with the applications described hereinabove, the IVUS slice that is
displayed is a slice that was acquired by an IVUS probe previously,
while the probe was inserted into the vessel under extraluminal
fluoroscopy. IVUS slice 108 depicts a healthy vessel location. The
display of slice 108 concurrently with positioning of the balloon,
in preparation for stent deployment, assists in confirming that the
distal end of the stent (corresponding to distal marker 106) is
properly positioned at a "healthy shoulder" of occlusion 107 (i.e.,
the point along the arterial lumen at which the occlusion is no
longer significant and/or the disease is no longer prevalent), as
is typically desired. For some applications, the display of the
corresponding IVUS slices is made relative to marker locations in a
single angiogram frame. For some applications, the display of the
corresponding IVUS slices is made relative to a three-dimensional
model that was generated from two (or more) two-dimensional gated
angiograms.
[0419] The cumulative effect of showing the extraluminal image
stream and IVUS slice 108 is as if the stent is being positioned
concurrently under both extraluminal fluoroscopic imaging and
endoluminal IVUS imaging. In practice, such concurrent imaging is
typically not possible because vessel 104 is too narrow to
accommodate both the IVUS catheter and the stent catheter, and also
because even if there were sufficient space, then the two catheters
may interfere with one another.
[0420] Reference is now made to FIG. 11, which shows the co-use of
previously-acquired IVUS images and a current, stabilized,
extraluminal fluoroscopic image stream, in accordance with some
applications of the present invention. Stack 111 comprises
previously-acquired IVUS slices previously acquired at locations
corresponding to the current locations of balloon markers 112 and
113. For some applications, the display of the corresponding IVUS
stack is made relative to marker locations in a static angiogram
frame.
[0421] Reference is now made to FIG. 12, which is a graph showing
the location along a lumen (e.g., along the center line of the
lumen) of an imaging head of an endoluminal imaging probe, versus
the frame numbers of the endoluminal image frames acquired by the
probe, during pullback of the probe. Typically, even during
automated pullback of the probe, the relative speed at which the
imaging head of the probe moves with respect to the lumen, and, in
some cases, the direction in which the imaging head moves with
respect to the lumen, varies over the course of the cardiac cycle,
due to pulsation of the lumen. As shown on portion 115 of the graph
(which typically corresponds to a systolic phase of the cardiac
cycle, or a portion thereof), in some cases, the imaging head of an
endoluminal imaging probe moves forward (i.e., distally) with
respect to the lumen during certain phases of the cardiac cycle,
even during pullback (pullback generally being in a distal to
proximal direction).
[0422] Still further typically, as a result of the imaging head
moving forward with respect to the lumen, in some cases, two or
more endoluminal image frames are acquired at a single location
along the lumen. For example, as shown in FIG. 12, frames x, y, and
z are acquired at a single location along the lumen. Frame x is
acquired pre-systole, while the probe is moving in a distal to
proximal direction with respect to the lumen, frame y is acquired
during systole, while the probe is moving in a proximal to distal
direction with respect to the lumen, and frame z is acquired
post-systole, while the probe is moving back past the same location
in a distal to proximal direction with respect to the lumen.
[0423] For some applications, manual pullback of the endoluminal
imaging probe is performed by an operator. In some cases, during
manual pullback, the operator pushes the probe forward at times in
order to view a given region for a second time. As a result, the
imaging probe typically acquires a plurality of endoluminal images
of given locations within the region. For example, a first image
may be acquired during the initial pullback past the location in
the distal to proximal direction, a second image may be acquired
when the probe is pushed forward by the operator in the proximal to
distal direction, and a third image may be acquired when the probe
is, subsequently, pulled back past the location in the distal to
proximal direction for a second time.
[0424] For some applications, forward motion of the endoluminal
imaging probe that is (a) due to pulsation of the lumen, and/or (b)
due to an operator of the probe pushing the probe forward, is
accounted for in order to facilitate co-registration of the
endoluminal images to an extraluminal image. Typically, in order to
facilitate co-registration, the system identifies redundant image
frames (i.e., image frames that are not required because they are
acquired at a location at which one or more additional image frames
are acquired), and rejects at least some of the redundant image
frames from being used for the co-registration, as described in
further detail hereinbelow.
[0425] For some applications, forward motion of the imaging probe
is detected by acquiring images of the imaging probe within the
lumen, and performing image processing on the angiographic images
in order to determine locations of the endoluminal image probe
marker with respect to the lumen at the time of the acquisition of
respective endoluminal image frames, e.g., in accordance with the
techniques described hereinabove.
[0426] For some applications, angiographic images of the imaging
probe within the lumen are acquired in the presence of contrast
agent (which makes the lumen visible in the angiographic images),
and the angiographic images are image processed in order to
determine locations of the endoluminal image probe marker with
respect to the lumen at the time of the acquisition of respective
endoluminal image frames. Typically, using image processing of
angiographic images of the probe within the lumen can be used to
identify forward motion of the imaging probe that is (a) due to
pulsation of the lumen, and (b) due to an operator of the probe
pushing the probe forward. This is because, in the angiographic
images, the system typically identifies a visible moving portion of
the endoluminal imaging probe (e.g., a radiopaque marker on the
imaging head). Using image processing, the system tracks the motion
of the visible, moving portion of the endoluminal probe with
respect to the lumen. Thus, motion of the visible, moving portion
of the imaging probe with respect to the lumen is identifiable in
the angiographic images, irrespective of the cause of the
motion.
[0427] For some applications, fluoroscopic images of the imaging
probe within the lumen are acquired in the absence of contrast
agent, and the fluoroscopic images are image processed in order to
determine locations of the endoluminal image probe marker with
respect to the lumen at the time of the acquisition of respective
endoluminal image frames. For some applications, as described
hereinabove, the location of a moving, visible portion of the
endoluminal imaging probe (e.g., a radiopaque marker on the imaging
head of the endoluminal imaging probe) is determined according to
its distance along a guide wire along which the imaging probe is
inserted, the distance typically being measured relative to the
distal tip of a guiding catheter through which the guidewire and
the imaging probe were previously inserted. For some applications,
the endoluminal imaging probe includes a portion that substantially
does not move with respect to the lumen during pullback, such as an
insertion sheath. The location of moving, visible portion of the
imaging probe is determined, via image processing, with reference
to the portion of the device that substantially does not move with
respect to the lumen during pullback. Typically, using image
processing of fluoroscopic images of the probe within the lumen can
be used to identify forward motion of the imaging probe that is due
to an operator of the probe pushing the probe forward. However,
image processing of fluoroscopic images of the probe inside the
lumen typically cannot be used to identify forward motion of the
imaging probe that is due to pulsation of the artery, since all of
the components of the probe (including the guidewire and the
insertion sheath, for example) move with respect to the lumen due
to pulsation of the lumen.
[0428] For some applications, forward motion of the endoluminal
probe that is caused by an operator pushing the probe forward is
determined using a longitudinal position/movement sensor coupled to
apparatus through which the endoluminal probe is inserted, e.g., as
described hereinabove with reference to FIG. 2.
[0429] In response to determining that two or more endoluminal
image frames correspond to the same location along the lumen due to
forward motion of the probe with respect to the lumen, at least one
of the image frames is not used for the co-display of the
endoluminal image frames with an extraluminal image of the lumen.
Typically, only the first endoluminal image frame that was acquired
at the location is used for the co-display of the endoluminal image
frames with an extraluminal image of the lumen. For some
applications, it is determined which at least one of the two or
more endoluminal image frames that correspond to the same location
along the lumen was acquired during forward motion of the probe,
and this frame is rejected from being used in the co-display.
Alternatively or additionally, another at least one of the two or
more endoluminal image frames that correspond to the same location
along the lumen is rejected from being used in the co-display.
[0430] For some applications, during pullback of the endoluminal
imaging device, the subject's ECG signal is detected. Respective
endoluminal images are identified as corresponding to the period in
the subject's cardiac cycle at the time when the image was
acquired, based upon the detected ECG signal (e.g., by indexing the
image frames with respect to the subject's ECG signal). For some
applications, based upon the identified correspondence, the system
determines which of the endoluminal images were acquired in a given
period of the subject's cardiac cycle, such as at least a portion
of systole, and these image frames are not used for the co-display
of the endoluminal image frames with an extraluminal image of the
lumen. For example, frames corresponding to at least a portion of
the subject's ECG signal between the S and T waves may be rejected
from being used in the co-display. Typically, associating
endoluminal image frames with phases of the subject's cardiac cycle
(e.g., by indexing with respect to the subject's ECG signal) can be
used to account for forward motion of the endoluminal imaging probe
that is caused by motion of the probe with respect to the lumen due
to pulsation of the lumen that is due to the subject's cardiac
cycle.
[0431] For some applications, techniques described herein are used
to account for the forward motion of the endoluminal imaging probe
in order to facilitate the generation of an endoluminal image
stack, the forward motion of the imaging probe typically being (a)
due to pulsation of the lumen, and/or (b) due to an operator of the
probe pushing the probe forward. Typically, in order to facilitate
generation of an endoluminal image stack, the system identifies
redundant image frames (i.e., image frames that are not required
because they are acquired at a location at which one or more
additional image frames are acquired), and rejects at least some of
the redundant image frames from being used in the endoluminal image
stack, as described in further detail hereinbelow. For some
applications, in response to determining that some of the image
frames were acquired during forward motion of the imaging probe,
the system places the image frames in order within the image stack,
and/or re-orders frames in an image stack that has already been
generated, such that the frames within the stack are placed in the
correct order. For some applications, the system indicates image
frames within an image stack that were acquired during forward
motion of the imaging probe, for example, by highlighting portions
of the image stack that were acquired during the forward
motion.
[0432] For some applications, forward motion of the imaging probe
is detected by acquiring angiographic images or fluoroscopic images
of the imaging probe within the lumen, and performing image
processing on the angiographic images in order to determine
locations of the endoluminal image probe marker with respect to the
lumen at the time of the acquisition of respective endoluminal
image frames, as described hereinabove. Typically, as described
hereinabove, image processing of angiographic images can be used to
identify forward motion of the imaging probe that is caused by (a)
pulsation of the lumen, and (b) an operator of the probe pushing
the probe forward. Further typically, image processing of
fluoroscopic images can only be used to identify forward motion of
the imaging probe that is caused by an operator of the probe
pushing the probe forward. For some applications, forward motion of
the endoluminal probe that is caused by an operator pushing the
probe forward is determined using a longitudinal position/movement
sensor coupled to apparatus through which the endoluminal probe is
inserted, e.g., as described hereinabove with reference to FIG.
2.
[0433] For some applications, during pullback of the endoluminal
imaging device, the subject's ECG signal is detected. Respective
endoluminal images are identified as corresponding to the period in
the subject's cardiac cycle at the time when the image was
acquired, based upon the detected ECG signal (e.g., by indexing the
image frames with respect to the subject's ECG signal). For some
applications, based upon the identified correspondence, the system
determines which of the endoluminal images were acquired in a given
period of the subject's cardiac cycle, such as at least a portion
of systole. Typically, associating endoluminal image frames with
phases of the subject's cardiac cycle (e.g., by indexing with
respect to the subject's ECG signal) can be used to account for
forward motion of the endoluminal imaging probe that is caused by
motion of the probe with respect to the lumen due to pulsation of
the lumen that is due to the subject's cardiac cycle.
[0434] For some applications, in order to generate the image stack
it is determined which image frames were acquired during forward
motion of the endoluminal imaging probe (e.g., based upon image
processing of angiographic or fluoroscopic images of the device
inside the lumen, or based upon associating the frames with
respective phases of the subject's cardiac cycle, such as, by
indexing the frames with respect to the subject's ECG signal), and,
in response thereto, those image frames are either rejected, or are
appropriately placed within the stack. For some applications, in
order to generate the image stack it is determined which locations
along the lumen have two or more endoluminal images corresponding
thereto, and, in response thereto, at least one of the image frames
corresponding to the location is rejected from being used in the
endoluminal image stack. Typically, only the first imaging frame to
have been acquired at each location along the lumen is used in the
image stack, and the other image frames acquired at the location
are rejected from being used in the image stack. Further typically,
it is determined which at least one of the two or more endoluminal
image frames that correspond to the same location along the lumen
were acquired during forward motion of the probe, and this frame is
rejected from being used in the image stack. Alternatively or
additionally, another at least one of the two or more endoluminal
image frames that correspond to the same location along the lumen
is rejected from being used in the image stack.
[0435] It is noted that some applications of the present invention
have been described with respect to an endoluminal image probe that
acquires image frames while moving generally in a distal to
proximal direction (i.e., during pullback of the imaging probe),
but that experiences some movement in a proximal to distal
direction. The scope of the present invention includes applying the
techniques described herein to an endoluminal image probe that
acquires image frames while moving generally in a proximal to
distal direction (i.e., while the probe is being pushed forward
through the lumen), but that experiences some movement in a distal
to proximal direction, mutatis mutandis.
[0436] For some applications, techniques described herein (e.g.,
techniques described with reference to FIG. 12) are performed by a
system that includes at least one processor, for use with an
endoluminal data-acquisition device that acquires a plurality of
endoluminal data points of a lumen of a body of a subject while
being moved through the lumen generally in a first direction with
respect to the lumen. For some applications, the processor includes
(a) duplicate-data-point-identification functionality configured to
determine that, at at least one location, two or more endoluminal
data points were acquired by the endoluminal data-acquisition
device, (b) data-point-selection functionality configured to
generate an output using a portion of the plurality of endoluminal
data points of the lumen acquired using the endoluminal
data-acquisition device, by using only a single data point
corresponding to the location, and (c) display-driving
functionality configured to drive a display to display the
output.
[0437] For some applications, the processor includes (a)
direction-determination functionality configured to determine that,
while acquiring at least one of the endoluminal data points, the
endoluminal data-acquisition device was moving in a second
direction that is opposite to the first direction, (b)
output-generation functionality configured, in response to the
determining, to generate an output using at least some of the
plurality of endoluminal data points of the lumen acquired using
the endoluminal data-acquisition device, and (c) display-driving
functionality configured to drive a display to display the
output.
[0438] For some applications, locations of an endoluminal imaging
probe associated with a first endoluminal modality (e.g., IVUS) are
identified as corresponding to respective endoluminal image frames
of the first imaging modality, in accordance with the techniques
described hereinabove. Subsequently, locations of an endoluminal
imaging probe associated with a second endoluminal modality (e.g.,
OCT) are identified as corresponding to respective endoluminal
image frames of the second imaging modality, in accordance with the
techniques described hereinabove. For example, forward motion of
one or both of the endoluminal imaging probes may be accounted for
in associating the locations of the endoluminal image probes with
the image frames, in accordance with techniques described
hereinabove. Consequently, the two data sets are co-registered to
one another. For some applications, the two endoluminal data sets
are displayed as overlaid or otherwise merged with one another.
[0439] For some applications, in order to determine the angular
orientation of the probe with respect to the lumen at the time of
the acquisition of respective endoluminal image frames, an
asymmetrically shaped radiopaque marker that is visible in
extraluminal images (e.g., angiographic or fluoroscopic images) of
the lumen is disposed on the imaging head of the endoluminal probe.
Alternatively or additionally, the marker may be disposed
asymmetrically with respect to the longitudinal axis of the imaging
head of the endoluminal probe. During the acquisition of
endoluminal image frames by the endoluminal imaging probe,
extraluminal images are acquired of the endoluminal image probe
within the lumen. Image processing is applied to the fluoroscopic
images in order to determine the angular orientation of the probe
with respect to the lumen at the time of the acquisition of
respective endoluminal image frames, typically automatically and
typically on-line, in accordance with techniques described
herein.
[0440] For some applications, the aforementioned techniques are
applied in order to account for unintentional rotation (typically,
roll) of the endoluminal imaging probe with respect to the lumen,
due to pulsation of the lumen, for example. For some applications,
the aformentioned techniques are applied in order to facilitate the
generation of an endoluminal image stack, in which the images that
comprise the stack are correctly rotationally aligned.
Alternatively or additionally, the aforementioned techniques are
applied to determine the orientation with respect to each other of
vessels that appear in the endoluminal images.
[0441] Reference is now made to FIG. 13 which shows image frames
120, 122, and 124 of a stent inside a blood vessel. Frame 120 is a
raw image frame of the stent inside the blood vessel.
[0442] For some applications, an enhanced extraluminal image, or
image sequence, of a deployed device and/or tool (for example, a
stent) is displayed. In accordance with respective applications,
the enhanced image of the deployed device is co-registered to an
endoluminal image (e.g., in accordance with the techniques
described herein), or is displayed independently of any endoluminal
images. For some applications, the enhancement is performed in
accordance with techniques described in US Patent Application
2010/0172556 to Cohen et al., which is incorporated herein by
reference.
[0443] For some applications, the image of the tool within the
stabilized image stream is enhanced in real time or near real time.
For some applications, enhancement of the image of the tool is
performed in combination with the techniques described in WO
08/107905 to Iddan, which is incorporated herein by reference.
[0444] For some applications, enhancement is performed
automatically upon frames that have been image-tracked such that
the tool is displayed in a same or similar relative location
throughout most or all frames, as described in US Patent
Application 2010/0172556 to Cohen, which is incorporated herein by
reference. For some applications, enhancement is performed by means
of temporal filtering of the image-tracked frames. Typically,
enhancement is performed in real time, or in near real time. Frame
122 of FIG. 13 is an enhanced image frame, generated in accordance
with techniques described in US Patent Application 2010/0172556 to
Cohen. It may be observed that stent 126 is more visible in frame
122 than in raw image frame 120.
[0445] For some applications, the temporal filtering applies a
weighted averaging function to the value of each pixel, as defined
by its relative locations in a series of consecutive frames, and
displays the resulting image. Alternatively or additionally, the
temporal filtering applies a median function to the value of each
pixel, as defined by its relative locations in a series of
consecutive frames, and displays the resulting image. Further
alternatively or additionally, the temporal filtering applies a
mode function to the value of each pixel, as defined by its
relative locations in a series of consecutive frames, and displays
the resulting image.
[0446] For some applications, in addition to the application of a
temporal filter, a spatial filter is applied to increase the
contrast in the enhanced image. For example, the spatial filter may
be a leveling filter. For some applications, contrast is increased
by histogram stretching, and/or by gamma correction.
[0447] In accordance with respective applications, contrast
enhancement is specifically applied to the edges of a tool, such as
a balloon, or to the struts of a tool, such as a stent.
[0448] For some applications, only the final image, representing
the outcome of the enhancement process, is displayed.
Alternatively, intermediate frames, reflecting gradual enhancement,
are also displayed on-line.
[0449] For some applications, enhancement is performed upon a
number of typically-consecutive gated image frames. When using
gated images, the enhancement is typically applied to fewer image
frames than when the enhancement is applied to non-gated image
frames, which may degrade the outcome of the enhancement process.
However, such gated frames are often already aligned to a
substantial extent, which may improve the outcome of the
enhancement process.
[0450] For some applications, alternative or additional techniques
are applied to enhance the visibility of the tool in an
extraluminal image or image stream, the techniques being performed
typically on-line, and typically automatically. For some
applications, the enhancement is performed by applying an iterative
algorithm on a set of images, the algorithm operating as follows.
An initial enhanced image is calculated from registered images,
typically by means of techniques disclosed hereinabove, such as
temporal filtering. In each iteration, the algorithm attempts to
improve the already-created enhanced image, by selecting only some
of the image frames to be used for creating a new enhanced image
frame, and not using the remaining image frames.
[0451] Typically, device contours are identified in at least some
of the image frames from which a recent enhanced image, or image
stream, was generated by the system (typically automatically, and
typically on-line) (a) identifying marker locations within the
image frame, (b) identifying curved edge lines in the vicinity of
markers, and (c) interpreting the edge lines as the device
contours. From among those image frames, a subset of the image
frames in which the device contours are most similar to each other
is selected, and other image frames are rejected. It is noted that
in accordance with this technique, some image frames are rejected
from the subset of image frames, even though edge lines
corresponding to the device contours appear in the rejected image
frames.
[0452] For some applications, the similarity of the device contours
in a set of image frames is determined based upon the similarity of
the shapes of the edge lines in the image frames. Alternatively or
additionally, the similarity of the device contours in a set of
image frames is determined by determining an extent to which the
edge lines are parallel to an imaginary line running from a first
(e.g., distal) marker to a second (e.g., proximal) marker in the
image frames.
[0453] Subsequent to the subset of image frames having been
selected, that subset is used for creating a new enhanced image,
again with the enhancement performed according to techniques
disclosed hereinabove. Typically, before averaging the subset of
image frames in order to create the new enhanced image frame, at
least some of the image frames in the subset are translated, such
that the edge lines in all of the image frames in the subset are
aligned with each other.
[0454] As described hereinabove, typically, in each step of the
iterative algorithm, the image frames in which the device contours
are the most similar to each other are selected. Alternatively, a
single image frame is selected as a baseline image frame, and image
frames are selected based upon a level of similarity of device
contours in the image frames to those of the baseline image
frame.
[0455] Typically, the above-described algorithm is applied
iteratively until no more image frames are excluded from the most
recent subset. Typically, the final outcome of applying the
iterative algorithm is an enhanced image frame in which at least
one of the device contour, or edges, or struts, or other device
elements, are more visible than they are in non-enhanced images
frames, or in enhanced image frames that have not had the above
iterative algorithm applied to them, ceteris paribus. Typically,
applying the iterative algorithm to image frames that have been
enhanced in accordance with techniques described in US 2010/0172556
to Cohen, which is incorporated herein by reference, further
enhances the image frames.
[0456] For example, the iterative enhancement may be used when
enhancing a stent previously deployed by a balloon carrying
radiopaque markers. The deflated balloon still resides,
intraluminally, within the deployed stent. Typically at this stage,
due to pulsation of the lumen, the balloon and the radiopaque
markers thereof shift (e.g., axially shift, and/or radially shift)
with respect to the endoluminal walls. The stent is fixated to the
endoluminal walls, and does not therefore shift with respect to the
endoluminal walls. Consequently, generating an enhanced image of
the stent from all image frames acquired along the cardiac cycle,
using a technique that relies upon using the locations of the
radiopaque markers (e.g., as described in US Patent Application
2010/0172556 to Cohen, which is incorporated herein by reference)
might suffer from a blurring effect resulting from the different
locations of the balloon markers, relative to the stent struts, in
some of those frames.
[0457] The application of the iterative enhancement algorithm
disclosed hereinabove, in which image frames are selected based
upon the similarity of contours in the image frames to the device
contours, typically reduces such a blurring effect. Thus, using the
above-described iterative enhancement algorithm for generating an
enhanced image frame (according to which, some image frames are
rejected from being used to generate the enhanced image frame) may
produce a better-enhanced image of the deployed stent than an
enhanced image frame that is generated using all the image frames
(or all of the gated image frames) irrespective of the similarity
of contours in the image frames to the device contours.
[0458] Frame 124 of FIG. 13 is an enhanced image frame, generated
in accordance with techniques described in US Patent Application
2010/0172556 to Cohen, and using the iterative algorithm, in
accordance with some applications of the present invention. It may
be observed that stent 126 is more visible in frame 124 than in raw
image frame 120, and in image frame 122, which was generated using
only techniques described in US Patent Application 2010/0172556 to
Cohen.
[0459] For some applications, an enhanced image stream is
displayed, by enhancing a plurality of image frames using
techniques described herein (e.g., using the above-described
iterative algorithm), and displaying the enhanced image frames as
an image stream.
[0460] For some applications, techniques described herein (e.g.,
techniques described with reference to FIG. 13) are performed by a
system that includes at least one processor. For some applications,
the processor includes image-receiving functionality configured to
receive the plurality of image frames into the processor, and
marker-identifying functionality configured to automatically
identify radiopaque markers in the image frames. Typically, the
processor further includes edge-line-identifying functionality
configured to automatically identify edge lines in a vicinity of
the radiopaque markers in the image frames, and image-selection
functionality configured, in response to the identifying of the
edge lines, to select a subset of the image frames that are based
upon the acquired image frames, based upon a level of similarity
between the edge lines in the selected image frames to one another.
For some applications, the processor includes image-alignment
functionality configured to align the edge lines in a plurality of
the selected image frames. Typically, the processor includes
image-averaging functionality configured to generate an averaged
image frame by averaging the plurality of aligned image frames, and
display-driving functionality configured to drive a display to
display the averaged image frame.
[0461] It is noted that although some techniques for co-using
extraluminal images and endoluminal data are described hereinabove
primarily with respect to extraluminal fluoroscopic/angiographic
images and endoluminal IVUS images, the scope of the present
invention includes applying the techniques described herein to
other forms of extraluminal and endoluminal images and/or data,
mutatis mutandis. For example, the extraluminal images may include
images generated by fluoroscopy, CT, MRI, ultrasound, PET, SPECT,
other extraluminal imaging techniques, or any combination thereof.
Endoluminal images may include images generated by optical
coherence tomography (OCT), near-infrared spectroscopy (NIRS),
intravascular ultrasound (IVUS), endobronchial ultrasound (EBUS),
magnetic resonance (MR), other endoluminal imaging techniques, or
any combination thereof. Endoluminal data may include data related
to pressure (e.g., fractional flow reserve), flow, temperature,
electrical activity, or any combination thereof. Examples of the
anatomical structure to which the aforementioned co-registration of
extraluminal and endoluminal images may be applied include a
coronary vessel, a coronary lesion, a vessel, a vascular lesion, a
lumen, a luminal lesion, and/or a valve. It is noted that the scope
of the present invention includes applying the techniques described
herein to lumens of a subject's body other than blood vessels (for
example, a lumen of the gastrointestinal or respiratory tract).
[0462] It will be appreciated by persons skilled in the art that
the present invention is not limited to what has been particularly
shown and described hereinabove. Rather, the scope of the present
invention includes both combinations and subcombinations of the
various features described hereinabove, as well as variations and
modifications thereof that are not in the prior art, which would
occur to persons skilled in the art upon reading the foregoing
description.
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