U.S. patent application number 14/143209 was filed with the patent office on 2014-04-24 for stabilized energy-delivery procedures.
This patent application is currently assigned to SYNC-RX, LTD.. The applicant listed for this patent is SYNC-RX, LTD.. Invention is credited to Gavriel IDDAN, David TOLKOWSKY.
Application Number | 20140114308 14/143209 |
Document ID | / |
Family ID | 39738904 |
Filed Date | 2014-04-24 |
United States Patent
Application |
20140114308 |
Kind Code |
A1 |
TOLKOWSKY; David ; et
al. |
April 24, 2014 |
STABILIZED ENERGY-DELIVERY PROCEDURES
Abstract
Apparatus and methods are described for use with a portion of a
subject's body that moves as a result of cyclic activity, including
sensing a phase of the cyclic activity. In a first cycle of the
activity, in response to sensing that the activity is at a given
phase, a therapeutic tool is actuated to apply a treatment to the
portion by applying energy to the portion. Following the given
phase in the first cycle and prior to an occurrence of the given
phase in a subsequent cycle, the tool is inhibited from applying
energy to the portion. In a second cycle of the activity,
subsequent to the inhibiting of the application of energy to the
portion, and in response to sensing that the second cycle is at the
given phase, the tool is actuated to apply energy to the portion.
Other applications are also described.
Inventors: |
TOLKOWSKY; David; (Tel Aviv,
IL) ; IDDAN; Gavriel; (Haifa, IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SYNC-RX, LTD. |
Netanya |
|
IL |
|
|
Assignee: |
SYNC-RX, LTD.
Netanya
IL
|
Family ID: |
39738904 |
Appl. No.: |
14/143209 |
Filed: |
December 30, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12075244 |
Mar 10, 2008 |
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14143209 |
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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: |
606/41 |
Current CPC
Class: |
A61B 2090/3762 20160201;
A61B 5/0036 20180801; A61F 2/958 20130101; A61B 2017/00694
20130101; A61B 8/0891 20130101; A61B 18/1492 20130101; A61B 2576/02
20130101; A61B 5/4836 20130101; A61B 6/5217 20130101; A61B 17/3207
20130101; A61B 2090/3782 20160201; A61M 5/007 20130101; A61B
5/02007 20130101; A61B 6/503 20130101; A61B 2017/00703 20130101;
A61M 2210/12 20130101; A61B 6/504 20130101; A61B 2017/00252
20130101; G16H 50/30 20180101; A61B 8/0883 20130101; A61B 6/541
20130101; A61B 8/543 20130101; A61B 6/12 20130101; A61B 90/37
20160201; A61B 5/7289 20130101; A61B 2017/22044 20130101; A61B
2090/3735 20160201; A61B 2017/22094 20130101 |
Class at
Publication: |
606/41 |
International
Class: |
A61B 18/14 20060101
A61B018/14 |
Claims
1. (canceled)
2. A method for use with a portion of a body of a subject that
moves as a result of cyclic activity of a body system of the
subject, the method comprising: sensing a phase of the cyclic
activity; in a first cycle of the cyclic activity, in response to
sensing that the cyclic activity is at a first given phase thereof,
actuating a therapeutic tool to apply a treatment to the portion of
the subject's body by applying energy to the portion of the
subject's body; following the given phase in the first cycle and
prior to an occurrence of the given phase in a subsequent cycle of
the cyclic activity, inhibiting the tool from applying energy to
the portion of the subject's body; and in a second cycle of the
cyclic activity, subsequent to the inhibiting of the application of
energy to the portion of the subject's body, and in response to
sensing that the second cycle of the cyclic activity is at the
given phase thereof, actuating the tool to apply energy to the
portion of the subject's body.
3. The method according to claim 2, further comprising: in a third
cycle that is between the first and second cycles, in response to
sensing that the cyclic activity is at the given phase thereof,
moving at least a portion of the tool, and following the given
phase in the third cycle, and prior to an occurrence of the given
phase in a further subsequent cycle of the cyclic activity,
inhibiting the portion of the tool from moving.
4. The method according to claim 2, further comprising: while
actuating the tool to apply energy to the portion of the subject's
body, acquiring a plurality of images of the tool inside the
portion of the subject's body; generating a stabilized image stream
by stabilizing the images with respect to the given phase of the
cyclic activity; and displaying the stabilized image stream.
5. The method according to claim 2, wherein the tool includes a
myocardial revascularization tool configured to sequentially apply
a revascularization treatment to respective treatment sites within
the portion of the subject's body, wherein actuating the tool to
apply energy to the portion of the subject's body comprises
actuating the tool to apply a revascularization treatment to a
treatment site, the method further comprising between successive
applications of energy to the portion of the subject's body, moving
at least a portion of the revascularization tool toward successive
treatment sites.
6. The method according to claim 5, wherein moving at least a
portion of the revascularization tool toward successive treatment
sites comprises moving the at least the portion of the tool such as
to create a defined pattern of treatment sites.
7. The method according to claim 2, wherein the tool includes an
ablation tool configured to sequentially ablate respective ablation
sites within the portion of the subject's body, wherein actuating
the tool to apply energy to the portion of the subject's body
comprises actuating the tool to ablate an ablation site, and the
method further comprising between successive applications of energy
to the portion of the subject's body, moving at least a portion of
the ablation tool toward successive ablation sites.
8. The method according to claim 7, wherein moving the at least the
portion of the tool comprises moving the at least the portion of
the tool such as to create a defined pattern of ablation sites.
9. The method according to claim 7, wherein moving the at least the
portion of the tool comprises moving the at least the portion of
the tool such as to apply a Maze procedure to the ablation
sites.
10. The method according to claim 7, wherein actuating the tool to
ablate the ablation site comprises actuating the tool to ablate the
ablation site using an ablation technique selected from the group
consisting of: laser ablation, electrocautery, RF ablation,
cryogenic ablation, and ultrasound ablation.
11. The method according to claim 7, wherein moving the at least
the portion of the tool comprises moving the at least the portion
of the tool such as to apply a pulmonary vein isolation technique
to a heart of the subject.
12. Apparatus for use with a portion of a body of a subject that
moves as a result of cyclic activity of a body system of the
subject, the apparatus comprising: a sensor for sensing a phase of
the cyclic activity; a therapeutic medical tool configured to apply
a treatment to the portion of the subject's by body by applying
energy to the portion of the subject's body; and an actuator
configured: in a first cycle of the cyclic activity in response to
the sensor sensing that the cyclic activity is at a first given
phase thereof, to actuate the tool to apply energy to the portion
of the subject's body, following the given phase in the first cycle
and prior to an occurrence of the given phase in a subsequent cycle
of the cyclic activity, to inhibit the tool from applying energy to
the portion of the subject's body, and in a second cycle of the
cyclic activity, subsequent to the inhibiting of the tool from
applying energy to the portion of the subject's body, and in
response to the sensor sensing that the second cycle of the cyclic
activity is at the given phase thereof, to actuate the tool to
apply energy to the portion of the subject's body.
13. The apparatus according to claim 12, wherein the actuator is
configured: in a third cycle that is between the first and second
cycles, in response to sensing that the cyclic activity is at the
given phase thereof, to move at least a portion of the tool, and
following the given phase in the third cycle, and prior to an
occurrence of the given phase in a further subsequent cycle of the
cyclic activity, to inhibit the portion of the tool from
moving.
14. The apparatus according to claim 12, further comprising: an
imaging device configured to acquire a plurality of images of the
tool inside the portion of the subject's body; and a display,
wherein the actuator is configured to generate a stabilized image
stream by stabilizing the images with respect to the given phase of
the cyclic activity; and to drive the display to display the
stabilized image stream.
15. The apparatus according to claim 12, wherein the tool comprises
a myocardial revascularization tool configured to sequentially
apply a revascularization treatment to respective treatment sites
within the portion of the subject's body, and wherein the actuator
is configured to: actuate the tool to apply a revascularization
treatment to a treatment site by actuating the tool to apply energy
to the portion of the subject's body, and between successive
applications of energy to the portion of the subject's body, to
move at least a portion of the revascularization tool toward
successive treatment sites.
16. The apparatus according to claim 15, wherein the actuator is
configured to move the tool such as to create a defined pattern of
treatment sites.
17. The apparatus according to claim 12, wherein the tool comprises
an ablation tool configured to sequentially ablate respective
ablation sites within the portion of the subject's body, and
wherein the actuator is configured to: actuate the tool to ablate
an ablation site by actuating the tool to apply energy to the
portion of the subject's body, and between successive applications
of energy to the portion of the subject's body, to move at least a
portion of the ablation tool toward successive ablation sites.
18. The apparatus according to claim 17, wherein the ablation tool
is configured to ablate the ablation sites using an ablation
technique selected from the group consisting of: laser ablation,
electrocautery, RF ablation, cryogenic ablation, and ultrasound
ablation.
19. The apparatus according to claim 17, wherein the actuator is
configured to move the at least the portion of the tool by moving
the at least the portion of the tool to such as create a defined
pattern of ablation sites.
20. The apparatus according to claim 17, wherein the actuator is
configured to apply a Maze procedure to the ablation sites by
moving the at least the portion of the tool toward successive
ablation sites.
21. The apparatus according to claim 17, wherein the ablation tool
is configured to apply a pulmonary vein isolation technique to a
heart of the subject by applying energy to successive ablation
sites.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] The present patent application is a continuation of U.S.
Ser. No. 12/075,244 to Tolkowsky et al. (published as US
2008/0221442), filed Mar. 10, 2008, which claims the benefit of
U.S. Provisional Patent Application No. 60/906,091 filed on Mar. 8,
2007, 60/924,609 filed on May 22, 2007, 60/929,165 filed on Jun.
15, 2007, 60/935,914 filed on Sep. 6, 2007, and 60/996,746 filed on
Dec. 4, 2007, all named "Apparatuses and methods for performing
medical procedures on cyclically-moving body organs," all of which
applications are incorporated herein by reference.
[0002] The present application is related to the following
applications, which are incorporated herein by reference: [0003]
U.S. patent application Ser. No. 12/075,214, entitled "Tools for
use with moving organs," to Iddan et al. (published as US
2008/0221439), filed Mar. 10, 2008. [0004] U.S. patent application
Ser. No. 12/075,252, entitled "Imaging and tools for use with
moving organs," to Iddan et al. (published as US 2008/0221440),
filed Mar. 10, 2008. [0005] PCT Application PCT/IL2008/000316,
entitled "Imaging and tools for use with moving organs," to Iddan
et al. (published as WO 08/107,905), filed on Mar. 9, 2008.
FIELD OF THE INVENTION
[0006] The present invention generally relates to medical
apparatus. Specifically, the present invention relates to
stabilizing imaging of cyclically moving body portions.
BACKGROUND OF THE INVENTION
[0007] Continuous images of a cyclically-moving body organ are
typically displayed in the course of many medical procedures such
as procedures performed on the heart, the thorax, the respiratory
tract, the eyes, or the cardiovascular system. Such images
typically shift constantly and are also prone to blurring.
Consequently, such images are typically difficult to observe, and
are difficult to use in making clinical decisions over an extended
period of time (such as the entire duration of the procedure).
[0008] Many procedures are performed with respect to moving body
parts, for example the insertion of balloons and stents into moving
blood vessels. A difficulty associated with such procedures is the
targeted deployment and/or actuation of tools with respect to the
moving body part.
[0009] U.S. Pat. No. 4,865,043 to Shimoni, which is incorporated
herein by reference, describes a data selection method and system
using a plurality of multi-dimensional windows wherein two
parameters of ECG signals are tested for determining whether the
imaging data received simultaneously with the ECG signal is to be
accepted. The plurality of windows are described as providing a
capability to gate and to sort imaging data based on the passage of
associated ECG signals through each of the plurality of windows
with different parameters. Thus images are described as being
reconstructed for a population of abnormally short or long heart
cycles from a common data pool.
[0010] U.S. Pat. No. 3,954,098 to Dick et al., which is
incorporated herein by reference, describes a scan converter
storage surface which is divided into image spaces corresponding to
different points in the heart cycle. Ultrasound echoes from heart
structures are plotted in the image spaces by means of special x, y
sweeps which are offset to the image spaces by timing
circuitry.
[0011] U.S. Pat. No. 4,382,184 to Wernikoff, which is incorporated
herein by reference, describes X-ray apparatus and methods for
producing discrete images of a human organ in fluctuating motion,
e.g., the heart and related vessels. Each image is derived at a
selected time related to the cardiac cycle. The images are
independently presented on respective discrete areas within a
common image plane. A source of X-rays irradiates the organ. A
physiological synchronizer produces timing signals within the
cardiac cycle for controlling the periods of transmission of the
X-ray beam through the organ during, for example, end diastole and
end systole. An anti-scattering, masking frame has alternate
parallel slits and bars at equal intervals exposing substantially
half the area of presentation of an X-ray sensitive film in
alternate, equally spaced area strips during, e.g., diastole. The
frame is repositioned in response to a signal from the synchronizer
for actuating it relative to the film, such that the bars then
cover the sensitized areas of the film and expose substantially the
remaining half of the film during systole. The image elements are
interdigitally juxtaposed to present the diastolic and systolic
images in an interlaced pattern. Relative displacements of the
organ during a cardiac cycle may be determined from the juxtaposed
image elements.
[0012] U.S. Pat. No. 4,016,871 to Schiff, which is incorporated
herein by reference, describes a system which is capable of
simultaneously displaying a plurality of waveforms on the face of a
CRT which are representative of ECG, arterial pressures and
operating states of the mechanical heart assistance devices, as
well as a "timing bar" which sweeps across the CRT face in
synchronism with the ECG trace, for example. Optical pickups are
slidably mounted adjacent the CRT face across the path of the
"timing bar" sweep for activating photodetectors which in turn
initiate inflation and deflation of mechanical assistive devices at
any desired point along the ECG or pressure trace. Any one of the
pressure or ECG traces may be "frozen" on the display face to
facilitate comparison between a trace of the condition of the heart
prior to the use of heart assistance and a trace of the augmented
condition. All traces may be freely moved to any location upon the
display face so as to permit close positioning and even
superimposition of two or more traces to still further facilitate
visual comparisons. The timing bar may also be utilized to provide
an electrical pacing assist for controlling patient heart rate as
well as for extending the heart refractory period enabling the
assistance devices to operate at reduced rates.
[0013] U.S. Pat. No. 3,871,360 to Van Horn et al., which is
incorporated herein by reference, describes a system for timing
biological imaging, measuring, or therapeutic apparatus in
accordance with selected physiological states of a subject,
featuring in various aspects generation of respiratory windows on
the basis of processed electrical signals derived from prior
respiration history, digital offset correction circuitry for the
respiratory signals, and generation of cardiac timing signals on
the basis of prior cardiac cycle history.
[0014] U.S. Pat. No. 4,031,884 to Henzel, which is incorporated
herein by reference, describes apparatus for correlating the
respiratory and cardiac cycles includes a circuit for defining a
chosen period in the progress of the respiratory cycle as the end
of a regulatable delay beginning when the ascending front of the
inspiratorial pressure reaches a regulatable level as well as a
circuit for defining a chosen period in the progress of the cardiac
cycle as the end of a regulatable delay beginning when the
differential dV/dt of the blood pressure reaches a regulatable
level. An operator such as a terminal relay is activated upon the
coincidence of these two periods in time after a regulatable delay
and during a regulatable period.
[0015] U.S. Pat. No. 4,994,965 to Crawford et al., which is
incorporated herein by reference, describes a method of reducing
image artifacts in tomographic, projection imaging systems due to
periodic motion of the object being imaged, and includes the
acquisition of a signal indicative of the periodic motion. This
signal is used to identify a quiescent period in the periodic
motion so that the acquisition of projection data may be
coordinated to be centered within the quiescent period.
[0016] U.S. Pat. No. 4,878,115 to Elion, which is incorporated
herein by reference, describes a method in which a dynamic coronary
roadmap of the coronary artery system is produced by recording and
storing a visual image of the heart creating a mask sequence,
recording and storing another dynamic visual image of the heart
after injection of a contrast medium thereby creating a contrast
sequence, matching the different durations of two sequences and
subtracting the contrast sequence from the mask sequence producing
a roadmap sequence. The roadmap sequence is then replayed and added
to live fluoroscopic images of the beating heart. Replay of the
roadmap sequence is triggered by receipt of an ECG R-wave. The
result is described as a dynamically moving coronary roadmap image
which moves in precise synchronization with the live incoming
fluoroscopic image of the beating heart.
[0017] U.S. Pat. No. 4,709,385 to Pfeiler, which is incorporated
herein by reference, describes an x-ray diagnostics installation
for subtraction angiography, which has an image memory connected to
an output of an x-ray image intensifier video chain which has a
number of addresses for storing individual x-ray video signals
obtained during a dynamic body cycle of a patient under
observation. A differencing unit receives stored signals from the
image memory as well as current video signals and subtracts those
signals to form a superimposed image. Entry and readout of signals
to and from the image memory is under the command of a control unit
which is connected to the patient through, for example, an EKG
circuit for identifying selected occurrences in the body cycle
under observation. Entry and readout of data from the image memory
is thereby controlled in synchronization with the selected
occurrences in the cycle.
[0018] U.S. Pat. No. 4,270,143 to Morris, which is incorporated
herein by reference, describes a cross-correlation video tracker
and method for automatically tracking a relatively moving scene by
storing elements from a frame of a video signal to establish a
reference frame and comparing elements from a subsequent frame with
the stored reference frame to derive signals indicating the
direction and angular distance of scene relative movement. A
cross-correlation difference signal is generated which represents
the difference between a pair of cross-correlation signals
dependent on the correlations of the subsequent frame elements and
the stored reference elements at two predetermined opposite
relative shifts. A circuit is responsive to this difference signal
for generating an error signal indicative of the amount of shift
required to center the stored reference frame with respect to the
subsequent frame.
[0019] U.S. Pat. No. 4,758,223 to Rydell, which is incorporated
herein by reference, describes a hand-operated device for inflating
the expander on a balloon-type catheter and for perfusing fluids
through the catheter and out its distal end.
[0020] U.S. Pat. No. 4,723,938 to Goodin et al., which is
incorporated herein by reference, describes an inflation/deflation
device for an angioplasty balloon catheter which permits quick
inflation to an approximate working pressure followed by a fine but
slower adjustment to a final desired pressure.
[0021] U.S. Pat. No. 6,937,696 to Mostafavi, which is incorporated
herein by reference, describes a method and system for
physiological gating. A method and system for detecting and
estimating regular cycles of physiological activity or movements is
also disclosed. Another disclosed embodiment is directed to
predictive actuation of gating system components. Yet another
disclosed embodiment is directed to physiological gating of
radiation treatment based upon the phase of the physiological
activity. Gating can be performed, either prospectively or
retrospectively, to any type of procedure, including radiation
therapy or imaging, or to other types of medical devices and
procedures such as PET, MRI, SPECT, and CT scans.
[0022] U.S. Pat. No. 6,246,898 to Vesely et al., which is
incorporated herein by reference, describes a method for carrying
out a medical procedure using a 3-D tracking and imaging system. A
surgical instrument, such as a catheter, probe, sensor, pacemaker
lead, needle, or the like is inserted into a living being, and the
position of the surgical instrument is tracked as it moves through
a medium in a bodily structure. The location of the surgical
instrument relative to its immediate surroundings is displayed to
improve a physician's ability to precisely position the surgical
instrument. The medical procedures including targeted drug
delivery, sewing sutures, removal of an obstruction from the
circulatory system, a biopsy, amniocentesis, brain surgery,
measurement of cervical dilation, evaluation of knee stability,
assessment of myocardial contractibility, eye surgery, prostate
surgery, trans-myocardial revascularization (TMR), robotic surgery,
and evaluation of RF transmissions.
[0023] US Patent Application Publication 2006/0058647 to Strommer
et al., which is incorporated herein by reference, describes a
method for delivering a medical device coupled with a catheter, to
a selected position within a lumen of the body of a patient, the
method comprising the procedures of: registering a
three-dimensional coordinate system with a two-dimensional
coordinate system, the three-dimensional coordinate system being
associated with a medical positioning system (MPS), the
two-dimensional coordinate system being associated with a
two-dimensional image of the lumen, the two-dimensional image being
further associated with an organ timing signal of an organ of the
patient; acquiring MPS data respective of a plurality of points
within the lumen, each of the points being associated with the
three-dimensional coordinate system, each of the points being
further associated with a respective activity state of the organ;
determining a temporal three-dimensional trajectory representation
for each of the respective activity states from the acquired MPS
data which is associated with the respective activity state;
superimposing the temporal three-dimensional trajectory
representations on the two-dimensional image, according to the
respective activity state; receiving position data respective of
the selected position, by selecting at least one of the points
along the temporal three-dimensional trajectory representation;
determining the coordinates of the selected position in the
three-dimensional coordinate system, from the selected at least one
point; determining the current position of the medical device in
the three-dimensional coordinate system, according to an output of
an MPS sensor attached to the catheter in the vicinity of the
medical device; maneuvering the medical device through the lumen,
toward the selected position, according to the current position
relative to the selected position; and producing a notification
output when the current position substantially matches the selected
position.
[0024] U.S. Pat. No. 6,666,863 to Wentzel et al., which is
incorporated herein by reference, describes devices and methods for
performing percutaneous myocardial revascularization (PMR). An
embodiment is described in which a detector of an ablation
controller provides a detect signal when a sensor block output
signal indicates that a first electrode is touching the wall of the
heart. The ablation controller may also provide a detect signal
when the heart is in a less vulnerable portion of the cardiac
rhythm, such as when the ventricles of the heart are contracting.
As such, the ablation controller is described as helping to
identify when the first electrode is in contact with the wall of
the heart, thereby reducing the likelihood that an ablation will be
triggered when the first electrode is not in contact with the
endocardium of the heart and cause damage to the blood platelets
within the heart.
[0025] U.S. Pat. No. 5,176,619 to Segalowitz, which is incorporated
herein by reference, describes a heart-assist device which includes
a flexible catheter carrying at least a ventricular balloon, such
balloon corresponding in size and shape to the size and shape of
the left ventricle in the heart being assisted, the ventricular
balloon being progressively inflated creating a wave-like pushing
effect and deflated synchronously and automatically by means of a
control console which responds to heart signals from the catheter
or elsewhere.
[0026] PCT Publication WO 94/010904 to Nardella, which is
incorporated herein by reference, describes an ablation catheter
that has an ablation electrode at a distal end coupled to an
ablation power source through a low impedance coupling. In some
embodiments, ablation only occurs while the heart is in a desired
part of the cardiac cycle, the ablation power intervals being
triggered by timing pulses synchronized with detection of the R
wave. This mode of actuation is described as assuring that the
heart is essentially stationary before delivery of ablation energy,
thus minimizing the risk of inadvertently ablating healthy
tissue.
[0027] An article by Boyle et al., entitled "Assessment of a Novel
Angiographic Image Stabilization System for Percutaneous Coronary
Intervention" (Journal of Interventional Cardiology," Vol. 20 No.
2, 2007), which is incorporated herein by reference, describes a
system for stabilizing angiographic images at a region of interest
in order to assist during percutaneous coronary intervention
(PCI).
[0028] An article by Timinger et al., entitled "Motion compensated
coronary interventional navigation by means of diaphragm tracking
and elastic motion models" (Phys Med Biol. 2005 Feb. 7;
50(3):491-503), which is incorporated herein by reference, presents
a method for compensating the location of an interventional device
measured by a magnetic tracking system for organ motion and thus
registering it dynamically to a 3D virtual roadmap. The motion
compensation is accomplished by using an elastic motion model which
is driven by the ECG signal and a respiratory sensor signal derived
from ultrasonic diaphragm tracking.
[0029] An article by Timinger et al., entitled "Motion compensation
for interventional navigation on 3D static roadmaps based on an
affine model and gating" (Phys Med Biol. 2004 Mar. 7;
49(5):719-32), which is incorporated herein by reference, describes
a method for enabling cardiac interventional navigation on
motion-compensated 3D static roadmaps.
[0030] An article by Turski et al., entitled "Digital Subtraction
Angiography `Road Map`" (American Journal of Roentgenology, 1982),
which is incorporated herein by reference, describes a technique
called roadmapping. An arterial roadmap for the subsequent
manipulation of catheters under fluoroscopy is generated by means
of first injecting a contrast agent into said arteries and using
the resulting, "highlighted" arterial image as a background to the
real-time fluoroscopic imaging of the catheterization
procedure.
[0031] An article by Iddan et al., entitled "3D imaging in the
studio and elsewhere" (SPIE Proceedings Vol. 4298 2001), which is
incorporated herein by reference, describes the technique of
background subtraction and replacement of video images, which has
been used in TV studios.
[0032] The following patents and patent applications, which are
incorporated herein by reference, may be of interest: [0033] U.S.
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SUMMARY OF THE INVENTION
[0099] In some embodiments of the invention, apparatus and methods
are used for facilitating medical procedures performed on
cyclically-moving organs, so that such procedures are performed
under a partial or full virtual stabilization of such organs. In
some embodiments, the stabilization comprises at least one of the
following elements: the stabilization of image(s) being viewed with
respect to the motion of an organ, and the actuation of tool(s)
applied to the organ in synchronization with the organ's
motion.
[0100] In some embodiments, continuously-generated image frames of
cyclically-moving organs are gated to one or more physiological
signals or processes, wherein the cycle(s) of such signals or
processes correspond to a motion cycle of the organ being imaged.
Consequently, the displayed gated image frames of the organ are
typically all in a selected same phase of a motion cycle of the
organ.
[0101] In some embodiments, the gated images are displayed with a
smoothened transition filling the gaps among them, generating a
synthesized, continuous video stream.
[0102] In some embodiments, image tracking is applied to
continuously-generated images of moving organs, to align such
images to one another. The motion to which such tracking is applied
may be cyclical, or non-cyclical, or a combination of both. The
visual effect of such motion is typically reduced by the image
tracking.
[0103] In some embodiments, a combination of the aforementioned
gating, tracking and/or gap filling are applied to generate a
stabilized image stream.
[0104] In some embodiments, road mapping is applied to the
stabilized image stream. In some embodiments, roadmapping is
applied to the stabilized image stream to facilitate a medical
procedure that is performed on the moving organ.
[0105] In some embodiments, the actuation or movement of one or
more medical tools applied to a cyclically-moving organ is
synchronized with one or more physiological signals or processes
whose cycle(s) corresponds to a motion cycle of the organ.
Consequently, the tool is typically actuated only during one or
more selected same phases in a motion cycle of the organ. In some
embodiments, the synchronized actuation of medical tools controls
the application of linear motion, angular motion, energy, substance
delivery, or any combination thereof.
[0106] In some embodiments, the aforementioned stabilized imaging
and synchronized tool application are applied jointly to a
cyclically moving organ. In some embodiments, images of the organ
are stabilized with respect to a given phase of the cycle, and the
actuation of the tool is synchronized to the same phase. In some
embodiments, this leads to virtual stabilization of the
cyclically-moving organ, both with respect to the imaging of the
organ and the tools being moved and/or applied.
[0107] It is noted, however, that the scope of the present
invention includes synchronized tool application and/or movement
with respect to a cyclically moving organ, using techniques
described herein, even in the absence of stabilized imaging as
described herein, or even in the absence of any imaging.
[0108] In some embodiments, the aforementioned techniques are
applied to an organ that may not be cyclically moving, but is
cyclically active, for example, an organ that undergoes neural
cyclic activity.
[0109] There is therefore provided, in accordance with an
embodiment of the invention, apparatus for imaging a portion of a
body of a subject that moves as a result of cyclic activity of a
first body system of the subject and that also undergoes additional
motion, the apparatus including:
[0110] an imaging device for acquiring a plurality of image frames
of the portion of the subject's body;
[0111] a sensor for sensing a phase of the cyclic activity of the
first body system;
[0112] a control unit configured to generate a stabilized set of
image frames of the portion of the subject's body: [0113] by
identifying a given phase of the cyclic activity of the first body
system, and outputting a set of the image frames corresponding to
image frames of the portion acquired during the given phase, and
[0114] by image tracking at least the set of image frames to reduce
imaged motion of the portion of the subject's body associated with
the additional motion; and
[0115] a display configured to display the stabilized set of image
frames of the portion of the subject's body.
[0116] In an embodiment, the control unit is configured to identify
the given phase of the cyclic activity using a gating signal, and
the display is configured to display a representation of the gating
signal simultaneously with displaying the stabilized set of image
frames.
[0117] In an embodiment, the display is configured to display an
enlarged stabilized set of image frames of a region within the
portion of the subject's body.
[0118] In an embodiment, to generate the stabilized set of image
frames of the portion of the subject's body, the control unit is
configured:
[0119] to identify a first image frame acquired during the given
phase,
[0120] subsequently, to image track the first identified image
frame,
[0121] subsequently, to identify a second image frame acquired
during the given phase, and
[0122] subsequently, to image track the second identified image
frame.
[0123] In an embodiment, to generate the stabilized set of image
frames of the portion of the subject's body, the control unit is
configured:
[0124] to image track a first image frame,
[0125] subsequently, to place the first image tracked frame in the
stabilized set of image frames if the first image tracked frame was
acquired during the given phase,
[0126] subsequently to image track a second image frame, and
[0127] subsequently, to place the second image tracked frame in the
stabilized set of image frames if the second image tracked frame
was acquired during the given phase.
[0128] In an embodiment, to generate the stabilized set of image
frames of the portion of the subject's body, the control unit is
configured:
[0129] to generate a gated set of image frames of the plurality of
image frames corresponding to image frames of the portion acquired
during the given phase, and
[0130] subsequently, to image track the gated set of image
frames.
[0131] In an embodiment, to generate the stabilized set of image
frames of the portion of the subject's body, the control unit is
configured:
[0132] to image track the plurality of image frames of the portion
of the subject's body, and
[0133] subsequently, to generate a set of image frames
corresponding to those of the tracked image frames of the portion
that were acquired during the given phase.
[0134] In an embodiment, the control unit includes a video tracker
selected from the group consisting of: an edge tracker, a centroid
tracker, a correlation tracker, and an object tracker, and the
control unit is configured to image track the at least the set of
image frames using the selected video tracker.
[0135] In an embodiment, the control unit is configured to generate
the set of image frames corresponding to image frames of the
portion acquired during the given phase by controlling the imaging
device to acquire the plurality of image frames only when the
cyclic activity is at the given phase.
[0136] In an embodiment,
[0137] the imaging device is configured to acquire the plurality of
image frames throughout the cyclic activity, and
[0138] the control unit is configured to generate the set of image
frames corresponding to image frames of the portion acquired during
the given phase, by selecting image frames corresponding to image
frames of the portion acquired during the given phase from the
plurality of image frames.
[0139] In an embodiment, the apparatus further includes a user
interface, and the control unit is configured to receive an input
from a user, via the user interface, and to select a phase of the
cyclic activity as being the given phase in response to the
input.
[0140] In an embodiment, the display is configured to display the
plurality of acquired image frames simultaneously with displaying
the stabilized set of image frames.
[0141] In an embodiment, the apparatus is configured for the
display to display the stabilized set of image frames in real time
with respect to the acquisition of the plurality of image frames by
the imaging device.
[0142] In an embodiment, the apparatus is configured for the
display to display the stabilized set of image frames within 4
seconds of the imaging device having imaged the plurality of image
frames.
[0143] In an embodiment, the apparatus is configured for the
display to display the stabilized set of image frames less than two
cycles of the cyclic activity after the imaging device imaged the
plurality of image frames.
[0144] In an embodiment, the apparatus is configured for the
display to display the stabilized set of image frames during a
medical procedure during which the imaging device images the
plurality of image frames.
[0145] In an embodiment, the apparatus is configured to display the
stabilized set of image frames subsequent to a medical procedure
during which the imaging device imaged the plurality of image
frames.
[0146] In an embodiment, the apparatus further includes a data
storage unit configured to store the stabilized set of image
frames.
[0147] In an embodiment, the control unit is configured to enhance
the stabilized set of image frames by image processing the
stabilized set of image frames.
[0148] In an embodiment, the additional motion is not associated
with cyclic activity of the subject's body, and the control unit is
configured to reduce the imaged motion associated with the
additional motion that is not associated with cyclic activity, by
image tracking at least the set of image frames.
[0149] In an embodiment, the additional motion is associated with
whole-body motion of the subject, and the control unit is
configured to reduce the imaged motion associated with the
whole-body motion by image tracking at least the set of image
frames.
[0150] In an embodiment, the apparatus further includes:
[0151] a contrast agent; and
[0152] an injection tool configured to inject the contrast agent
into a space within the portion of the subject's body, and [0153]
the imaging device is configured to acquire at least one image
frame of the space during the given phase, at a time when at least
some of the contrast agent is present within the space, and [0154]
the display is configured to display the at least one image frame
of the space overlaid on at least one same one of the stabilized
set of image frames.
[0155] In an embodiment,
[0156] the imaging device is configured to acquire a first image
frame of the space during the given phase of a first cycle of the
cyclic activity, at a time when at least some of the contrast agent
is present within the space,
[0157] the imaging device is configured to acquire a second image
frame of the space during the given phase of a second cycle of the
cyclic activity, at a time when at least some of the contrast agent
is present within the space, and
[0158] the display is configured to display the first and the
second image frame of the space overlaid on at least one same frame
of the stabilized set of image frames.
[0159] In an embodiment,
[0160] the space includes a lumen containing an occlusion,
[0161] the injection tool is configured to inject the contrast
agent into the lumen on a proximal side of the occlusion and on a
distal side of the occlusion,
[0162] the imaging device is configured to acquire at least one
image frame of the lumen on the proximal side of the occlusion
during the given phase of a cycle of the cyclic activity, at a time
when at least some of the contrast agent is present within the
lumen on the proximal side of the occlusion,
[0163] the imaging device is configured to acquire at least one
image frame of the lumen on the distal side of the occlusion during
the given phase of the cycle, at a time when at least some of the
contrast agent is present within the lumen on the distal side of
the occlusion, and
[0164] the display is configured to display the at least one image
frame of the lumen on the proximal side of the occlusion and the at
least one image frame of the lumen on the distal side of the
occlusion overlaid on at least one same frame of the stabilized set
of image frames.
[0165] In an embodiment,
[0166] the space includes a lumen containing an occlusion,
[0167] the injection tool is configured to inject the contrast
agent into the lumen on a proximal side of the occlusion and on a
distal side of the occlusion,
[0168] the imaging device is configured to acquire at least one
image frame of the lumen on the proximal side of the occlusion
during the given phase of a first cycle of the cyclic activity, at
a time when at least some of the contrast agent is present within
the lumen on the proximal side of the occlusion,
[0169] the imaging device is configured to acquire at least one
image frame of the lumen on the distal side of the occlusion during
the given phase of a second cycle of the cyclic activity, at a time
when at least some of the contrast agent is present within the
lumen on the distal side of the occlusion, and
[0170] the display is configured to display the at least one image
frame of the lumen on the proximal side of the occlusion and the at
least one image frame of the lumen on the distal side of the
occlusion overlaid on at least one same frame of the stabilized set
of image frames.
[0171] In an embodiment,
[0172] the space includes a lumen containing an occlusion,
[0173] the injection tool is configured to inject the contrast
agent into the lumen on a proximal side of the occlusion,
[0174] the apparatus further includes a second injection tool
configured to inject the contrast agent into the lumen on a distal
side of the occlusion,
[0175] the imaging device is configured to acquire at least one
image frame of the lumen on the proximal side of the occlusion
during the given phase of a cycle of the cyclic activity, at a time
when at least some of the contrast agent is present within the
lumen on the proximal side of the occlusion,
[0176] the imaging device is configured to acquire at least one
image frame of the lumen on the distal side of the occlusion during
the given phase of the cycle, at a time when at least some of the
contrast agent is present within the lumen on the distal side of
the occlusion, and
[0177] the display is configured to display the at least one image
frame of the lumen on the proximal side of the occlusion and the at
least one image frame of the lumen on the distal side of the
occlusion overlaid on at least one same frame of the stabilized set
of image frames.
[0178] In an embodiment,
[0179] the space includes a lumen containing an occlusion,
[0180] the injection tool is configured to inject the contrast
agent into the lumen on a proximal side of the occlusion,
[0181] the apparatus further includes a second injection tool
configured to inject the contrast agent into the lumen on a distal
side of the occlusion,
[0182] the imaging device is configured to acquire at least one
image frame of the lumen on the proximal side of the occlusion
during the given phase of a first cycle of the cyclic activity, at
a time when at least some of the contrast agent is present within
the lumen on the proximal side of the occlusion,
[0183] the imaging device is configured to acquire at least one
image frame of the lumen on the distal side of the occlusion during
the given phase of a second cycle of the cyclic activity, at a time
when at least some of the contrast agent is present within the
lumen on the distal side of the occlusion, and [0184] the display
is configured to display the at least one image frame of the lumen
on the proximal side of the occlusion and the at least one image
frame of the lumen on the distal side of the occlusion overlaid on
at least one same frame of the stabilized set of image frames.
[0185] In an embodiment, the imaging device includes a
fluoroscope.
[0186] In an embodiment, the space includes a space selected from
the group consisting of a chamber of a heart of the subject, a
lumen of a coronary blood vessel of the subject, and a lumen of an
aorta of the subject, and the injection tool is configured to
inject the contrast agent into the selected space.
[0187] In an embodiment, the control unit is configured to
construct at least one three-dimensional image frame of the space,
during the given phase, based on image frames acquired at the time
when at least some of the contrast agent is present within the
space.
[0188] In an embodiment, the apparatus further includes a medical
tool configured to be inserted into the space, the apparatus is
configured to acquire an image of the tool while the tool is inside
the space, and the display is configured to display the image of
the tool overlaid on the image frame of the space.
[0189] In an embodiment, the control unit is configured to identify
when the injection tool injects the contrast agent by image
processing a set of image frames of the space.
[0190] In an embodiment, the control unit is configured to identify
when the injection tool injects the contrast agent by specifically
analyzing a region of at least some of the plurality of image
frames that corresponds to a vicinity of a distal tip of the
injection tool.
[0191] In an embodiment, the control unit is configured to identify
when the injection tool injects the contrast agent by determining a
level of darkness of the region of at least some of the plurality
of image frames that corresponds to the vicinity of the distal tip
of the injection tool.
[0192] In an embodiment, the apparatus further includes a user
interface, and the display is configured to receive an input from a
user, via the user interface, and to display a marking at a given
position within the portion of the subject's body within the
stabilized set of image frames, in response to the input.
[0193] In an embodiment, the display is configured to display two
or more views of the stabilized set of image frames of the portion
of the subject's body, and to display the marking at the given
position within respective views of the stabilized set of image
frames.
[0194] In an embodiment, the imaging device is further configured
to image a plurality of images of a medical tool disposed within
the portion of the subject's body, and the control unit is
configured to generate a stabilized set of image frames of the
medical tool.
[0195] In an embodiment, the medical tool includes a medical tool
that is implanted within the portion of the subject's body, and the
imaging device is configured to image a plurality of images of the
implanted medical tool.
[0196] In an embodiment, the medical tool includes a medical tool
that is transiently inserted within the portion of the subject's
body, and the imaging device is configured to image a plurality of
images of the medical tool while it is inserted within the
portion.
[0197] In an embodiment, the control unit is configured to enhance
the stabilized set of image frames of the medical tool by image
processing the stabilized set of image frames of the medical
tool.
[0198] In an embodiment, the control unit is configured to
determine a physiological parameter of the subject by analyzing the
stabilized set of image frames.
[0199] In an embodiment, the control unit is configured to
determine a parameter relating to cardiac function of the subject
by analyzing the stabilized set of image frames.
[0200] In an embodiment, the control unit is configured to
determine a parameter relating to respiratory function of the
subject by analyzing the stabilized set of image frames.
[0201] In an embodiment, in generating the stabilized set of image
frames, the control unit is configured to smoothen a transition
between successive frames of the set of frames.
[0202] In an embodiment, the control unit is configured to smoothen
the transition between the successive frames, by:
[0203] determining a characteristic of motion of an object within
the stabilized set of image frames by image processing frames of
the stabilized set of image frames,
[0204] generating a simulated image of the object by assuming that
the object continues to move according to the determined profile,
and
[0205] using the simulated image of the object as an intermediate
image between successive image frames.
[0206] In an embodiment, the control unit is configured to smoothen
the transition between the successive frames, by:
[0207] determining a position of an object within a non-gated image
frame that was acquired subsequent to a first gated image frame and
before a second gated image frame, and
[0208] generating a representation of the object within the
stabilized set of image frames before the second gated image frame
is generated within the stabilized set of image frames.
[0209] In an embodiment, the control unit is configured to
determine a dimension of a region within the portion of the
subject's body, by analyzing the stabilized set of image
frames.
[0210] In an embodiment, the control unit is configured to output
an indication of a size of a medical tool relative to the region
within the portion of the subject's body.
[0211] In an embodiment,
[0212] the apparatus further includes a medical tool configured to
be inserted into the portion of the subject's body and having a
known dimension,
[0213] and the control unit is configured to determine the
dimension of the region by comparing a dimension of the tool within
the stabilized set of image frames to the known dimension.
[0214] In an embodiment, the medical tool includes markers, the
markers being separated from each other by a known distance, and
the control unit is configured to determine an orientation at which
the medical tool is disposed within the portion of the subject's
body by determining a distance between the markers as viewed within
the stabilized set of image frames with respect to the known
distance.
[0215] In an embodiment, the control unit is configured to generate
a simulated image of a virtual medical tool disposed at the
orientation within the stabilized set of image frames of the
portion of the subject's body, in response to the determining of
the distance.
[0216] In an embodiment, the apparatus further includes a user
interface, and the control unit is configured to receive an input
from a user, via the user interface, and to generate a simulated
image of a virtual medical tool disposed within the stabilized set
of image frames of the portion of the subject's body, in response
to receiving the input.
[0217] In an embodiment, the control unit is configured to output
dimensions of a real medical tool that corresponds to the simulated
image of the virtual medical tool.
[0218] In an embodiment, the control unit is configured to output
the dimensions of the real medical tool by accounting for an
orientation at which the virtual medical tool is disposed within
the simulated image.
[0219] In an embodiment, the control unit is configured to output
the dimensions of the real medical tool by accounting for a
curvature of a region of the portion of the subject's body within
which region the virtual medical tool is disposed within the
simulated image.
[0220] In an embodiment, the control unit is configured to receive
a first and a second input from the user and to generate respective
simulated images of first and second medical tools being placed
within the stabilized set of image frames of the portion of the
subject's body, in response to receiving the inputs.
[0221] In an embodiment, the imaging device includes two or more
imaging devices, and the control unit is configured to generate two
or more stabilized sets of image frames of the portion of the
subject's body, the sets of image frames having been imaged by
respective imaging devices of the two or more imaging devices.
[0222] In an embodiment, a first imaging device of the two or more
imaging devices is configured to image the portion of the subject's
body before a medical procedure, a second imaging device of the two
or more imaging devices is configured to image the portion of the
subject's body during the medical procedure, and the control unit
is configured to generate the stabilized sets of image frames
during the medical procedure.
[0223] In an embodiment, a first imaging device of the two or more
imaging devices is configured to image the portion of the subject's
body from outside the portion of the subject's body, and a second
imaging device of the two or more imaging devices is configured to
image regions within the portion of the subject's body while the
second imaging device is disposed at respective locations within
the portion of the subject's body.
[0224] In an embodiment, the control unit is configured to
associate (a) locations within the stabilized image frames acquired
by the first imaging device that correspond to the respective
locations of the second imaging device, with (b) respective image
frames acquired by the second imaging device while the second
imaging device was disposed at the respective locations.
[0225] In an embodiment, the apparatus further includes a medical
tool configured to be inserted into the portion of the subject's
body to a vicinity of the respective locations while the second
imaging device is not disposed at the respective locations, and the
control unit is configured to generate (a) respective image frames
acquired by the second imaging device while the second imaging
device was disposed at the respective locations, when (b) the
medical tool is disposed in a vicinity of the respective
locations.
[0226] In an embodiment, the first imaging device includes a
fluoroscope and the second imaging device includes an intravascular
ultrasound probe.
[0227] In an embodiment, the first imaging device includes a CT
scanner and the second imaging device includes an intravascular
ultrasound probe.
[0228] In an embodiment, the first imaging device is configured to
acquire the plurality of image frames before the second imaging
device images the regions within the portion of the subject's
body.
[0229] In an embodiment, the first imaging device is configured to
acquire the plurality of image frames while the second imaging
device images the regions within the portion of the subject's body,
and the first imaging device is configured to acquire the plurality
of image frames by acquiring a plurality of image frames of the
second imaging device disposed within the portion.
[0230] In an embodiment,
[0231] the stabilized set of image frames defines a first
stabilized set of image frames, and
[0232] the control unit is configured to generate an additional
stabilized set of image frames of the portion of the subject's
body, [0233] by identifying a further given phase of the cyclic
activity of the first body system, and generating an additional set
of the image frames corresponding to image frames of the portion
acquired during the further given phase, and [0234] by image
tracking at least some of the additional set of image frames to
reduce imaged motion of the portion of the subject's body
associated with the additional motion.
[0235] In an embodiment, the given phase includes a systolic phase
of a cardiac cycle of the subject and the further given phase
includes a diastolic phase of the subject's cardiac cycle, and the
control unit is configured to generate sets of image frames which
are stabilized respectively to the systolic and to the diastolic
phases of the subject's cardiac cycle.
[0236] In an embodiment, the apparatus further includes a user
interface, and the control unit is configured to receive an input
from a user, via the user interface, and to generate simulated
images of a virtual medical tool disposed within the stabilized
sets of image frames of the portion of the subject's body at the
given phase and at the further given phase, in response to
receiving the input.
[0237] In an embodiment, the apparatus further includes a medical
tool disposed within the portion of the subject's body, and the
control unit is configured to generate stabilized images of the
medical tool disposed within the portion of the subject's body
respectively at the given phase and at the further given phase.
[0238] In an embodiment, the control unit is configured to
determine a physiological parameter of the subject by comparing the
additional stabilized set of image frames to the first stabilized
set of image frames.
[0239] In an embodiment, the control unit is configured to
determine a parameter relating to cardiac function of the subject
by comparing the additional stabilized set of image frames to the
first stabilized set of image frames.
[0240] In an embodiment, the control unit is configured to
determine a parameter relating to respiratory function of the
subject by comparing the additional stabilized set of image frames
to the first stabilized set of image frames.
[0241] In an embodiment, the cyclic activity includes a cardiac
cycle of the subject, and the sensor includes a sensor for sensing
a phase of the subject's cardiac cycle.
[0242] In an embodiment, the given phase includes an end-diastolic
phase of the subject's cardiac cycle, and the control unit is
configured to generate a stabilized set of the image frames
corresponding to image frames of the portion acquired during the
end-diastolic phase of the subject's cardiac cycle.
[0243] In an embodiment, the sensor includes a blood pressure
sensor.
[0244] In an embodiment, the sensor includes an ECG sensor.
[0245] In an embodiment, the sensor includes an image processor
configured to sense a phase of the subject's cardiac cycle by
comparing image frames of the plurality of image frames to at least
one of the image frames of the plurality of image frames.
[0246] In an embodiment, the cyclic activity includes a respiratory
cycle of the subject, and the sensor includes a sensor for sensing
a phase of the subject's respiratory cycle.
[0247] In an embodiment, the sensor includes an image processor
configured to sense a phase of the subject's respiratory cycle by
comparing image frames of the plurality of image frames to at least
one of the image frames of the plurality of image frames.
[0248] In an embodiment, the additional motion is a result of
cyclic activity of a second body system of the subject, and the
control unit is configured to reduce imaged motion of the portion
of the subject's body associated with the cyclic activity of the
second body system by image tracking at least the set of image
frames.
[0249] In an embodiment,
[0250] the cyclic activity of the first body system has a greater
frequency than the cyclic activity of the second body system,
and
[0251] the control unit is configured to generate the stabilized
set of image frames of the portion of the subject's body: [0252] by
identifying the given phase of the cyclic activity of the first
body system, and outputting the set of the image frames
corresponding to image frames of the portion acquired during the
given phase, and [0253] by image tracking at least the set of image
frames to reduce imaged motion of the portion of the subject's body
associated with the cyclic activity of the second body system.
[0254] In an embodiment,
[0255] the cyclic activity of the first body system has a lower
frequency than a frequency of the cyclic activity of the second
body system, and
[0256] the control unit is configured to generate the stabilized
set of image frames of the portion of the subject's body: [0257] by
identifying the given phase of the cyclic activity of the first
body system, and outputting the set of the image frames
corresponding to image frames of the portion acquired during the
given phase, and [0258] by image tracking at least the set of image
frames to reduce imaged motion of the portion of the subject's body
associated with the cyclic activity of the second body system.
[0259] In an embodiment,
[0260] the cyclic activity of the first body system includes a
cardiac cycle of the subject,
[0261] the cyclic activity of the second body system includes a
respiratory cycle of the subject, and
[0262] the control unit is configured to generate the stabilized
set of image frames of the portion of the subject's body: [0263] by
identifying the given phase of the cardiac cycle, and outputting
the set of the image frames corresponding to image frames of the
portion acquired during the given phase, and [0264] by image
tracking at least the set of image frames to reduce imaged motion
of the portion of the subject's body associated with the
respiratory cycle.
[0265] In an embodiment,
[0266] the cyclic activity of the first body system includes a
respiratory cycle of the subject,
[0267] the cyclic activity of the second body system includes a
cardiac cycle of the subject, and
[0268] the control unit is configured to generate the stabilized
set of image frames of the portion of the subject's body: [0269] by
identifying the given phase of the respiratory cycle, and
outputting the set of the image frames corresponding to image
frames of the portion acquired during the given phase, and [0270]
by image tracking at least the set of image frames to reduce imaged
motion of the portion of the subject's body associated with the
cardiac cycle.
[0271] There is additionally provided, in accordance with an
embodiment of the invention, apparatus for imaging a portion of a
body of a subject that moves as a result of cyclic activity of a
first body system of the subject and that also undergoes additional
motion, and for use with an imaging device for acquiring a
plurality of image frames of the portion of the subject's body, a
sensor for sensing a phase of the cyclic activity of the first body
system, and a display configured to display image frames of the
portion of the subject's body, the apparatus including:
[0272] a control unit configured to generate a stabilized set of
image frames of the portion of the subject's body: [0273] by
identifying a given phase of the cyclic activity of the first body
system, and outputting a set of the image frames corresponding to
image frames of the portion acquired during the given phase, [0274]
by image tracking at least the set of image frames to reduce imaged
motion of the portion of the subject's body associated with the
additional motion,
[0275] wherein the control unit is configured to output the
stabilized set of image frames to be displayed on the display.
[0276] There is further provided, in accordance with an embodiment
of the invention, apparatus for imaging a portion of a body of a
subject that moves as a result of cardiac cyclic activity of the
subject and that also undergoes additional motion that is at least
partially a result of a respiratory cycle of the subject, the
apparatus including:
[0277] an imaging device for acquiring a plurality of image frames
of the portion of the subject's body;
[0278] a sensor for sensing a phase of the cardiac cyclic
activity;
[0279] a control unit configured to generate a stabilized set of
image frames of the portion of the subject's body: [0280] by
identifying a given phase of the cardiac cyclic activity, and
outputting a set of the image frames corresponding to image frames
of the portion acquired during the given phase, and [0281] by image
tracking at least the set of image frames to reduce imaged motion
of the portion of the subject's body associated with the additional
motion; and
[0282] a display configured to display the stabilized set of image
frames of the portion of the subject's body.
[0283] There is additionally provided, in accordance with an
embodiment of the invention, apparatus for use with a portion of a
body of a subject that moves as a result of cyclic activity of a
body system of the subject, the apparatus including:
[0284] a sensor for sensing a phase of the cyclic activity;
[0285] a medical tool configured to perform a function with respect
to the portion of the subject's body; and
[0286] a control unit configured: [0287] in a first cycle of the
cyclic activity, to move at least a portion of the tool in a given
direction, in response to the sensor sensing that the cyclic
activity is at a first given phase thereof, [0288] following the
given phase in the first cycle and prior to an occurrence of the
given phase in a subsequent cycle of the cyclic activity, to
inhibit the movement of the at least a portion of the tool, and
[0289] in a second cycle of the cyclic activity, subsequent to the
inhibiting of the movement, to move the at least a portion of the
tool in the given direction, in response to the sensor sensing that
the second cycle of the cyclic activity is at the given phase
thereof, [0290] without moving the at least a portion of the tool
in a direction opposite to the given direction, between (a) moving
the at least a portion of the tool in
[0291] the given direction in the first cycle, and (b) moving the
at least a portion of
[0292] the tool in the given direction in the second cycle.
[0293] In an embodiment, the control unit is configured to move a
center of the tool by moving the portion of the tool in the given
direction.
[0294] In an embodiment, the tool includes a tool configured to be
controlled remotely by a user.
[0295] In an embodiment, the control unit is configured to be
reversibly coupled to the tool.
[0296] In an embodiment, the control unit is integrated into the
tool.
[0297] In an embodiment, the tool includes a guidewire configured
to be moved within the portion of the subject's body.
[0298] In an embodiment, the tool is configured to penetrate an
occlusion of a lumen of the portion of the subject's body by being
advanced through the lumen.
[0299] In an embodiment, the tool includes a valve configured to be
implanted within the portion of the subject's body by being
expanded within the portion, and the control unit is configured to
move at least a portion of the valve in the given direction, by
moving the at least the portion of the valve in an
expansion-related direction.
[0300] In an embodiment, the tool includes a septal-closure device
configured to be implanted within the portion of the subject's body
by being expanded within the portion, and the control unit is
configured to move at least a portion of the septal-closure device
in the given direction, by moving the at least the portion of the
septal-closure device in an expansion-related direction.
[0301] In an embodiment, the cyclic activity includes a respiratory
cycle of the subject, and the sensor is configured to sense a phase
of the respiratory cycle.
[0302] In an embodiment, the sensor includes an image processor
configured to sense a phase of the subject's respiratory cycle by
comparing image frames of a plurality of image frames of the
portion of the subject's body to at least one of the image frames
of the plurality of image frames.
[0303] In an embodiment, the cyclic activity includes a cardiac
cycle of the subject, and the sensor is configured to sense a phase
of the cardiac cycle.
[0304] In an embodiment, the sensor includes a blood pressure
sensor.
[0305] In an embodiment, the sensor includes an image processor
configured to sense a phase of the subject's cardiac cycle, by
comparing image frames of the plurality of image frames to at least
one of the image frames of the plurality of image frames.
[0306] In an embodiment, the sensor includes an ECG sensor
configured to sense a phase of the cardiac cycle by detecting an
ECG signal of the subject.
[0307] In an embodiment, the tool includes a balloon configured to
be inflated inside a lumen of the portion of the subject's body,
and the control unit is configured to move at least a portion of
the balloon in the given direction, by moving a surface of the
balloon in an inflation-related direction.
[0308] In an embodiment, the control unit is configured to inflate
the balloon continuously for a period of time prior to the first
cycle of the cyclic activity.
[0309] In an embodiment, the control unit is configured to inflate
the balloon continuously for a period of time subsequent to the
second cycle of the cyclic activity.
[0310] In an embodiment, the apparatus further includes a stent,
and the stent is configured to be positioned against a wall of the
lumen via the inflation of the balloon.
[0311] In an embodiment, the apparatus further includes a valve
disposed on the surface of the balloon, and the valve is configured
to be expanded via the inflation of the balloon.
[0312] In an embodiment, the apparatus further includes a valve
configured to control flow to the balloon, and the control unit is
configured to regulate movement of the surface of the balloon in
the inflation-related direction by controlling the valve.
[0313] In an embodiment, the apparatus further includes a tube
configured to supply fluid to the balloon, the apparatus further
includes one or more squeezing surfaces that are disposed around
the tube, and the control unit is configured to inhibit movement of
the surface of the balloon in the inflation-related direction by
driving a current that causes the squeezing surfaces to squeeze
together.
[0314] In an embodiment, the cyclic activity includes a cardiac
cycle of the subject, the portion of the subject's body includes a
portion of a cardiovascular system of the subject that moves as a
result of the subject's cardiac cycle, and the balloon is
configured to be inflated inside the portion of the cardiovascular
system.
[0315] In an embodiment, the given phase of the cardiac cycle
includes end-diastole, and the control unit is configured to move
the surface of the balloon in the inflation-related direction in
response to the sensor sensing end-diastole.
[0316] In an embodiment, the apparatus further includes an
instrument configured to be operated by a user, and the control
unit is configured to move the portion of the tool in the given
direction, (a) in response to the sensor sensing that the cyclic
activity is at the given phase thereof, and (b) in response to the
instrument being operated by the user.
[0317] In an embodiment, the instrument is configured to provide
force feedback to the user that is independent of the cyclic
activity.
[0318] In an embodiment, the instrument is configured to provide
force feedback to the user that is smoothened with respect to the
cyclic activity.
[0319] In an embodiment, the tool includes a tubular structure
configured to bypass an occlusion of a blood vessel within the
portion of the subject's body.
[0320] In an embodiment, the tubular structure includes a blood
vessel graft.
[0321] In an embodiment, the control unit is configured to move the
tubular structure in the given direction by moving a distal end of
the structure in a direction from (a) within the blood vessel on a
proximal side of the occlusion, to (b) outside the blood
vessel.
[0322] In an embodiment, the control unit is configured to move the
tubular structure in the given direction by moving a distal end of
the structure in a direction from (a) outside the blood vessel, to
(b) within the blood vessel on a distal side of the occlusion.
[0323] There is further provided, in accordance with an embodiment
of the invention, apparatus for use with a portion of a body of a
subject that moves as a result of cyclic activity of a body system
of the subject, the apparatus including:
[0324] a sensor for sensing a phase of the cyclic activity;
[0325] a medical tool configured to mechanically perform an action
during a single cycle of the cyclic activity with respect to the
portion of the subject's body; and
[0326] a control unit configured to actuate the tool to
mechanically perform the action in response to the sensor sensing
that the cyclic activity is at a given phase thereof.
[0327] In an embodiment, the tool includes a balloon configured to
apposition itself to a lumen of the portion of the subject's body
during the single cycle by being inflated in response to the sensor
sensing that the cyclic activity is at the given phase thereof.
[0328] In an embodiment, the balloon is configured to be inflated
continuously for a period of time prior to the balloon
appositioning itself to the lumen by being inflated during the
single cycle.
[0329] In an embodiment, the balloon is configured to be inflated
continuously for a period of time subsequent to the balloon
appositioning itself to the lumen by being inflated during the
single cycle.
[0330] In an embodiment, the tool includes a stent configured to
apposition itself to a lumen of the portion of the subject's body
by being expanded inside the lumen of the portion of the subject's
body during a single cycle of the cyclic activity, in response to
the sensor sensing that the cyclic activity is at the given phase
thereof.
[0331] In an embodiment, the stent includes a self-expansible
portion configured to self-expand inside the lumen of the portion
of the subject's body.
[0332] In an embodiment, the tool includes a valve configured to be
implanted within the portion of the subject's body by mechanically
expanding within the portion, and the control unit is configured to
actuate the valve to expand in response to the sensor sensing that
the cyclic activity is at the given phase thereof.
[0333] In an embodiment, the cyclic activity includes a cardiac
cycle of the subject, and the control unit is configured to actuate
the valve to expand in response to the sensor sensing that the
cardiac cycle is at the given phase thereof.
[0334] In an embodiment, the given phase includes an end-diastolic
phase of the cardiac cycle, and the control unit is configured to
actuate the valve to expand in response to the sensor sensing the
end-diastolic phase of the cardiac cycle.
[0335] In an embodiment, the tool includes a septal-closure device
configured to be implanted within a heart of the subject by
mechanically expanding within the heart, and the control unit is
configured to actuate the septal-closure device to expand in
response to the sensor sensing that cardiac cyclic activity of the
subject is at a given phase thereof.
[0336] In an embodiment, the given phase includes an end-diastolic
phase of the cardiac cycle, and the control unit is configured to
actuate the septal-closure device to expand in response to the
sensor sensing the end-diastolic phase of the cardiac cycle.
[0337] There is further provided, in accordance with an embodiment
of the invention, apparatus for use with a portion of a subject's
body that undergoes neural cyclic activity, the apparatus
including:
[0338] a sensor for sensing a phase of the neural cyclic
activity;
[0339] a medical tool configured to perform a function with respect
to the portion of the subject's body; and
[0340] a control unit configured to actuate the tool to perform the
function, in response to the sensor sensing that the cyclic
activity is at a given phase thereof.
[0341] There is additionally provided, in accordance with an
embodiment of the present invention, apparatus for use with a
portion of a body of a subject that moves as a result of cyclic
activity of a body system of the subject, and for use with a sensor
for sensing a phase of the cyclic activity, and for use with a
medical tool configured to perform a function with respect to the
portion of the subject's body, the apparatus including:
[0342] a control unit configured: [0343] in a first cycle of the
cyclic activity, to move at least a portion of the tool in a given
direction, in response to the sensor sensing that the cyclic
activity is at a given phase thereof, [0344] following the given
phase in the first cycle and prior to an occurrence of the given
phase in a subsequent cycle of the cyclic activity, to inhibit the
movement of the at least a portion of the tool, and [0345] in a
second cycle of the cyclic activity, subsequent to the inhibiting
of the movement, to move the at least a portion of the tool in the
given direction, in response to the sensor sensing that the second
cycle of the cyclic activity is at the given phase thereof, [0346]
without moving the at least a portion of the tool in a direction
opposite to the given direction, between (a) moving the at least a
portion of the tool in
[0347] the given direction in the first cycle, and (b) moving the
at least a portion of
[0348] the tool in the given direction in the second cycle.
[0349] There is further provided, in accordance with an embodiment
of the invention, apparatus for use with a portion of a body of a
subject that moves as a result of cyclic activity of a body system
of the subject, the apparatus including:
[0350] a sensor for sensing a phase of the cyclic activity;
[0351] a medical tool configured to perform a function with respect
to the portion of the subject's body; and
[0352] a control unit configured: [0353] in a first cycle of the
cyclic activity in response to the sensor sensing that the cyclic
activity is at a first given phase thereof, to move the tool,
[0354] in a subsequent cycle of the cyclic activity in response to
the sensor sensing that the cyclic activity is at the given phase
thereof, to actuate the tool to execute an action selected from the
group consisting of: performing the function and moving, [0355]
following the given phase in the subsequent cycle and prior to an
occurrence of the given phase in a further subsequent cycle of the
cyclic activity, to inhibit the selected action of the tool, and
[0356] in the further subsequent cycle of the cyclic activity,
subsequent to the inhibiting of the action, and in response to the
sensor sensing that the further subsequent cycle of the cyclic
activity is at the given phase thereof, to actuate the tool to
execute an action selected from the group.
[0357] In an embodiment, the tool includes a myocardial
revascularization tool configured to sequentially apply a
revascularization treatment to respective treatment sites within
the portion of the subject's body, and the control unit is
configured to:
[0358] actuate the tool to perform the function by actuating the
tool to apply a revascularization treatment to a treatment site,
and
[0359] to move the tool by moving at least a portion of the
revascularization tool toward successive treatment sites.
[0360] In an embodiment, the control unit is configured to move the
tool by moving the tool to create a defined pattern of treatment
sites.
[0361] In an embodiment, the tool includes an ablation tool
configured to sequentially ablate respective ablation sites within
the portion of the subject's body, and the control unit is
configured to:
[0362] actuate the tool to perform the function by actuating the
tool to ablate an ablation site, and
[0363] to move the tool by moving at least a portion of the
ablation tool toward successive ablation sites.
[0364] In an embodiment, the ablation tool is configured to ablate
the ablation sites using an ablation technique selected from the
group consisting of: laser ablation, electrocautery, RF ablation,
cryogenic ablation, and ultrasound ablation.
[0365] In an embodiment, the control unit is configured to move the
at least the portion of the tool by moving the at least the portion
of the tool to create a defined pattern of ablation sites.
[0366] In an embodiment, the control unit is configured to apply a
Maze procedure to the ablation sites by moving the at least the
portion of the tool toward successive ablation sites.
[0367] In an embodiment, the ablation tool is configured to apply a
pulmonary vein isolation technique to a heart of the subject by
moving the at least the portion of the tool toward successive
isolation sites.
[0368] In an embodiment, the tool includes an injection tool,
configured to inject a substance within the portion of the
subject's body, and the control unit is configured to:
[0369] actuate the tool to perform the function by actuating the
tool to inject the substance, and
[0370] to move the tool by moving at least a portion of the tool
toward an injection site.
[0371] In an embodiment, the substance includes DNA molecules, and
the injection tool is configured to inject the DNA molecules into
heart tissue of the subject.
[0372] In an embodiment, the substance includes stem cells, and the
injection tool is configured to inject the stem cells into heart
tissue of the subject.
[0373] In an embodiment, the tool includes a needle configured to
suture tissue within the portion of the subject's body, and the
control unit is configured to:
[0374] actuate the tool to perform the function by actuating the
tool to suture the tissue, and
[0375] to move the tool by moving the needle toward successive
suturing sites.
[0376] In an embodiment, the tissue includes tissue of the subject
selected from the group consisting of cardiac tissue and coronary
tissue, and the needle is configured to suture the selected
tissue.
[0377] In an embodiment, the tool includes a needle configured to
aspirate tissue from an aspiration site within the portion of the
subject's body, and the control unit is configured to:
[0378] actuate the needle to perform the function by actuating the
needle to aspirate the tissue, and
[0379] move the needle by moving the needle toward the aspiration
site.
[0380] In an embodiment, the needle is configured to perform
trans-thoracic needle aspiration.
[0381] In an embodiment, the needle is configured to perform
trans-bronchial needle aspiration.
[0382] There is additionally provided, in accordance with an
embodiment of the invention, apparatus for opening an at least
partial occlusion of a lumen of a subject's body, the apparatus
including:
[0383] a sensor for sensing a phase of the cyclic activity;
[0384] an occlusion-opening tool configured to open the occlusion;
and
[0385] a control unit configured: [0386] in a first cycle of the
cyclic activity in response to the sensor sensing that the cyclic
activity is at a first given phase thereof, to actuate the tool to
perform an occlusion-opening action, [0387] following the given
phase in the first cycle and prior to an occurrence of the given
phase in a subsequent cycle of the cyclic activity, to inhibit the
action of the tool, and [0388] in a second cycle of the cyclic
activity, subsequent to the inhibiting of the action, and in
response to the sensor sensing that the second cycle of the cyclic
activity is at the given phase, to actuate the tool to perform the
action.
[0389] In an embodiment, after actuating the tool at the given
phase of the first cycle and before the actuation of the tool at
the given phase of the subsequent cycle, the control unit is
configured to retract the tool from the occlusion.
[0390] In an embodiment, the occlusion-opening tool includes a tool
configured to open the occlusion by directing acoustic waves toward
the occlusion.
[0391] There is further provided, in accordance with an embodiment
of the invention, apparatus for use with a portion of a body of a
subject that moves as a result of cyclic activity of a body system
of the subject, the apparatus including:
[0392] an imaging device for acquiring a plurality of image frames
of the portion of the subject's body;
[0393] a sensor for sensing a phase of the cyclic activity;
[0394] a medical tool configured to perform a function with respect
to the portion of the subject's body;
[0395] a control unit configured to: [0396] generate a stabilized
set of image frames of the medical tool disposed within the portion
of the subject's body, [0397] actuate the tool to execute an action
selected from the group consisting of performing the function and
moving, in response to the sensor sensing that the cyclic activity
is at a given phase thereof, and [0398] inhibit the tool from
executing the action in response to the sensor sensing that the
cyclic activity is not at the given phase; and
[0399] a display configured to facilitate use of the tool by
displaying the stabilized set of image frames of the medical tool
disposed within the portion of the subject's body.
[0400] In an embodiment, the apparatus further includes a user
interface, and the control unit is configured to receive an input
from a user, via the user interface, and to designate the given
phase in response to the input.
[0401] In an embodiment, the tool includes a valve configured to be
implanted within the portion of the subject's body by being
expanded within the portion, and the control unit is configured to
actuate the valve by expanding the valve.
[0402] In an embodiment, the tool includes a septal-closure device
configured to be implanted within the portion of the subject's body
by being expanded within the portion, and the control unit is
configured to actuate the septal-closure device by expanding the
septal closure device.
[0403] In an embodiment, the tool includes a balloon configured to
perform the function by being inflated inside a lumen of the
portion of the subject's body.
[0404] In an embodiment, the tool includes a tubular structure
configured to bypass an occlusion of a blood vessel within the
portion of the subject's body.
[0405] In an embodiment, the tool includes a myocardial
revascularization tool configured to sequentially apply a
revascularization treatment to respective treatment sites within
the portion of the subject's body, and the control unit is
configured to:
[0406] actuate the tool to perform the function by actuating the
tool to apply a revascularization treatment to a treatment site,
and
[0407] move the tool by moving at least a portion of the
revascularization tool toward successive treatment sites.
[0408] In an embodiment, the tool includes an ablation tool
configured to sequentially ablate respective ablation sites within
the portion of the subject's body, and the control unit is
configured to:
[0409] actuate the tool to perform the function by actuating the
tool to ablate an ablation site, and
[0410] move the tool by moving at least a portion of the ablation
tool toward successive ablation sites.
[0411] In an embodiment, the tool includes an injection tool
configured to inject a substance within the portion of the
subject's body and the control unit is configured to:
[0412] actuate the tool to perform the function by actuating the
tool to inject the substance, and
[0413] move the tool by moving at least a portion of the tool
toward an injection site.
[0414] In an embodiment, the tool includes a needle configured to
suture tissue within the portion of the subject's body, and the
control unit is configured to:
[0415] actuate the tool to perform the function by actuating the
tool to suture the tissue, and
[0416] move the tool by moving the needle toward successive
suturing sites.
[0417] In an embodiment, the tool includes a needle configured to
aspirate tissue from an aspiration site within the portion of the
subject's body, and the control unit is configured to:
[0418] actuate the needle to perform the function by actuating the
needle to aspirate the tissue, and
[0419] move the needle by moving the needle toward the aspiration
site.
[0420] In an embodiment, the tool includes an occlusion-opening
tool configured to perform the function by performing an
occlusion-opening action on an at least partial occlusion of a
lumen of the portion of the subject's body.
[0421] In an embodiment, the tool is configured to perform the
occlusion-opening action by moving toward the occlusion, and after
actuating the tool at the given phase of a first cycle and before
the actuation of the tool at the given phase of a subsequent cycle,
the control unit is configured to retract the tool from the
occlusion.
[0422] In an embodiment, the control unit is configured to generate
the stabilized set of image frames by image tracking at least some
of the plurality of image frames to reduce imaged motion of the
portion of the subject's body associated with the cyclic
activity.
[0423] In an embodiment, the control unit is configured to generate
the stabilized set of image frames by generating a set of tracked
image frames corresponding to image frames of the portion acquired
during the given phase.
[0424] In an embodiment, the control unit is configured to generate
the stabilized set of image frames by generating a set of the image
frames corresponding to image frames of the portion acquired during
the given phase.
[0425] In an embodiment, the control unit is configured to reduce
imaged motion of the portion of the subject's body associated with
motion of the portion of the subject's body by image tracking the
set of image frames.
[0426] In an embodiment, the control unit is configured to generate
the set of image frames corresponding to image frames of the
portion acquired during the given phase, by actuating the imaging
device to acquire the plurality of image frames only when the
cyclic activity is at the given phase.
[0427] In an embodiment, the imaging device is configured to
acquire the plurality of image frames throughout the cyclic
activity, and the control unit is configured to generate the set of
image frames corresponding to image frames of the portion acquired
during the given phase by selecting image frames corresponding to
image frames of the portion acquired during the given phase from
the plurality of image frames.
[0428] In an embodiment, the control unit is configured to generate
an additional stabilized set of image frames of the portion of the
subject's body, by identifying a further given phase of the cyclic
activity of the body system, and generating a set of the image
frames corresponding to image frames of the portion acquired during
the further given phase.
[0429] In an embodiment, the cyclic activity includes a cardiac
cycle of the subject, and the sensor includes a sensor for sensing
a phase of the subject's cardiac cycle.
[0430] In an embodiment, the given phase includes an end-diastolic
phase of the subject's cardiac cycle, and the control unit is
configured to generate a stabilized set of the image frames
corresponding to image frames of the portion acquired during the
end-diastolic phase of the subject's cardiac cycle.
[0431] In an embodiment, the sensor includes an image processor
configured to sense movement of the portion of the subject's body
by comparing image frames of the plurality of image frames to at
least one of the plurality of image frames.
[0432] In an embodiment, the cyclic activity includes a respiratory
cycle of the subject, and the sensor includes a sensor for sensing
a phase of the subject's respiratory cycle.
[0433] In an embodiment, the sensor includes an image processor
configured to sense movement of the portion of the subject's body
by comparing image frames of the plurality of image frames to at
least one of the plurality of image frames.
[0434] In an embodiment, the apparatus further includes an
instrument configured to be operated by a user, and the control
unit is configured to actuate the tool to perform the function, (a)
in response to the sensor sensing that the cyclic activity is at
the given phase thereof, and (b) in response to the instrument
being operated by the user.
[0435] In an embodiment, the instrument is configured to provide
force feedback to the user that is independent of the cyclic
activity.
[0436] In an embodiment, the instrument is configured to provide
force feedback to the user that is smoothened with respect to the
cyclic activity.
[0437] There is further provided, in accordance with an embodiment
of the invention, apparatus for use with a portion of a body of a
subject that moves as a result of cyclic activity of a body system
of the subject, and for use with an imaging device for acquiring a
plurality of image frames of the portion of the subject's body, a
sensor for sensing a phase of the cyclic activity, a medical tool
configured to perform a function with respect to the portion of the
subject's body, and a display configured to facilitate use of the
tool by displaying image frames of the portion of the subject's
body, the apparatus including:
[0438] a control unit configured to: [0439] generate a stabilized
set of image frames of the portion of the subject's body, [0440]
output the stabilized set of image frames to the display, [0441]
actuate the tool to perform the function in response to the sensor
sensing that the cyclic activity is at a given phase of the cyclic
activity, and [0442] inhibit the tool from performing the function
in response to the sensor sensing that the cyclic activity is not
at the given phase.
[0443] There is additionally provided, in accordance with an
embodiment of the present invention, apparatus for use with a
portion of a body of a subject that moves as a result of cyclic
activity of a body system of the subject, the apparatus
including:
[0444] an imaging device for acquiring a plurality of image frames
of the portion of the subject's body;
[0445] a sensor for sensing a phase of the cyclic activity;
[0446] a medical tool configured to mechanically perform an action
during a single cycle of the cyclic activity with respect to the
portion of the subject's body; and
[0447] a control unit configured to: [0448] generate a stabilized
set of image frames of the portion of the subject's body, and
[0449] actuate the tool to mechanically perform the action in
response to the sensor sensing that the cyclic activity is at a
given phase thereof.
[0450] In an embodiment, the control unit is configured to generate
the stabilized set of image frames by generating a set of image
frames that are stabilized with respect to the given phase of the
cyclic activity.
[0451] In an embodiment, the tool includes a balloon configured to
apposition itself to a lumen of the portion of the subject's body
during a single cycle by being inflated, in response to the sensor
sensing that the cyclic activity is at the given phase thereof.
[0452] In an embodiment, the tool includes a stent configured to be
implanted by being expanded inside a lumen of the portion of the
subject's body during a single cycle of the cyclic activity, in
response to the sensor sensing that the cyclic activity is at the
given phase thereof.
[0453] In an embodiment, the tool includes a valve configured to be
implanted within the portion of the subject's body by mechanically
expanding within the portion during a single cycle of the cyclic
activity, in response to the sensor sensing that the cyclic
activity is at the given phase thereof.
[0454] In an embodiment, the tool includes a septal-closure device
configured to be implanted within a heart of the subject by
mechanically expanding within the heart during a single cycle of
cardiac cyclic activity of the subject, in response to the sensor
sensing that the cyclic activity is at the given phase thereof.
[0455] 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
[0456] FIG. 1 is a schematic illustration of apparatus for
generating a stabilized image of a portion of a subject's body, in
accordance with an embodiment of the present invention;
[0457] FIG. 2 is a schematic illustration of a heart at various
phases of the cardiac cycle alongside an ECG signal associated with
the cardiac cycle;
[0458] FIG. 3 is a schematic illustration of image frames of a
subject's heart being gated to a phase of a physiological cycle, in
accordance with an embodiment of the present invention;
[0459] FIG. 4 is a schematic illustration of image frames of a
subject's heart being image tracked, in accordance with an
embodiment of the present invention;
[0460] FIG. 5 is a schematic illustration of image frames of a
subject's heart being (a) gated to a phase of a physiological
cycle, and (b) image tracked, in accordance with an embodiment of
the present invention;
[0461] FIG. 6 is a schematic illustration of apparatus for
synchronizing actuation of a medical device with a physiological
cycle, in accordance with an embodiment of the present
invention;
[0462] FIGS. 7A-B are schematic illustrations of the actuation of
inflation of a balloon in synchronization with a physiological
cycle, in accordance with an embodiment of the present
invention;
[0463] FIG. 7C is a graph schematically showing the pressure of the
balloon as a function of time, in accordance with an embodiment of
the present invention;
[0464] FIG. 8 is a schematic illustration of apparatus for
facilitating the synchronized inflation of a balloon, in accordance
with an embodiment of the present invention;
[0465] FIGS. 9-11 are schematic illustrations of apparatus for
facilitating the synchronized inflation of a balloon, in accordance
with another embodiment of the present invention;
[0466] FIG. 12 is a schematic illustration of apparatus for
facilitating the synchronized inflation of a balloon, the apparatus
being built into an inflation device, in accordance with a further
embodiment of the present invention;
[0467] FIG. 13 is a schematic illustration of synchronization of
the penetration of an occlusion of a blood vessel with cyclic
movement of the blood vessel, in accordance with an embodiment of
the present invention;
[0468] FIG. 14 is a schematic illustration of a modulator for
synchronizing the penetration of an occlusion of a blood vessel
with the cyclic movement of the blood vessel, in accordance with an
embodiment of the present invention;
[0469] FIG. 15 is a schematic illustration of a handheld actuator
that comprises the modulator shown in FIG. 14, in accordance with
an embodiment of the present invention; and
[0470] FIG. 16 is a schematic illustration of the synchronization
of a transluminal placement of a coronary bypass graft with the
cyclic motion of a portion of the subject's body, in accordance
with an embodiment of the present invention.
DETAILED DESCRIPTION OF EMBODIMENTS
[0471] As used herein: [0472] The term "physiological signal or
process" refers to any cyclical physiological signal or process in
the patient's body including, but not limited to, ECG, blood
pressure (e.g., systolic and diastolic), Peripheral Arterial Tone,
EEG, respiration, the shifting/expansion/contraction of an organ,
acquired images in which any of the above signals or processes may
be observed, or any combination, derivation, extrapolation or
manipulation thereof. [0473] The terms "medical tool," "tool" and
"probe" mean 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 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
guide wire, a suturing 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, an imaging device, a
sensing probe, a probe comprising an optical fiber, a robotic tool,
a tool that is controlled remotely, or any combination thereof.
[0474] The terms "image" and "imaging" refer to any type of medical
imaging, typically presented as a sequence of images and including
ionizing radiation, non-ionizing radiation, video, fluoroscopy,
angiography, ultrasound, CT, MRI, PET, PET-CT, CT angiography,
SPECT, Gamma camera imaging, Optical Coherence Tomography (OCT),
Vibration 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),
etc. [0475] The terms "periodic" and "cyclical," when used in the
context of the motion of a body organ, are interchangeable. [0476]
The terms "gating" and "synchronization," and their various
derivations, when used in the context of synchronizing between an
image display and one or more physiological signals or processes or
between the activation of a medical tool and one or more
physiological signals or processes, are interchangeable. (The term
"coherence" has also been known to describe the same.) [0477] The
terms "stationary" and "stabilized," when used in the context of
displayed images, mean a display of a series of images in a manner
such that the periodic or cyclical motion of the body organ(s)
being imaged is typically, partially or fully, reduced or not
noticeable to the viewer. Typically, such images are gated to one
or more physiological signals or processes whose cycle(s)
correspond to a motion cycle of the organ being imaged. [0478] The
term "virtual stabilization," when used in reference to a moving
organ, refers to a situation where the displayed images of said
organ are stabilized, partially or fully, with respect to the
motion of the organ, and/or tool(s) applied to the organ are
actuated in synchronization with a selected phase in the motion of
the organ. (Motion of the organ may comprise cyclical and
non-cyclical motion.) Consequently, the moving organ is typically
viewed and/or acted upon as if it is in a situation of (partial or
full) virtual stabilization. [0479] The terms "synchronizing" and
"gating," and derivations thereof, when used in reference to an
image stream, describes the identification and selection of
individual image frames from such image stream, wherein such frames
are acquired at a same selected phase in a plurality of occurrences
of a cyclical physiological signal or process. [0480] The term
"gating," and derivations thereof, when used in reference to a
medical tool, describes the movement and/or application of the tool
at a same selected phase in a plurality of occurrences of a
cyclical physiological signal or process. [0481] The term "image
tracking" is used to describe a process by which images (including
images acquired at different phases in the motion of an organ) are
aligned to one another by means of aligning among such images one
or more features, or regions of interest, that are observable in
most or all images. The term should be construed to be synonymous
with the terms "video tracking," "frame tracking," and "object
tracking." [0482] The term "real time," when used in reference to
the application of virtual stabilization or of an element thereof,
means without a noticeable delay. [0483] The term "near real time,"
when used in reference to the application of virtual stabilization
or of an element thereof, 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 4 seconds).
[0484] In some embodiments, apparatus and methods are provided for
facilitating medical procedures performed on cyclically-moving
organs, so that such procedures are performed under a partial or
full virtual stabilization of such organs. The virtual
stabilization typically comprises two elements, namely (a) the
stabilization of the image(s) of the organ and (b) the
synchronization of tool(s) being actuated and/or moved, with the
movement of the organ. At least one of these two major elements is
applied.
[0485] Examples of organs which move cyclically include, but are
not limited to, the heart, the coronary blood vessels, the aorta,
certain other blood vessels (e.g., renal, carotid), the majority of
the respiratory tract, certain parts of the digestive tract (e.g.,
the stomach, the small intestine), certain parts of the thorax
(e.g., the diaphragm), the eyes, etc. The description hereinbelow
relates mainly to the example of the body organ being the heart
and/or the coronary blood vessels, and the physiological signal
used for synchronization or gating in such examples is typically
the ECG. However, the scope of the invention includes applying the
apparatus and methods described hereinbelow to any portion of a
subject's body that moves as a result of the cyclic activity of a
body-system of the subject.
[0486] Reference is now made to FIG. 1, which is a schematic
illustration of apparatus for acquiring image frames of a portion
of a subject's heart, in accordance with an embodiment of the
present invention. An angiographic/fluoroscopic camera 11 acquires
a plurality of image frames, throughout the cyclic activity of the
heart. When the image frames are not stabilized, an image or video
stream 14 is generated, which is blurred due to the cyclical motion
of the imaged heart.
[0487] In some embodiments, the apparatus generates a stabilized
video stream 15 by a gating procedure performed by processor 13 in
response to an ECG signal 12, a blood pressure sensor, a
displacement sensor, a vibration sensor and/or any combinations or
derivations thereof, thus yielding said stabilized image or video
stream 15. Alternatively or additionally, the image frames are
gated with respect to the subject's respiratory cycle. In some
embodiments, the subject's respiratory cycle is detected by means
of a respiration sensor, such as a stretch belt, a displacement
sensor, a vibration sensor, and/or any combinations or derivations
thereof.
[0488] In some embodiments, the aforementioned gating is performed
directly in conjunction with the actual expansion and contraction
of the heart muscle in the course of the cardiac cycle, as such
expansion process is observed by the fluoroscopic/angiographic
camera, discerning by means of image processing the relative
distances among identifiable features such as the coronary blood
vessels.
[0489] In some embodiments, gating is performed initially with
respect to the ECG signal, or to another signal corresponding to
cardiac motion, and/or to any combination or derivation of signals
thereof, but afterwards gating is performed by means of image
processing. For example, an image frame corresponding to a selected
phase in the ECG signal is identified and determined to be a
"baseline image frame." After such identification of a "baseline
image frame" has been achieved, gating of the subsequent image
stream is done by means of selecting those image frames where the
shape of the observed anatomy is identical, or most similar, to the
shape observed in the baseline image frame.
[0490] For some applications, the aforementioned gating is applied
directly to the radiation source of the fluoroscopic/angiographic
camera, so that imaging is performed intermittently, e.g., only
during or leading up to one or more specific phases in the cardiac
cycle at which the acquisition of a (gated) image frame is
desired.
[0491] Techniques described herein, above or below, may be
practiced in combination with techniques described in one or more
of the references cited in the Background section of this
application.
[0492] The stabilized image frames are typically produced at the
rate of the patient's heart rate. The resulting frame rate is
typically one or two frames per second, which is considered a
low-frame rate compared to what the human eye interprets as
continuous. In some embodiments, a gap filling technique is applied
among the image frames that were selected for display by the
gating. Additional intermediate image frames are generated, thus
increasing the visible frame rate, typically smoothening the
transitions among the gated and displayed images and making the
image stream easier to observe. In some embodiments, such gap
filling utilizes image processing methods such as blending,
morphing or a combination thereof.
[0493] In some embodiments, the gap-filling techniques include a
predictive algorithm that is applied to generate image frames after
the most recent gated and displayed image frame, but prior to the
next gated and displayed image frame. For example, an image
processor determines a characteristic of motion of the tool, based
upon previously-acquired image frames. The motion profile is
extrapolated to generate a simulated image frame of the tool by
assuming that the tool continues to move according to the
determined profile. The simulated image frame is then used as an
intermediate image between successive image frames.
[0494] In some embodiments of the gap-filling, visual information
from images that were acquired in the original image stream, but
are not displayed in the gated image stream, may be used to discern
some of the changes that have occurred since the most recent gated
and displayed image. Those changes are then applied to the most
recent gated and displayed image, to generate new image frames
ahead of the next gated and displayed image. For example, in a
beating heart wherein medical tools are manipulated, such visual
information may comprise changes in tool positions relative to
visible anatomical landmarks that move together with the heart.
Such changes are then applied to the most recent gated and
displayed image, leading to a representation of the tool being
generated and displayed within the stabilized video stream ahead of
the next gated and displayed image frame.
[0495] The gap filling described hereinabove is applied by
processor 13. Typically, it is applied in the transition between
every two consecutive gated image frames. The resulting, stabilized
video stream is typically displayed in the course of the procedure,
and typically in real time or in near real time.
[0496] In some embodiments, the stabilized video stream is stored
and is displayed subsequent to the procedure in which the image
frames are acquired.
[0497] In some embodiments, two or more of the streams of images,
including the original "jumpy" images and the "smoothened" gated
images, are displayed side by side (which may be achieved using two
or more separate physical displays, or using two or more software
windows within the same physical display).
[0498] In some embodiments, the "smoothened," gated image stream is
displayed in a shared manner on the same display that is used for
other purposes in the procedure room, such as on an existing "main"
or "reference" or "re-loop" display in a coronary catheterization
lab.
[0499] Reference is now made to FIG. 2, which is a schematic
illustration of a heart at various phases of the cardiac cycle
alongside an ECG signal associated with the cardiac cycle. FIG. 2
illustrates the correspondence between triggering points 21, 22 and
23 in the ECG trace and phases 24, 25 and 26 in the cardiac cycle.
Different points in the ECG trace typically correspond to different
phases in the cardiac cycle. The volume and shape of the heart
typically vary throughout the cardiac cycle. The displayed images
of the pulsating heart may be gated to any of these points or
phases. In some embodiments, the heart may therefore be
continuously viewed at a specific volume and/or shape.
[0500] In some embodiments, an operator (e.g., an interventional
cardiologist) shifts the phase point to view the cardiac image at
any desired phase in the cycle of the ECG signal, via an input to
processor 13 (shown in FIG. 1). In some embodiments, the specific
phase of the cardiac cycle to which the displayed images are gated
may be changed by the operator in the course of viewing the
images.
[0501] In some embodiments, the stabilized video stream is gated
specifically to the end of the diastolic phase of the cardiac
cycle. (At the end-diastolic phase the ventricles are typically at
their peak volume.) In addition, the inventors hypothesize that the
coronary blood vessels may be spread apart at the end-diastolic
phase of the cardiac cycle, and, for example, in the case of an
angioplasty procedure, that may be the view most desired by a
physician. Alternatively the stabilized video stream is gated to a
different phase of the subject's cardiac cycle, for example,
systole, or mid-diastole.
[0502] In some embodiments, more than one stabilized video stream
is displayed concurrently. For example, a stabilized video stream
at a diastolic phase of the cardiac cycle is displayed concurrently
with another stabilized video stream at a systolic phase of the
cardiac cycle.
[0503] In some embodiments, the gated images at different phases of
the cardiac cycle form a basis for determining a parameter of the
subject's cardiovascular system, for example, the ejection fraction
of the heart (using image processing techniques known in the art,
mutatis mutandis). In some embodiments, image streams are
stabilized with respect to two or more phases of the subject's
respiratory cycle, and a parameter of the subject's respiratory
cycle is determined using one, or both of the image streams, for
example, by comparing the image streams to each other. For example,
the subject's tidal volume may be determined by determining from
the image streams the size of the subject's lungs at the end of the
exhalation phase of the subject's respiratory cycle and the size of
the subject's lungs at the end of the inhalation phase of the
cycle.
[0504] In some embodiments, processor 13 (FIG. 1) stabilizes the
image of the portion of the subject's body with respect to
additional motion of the portion. Some physiological signals or
processes correspond to a change in the shape of the organs being
imaged. Other signals or processes mainly correspond to a change in
the location of such organs but have less of a correspondence to
their shape. In some cases, signals or processes of those two
categories apply to a certain organ or organs concurrently. For
example, in the case of the heart and the coronary blood vessels,
those organs typically twist, contract and expand in the course of
the cardiac cycle (also corresponding to the ECG signal), while at
the same time they also typically shift up and down in the course
of the respiratory cycle. In addition, such organs may shift in a
non-cyclical manner due to "whole-body motion" of the subject, for
example, due to the subject coughing or moving on his/her bed.
("Whole-body motion" is to be understood as referring to
non-cyclical, noticeable motion of an external portion of the
subject's body, even in the absence of the subject's entire body
moving.)
[0505] In some embodiments, for the creation of a stabilized video
stream of the organ(s) being imaged, a cyclical signal or process
typically corresponding to a change in the shape(s) of such
organ(s) is accounted for by means of gating. Subsequently, another
signal or process, typically corresponding mainly to a change in
the location of such organs, is accounted for by means of an image
tracker. For example, in the case of the heart and/or associated
blood vessels, gating to the ECG signal is applied to create one or
more video streams, each of which is stabilized with respect to a
specific phase in the cardiac cycle. Image tracking is then applied
to the aforementioned gated video stream(s) in order to further
stabilize the stream(s) with respect to the respiratory cycle.
[0506] In some embodiments, gating followed by image tracking is
applied to respective image frames, in a frame-by-frame manner,
such that an individual gated frame is image tracked prior to the
next gated frame being acquired. Alternatively, gating is applied
to a batch of image frames to generate a set of gated image frames.
Image tracking is then applied to the set of gated image
frames.
[0507] In some embodiments, the image tracker is applied to motion
that is typically not of a cyclical nature, such as whole-body
motion of the patient in the course of the procedure. As a result,
such motion of the patient is absent from, or substantially reduced
in, the stabilized image stream being viewed by the physician.
[0508] The sequence in which the aforementioned gating, image
tracking and gap filling are applied to images in the
originally-acquired image stream may vary.
[0509] In some embodiments, and for the purpose of creating a
stabilized video stream of a cyclically-moving organ, the typically
higher frequency of two physiological signals or processes
corresponding to a motion of said organ is gated, and subsequently
the signal or process which is typically of a lower frequency,
and/or any additional motion of the organ, is accounted for by
means of image tracking. For example, such sequence may reduce the
computational resources required for image stabilization.
Alternatively, the typically lower frequency of the two
physiological signals or processes is gated, and the signal or
process which is typically of a higher frequency, and/or any
additional motion of the organ, is accounted for by means of image
tracking.
[0510] In some embodiments, the stabilization of the video stream
of the cyclically-moving organ is achieved by accounting for the
second aforementioned signal or process by means of image tracking
prior to (and not following) accounting for the first
aforementioned signal or process by means of gating. For example,
such a sequence may be useful in some of the aforementioned
gap-filling algorithms.
[0511] Specifically, for some applications, visual information of
changes in tool positions relative to anatomical landmarks is
easier to identify in image tracked images before the images are
gated.
[0512] In some embodiments, image tracking followed by gating is
applied to respective image frames (typically, in real time or near
real time). Alternatively, a batch of image frames are image
tracked and subsequently the tracked image frames are gated.
[0513] In some embodiments, image frames are gated with respect to
the respiratory cycle, and are image-tracked with respect to
movement related to the subject's cardiac cycle.
[0514] The image tracker applied in the aforementioned embodiments
may be an edge tracker, a centroid tracker, a correlation tracker,
an object tracker, or any combination thereof. Such image tracker
typically neutralizes, in the eyes of the viewer of a stabilized
video stream, the change in location of the organs being imaged,
thus maintaining the organ at a desired location on the display
(such as its center), even though the organ being imaged is in
constant motion.
[0515] Reference is now made to FIG. 3 which is a schematic
illustration of a video stream 33 of a subject's heart being gated
to a phase of the subject's cardiac cycle, in accordance with an
embodiment of the present invention. A video camera 31, acquires a
video stream 33 of the subject's heart. An ECG 32 detects the
subject's cardiac cycle. A gating processor 34 of control unit 13
(FIG. 1) selects image frames 35 corresponding to a given phase of
the cardiac cycle as reflected by a given point in ECG 32. In some
embodiments, a buffer 36 is used for gap filling the transitions
among images 35. The resulting stabilized video stream is presented
on display 37. Reference is now made to FIG. 4, which is a
schematic illustration of a video stream 41 of a subject's heart
being image tracked, in accordance with an embodiment of the
present invention. Typically, video stream 41 is the output of
gating processor 34 (FIG. 3). A mask 45 is generated from image
frames of video stream 41 of the subject's heart. Both mask 45 and
the image frames are fed into a correlator 42. Correlator 42
identifies mask 45 in each new image frame, and by doing so
identifies the deviation in the location of the mask within the
current image frame relative to its location in the prior image
frame. Image corrector 43 utilizes the output of correlator 42 for
realigning each new image frame such that the relative location of
mask 45 within each such new image frame remains constant.
Consequently, tracked video stream 44 is produced. In embodiments
in which the input to correlator 42 and image corrector 43 is the
output of gating processor 34 (FIG. 3), video stream 44 is both
image tracked and gated to a given point in the ECG.
[0516] Reference is now made to FIG. 5, which is a schematic
illustration of a video stream of a subject's heart being (a) gated
51 to a phase of a physiological cycle (as described with reference
to FIG. 3), and (b) image tracked 52 (as described with reference
to FIG. 4), in accordance with an embodiment of the present
invention. The combined application of processes 51 and 52
typically results in a video stream that is stabilized with respect
to changes in the shape as well as the location of the organ(s)
being imaged.
[0517] Typically, when using the combined application of gating and
image tracking as in the sequence shown in FIG. 5, the
aforementioned smoothening or gap filling in the transformations
among selected image frames is performed on the output of the
gating and the image tracking (i.e., on the output of FIG. 5). In
such a case, each individual image frame which is an output of the
gating serves as an input for image tracking. After going through
both gating and image tracking, each individual frame becomes both
gated and image tracked, and the gap filling is performed on the
transformations between successive gated-and-image-tracked
frames.
[0518] It is noted that, as described, the scope of the present
invention also includes performing image tracking prior to
performing gating (configuration not shown in the figures). In this
case, the smoothening algorithms described herein are generally
applied to the output of the gating.
[0519] In some embodiments, a path for passing tools into desired
locations in the heart and/or coronary blood vessels is generated.
In some embodiments, such a path is also displayed.
[0520] In some embodiments, stabilized road mapping is applied to
cyclically-moving organs such as the coronary blood vessels, the
pulmonary vessels, the aorta, and/or to the heart itself. Road
mapping is typically helpful in reducing radiation time and/or the
amount of contrast agent being used to facilitate medical
procedures. Road mapping is commonly used in catheterization
procedures in organs that can typically remain motionless
throughout the procedure, such as blood vessels in the limbs. One
embodiment of road mapping is named Digital Subtraction Angiography
(DSA).
[0521] The use of road mapping is typically difficult with
conventional, constantly moving cardiac images, because the
historical roadmap and the displayed images are typically not
aligned with one another most of the time. Thus, road mapping is
typically not used in procedures performed on moving organs, such
as coronary interventions.
[0522] In some embodiments of the current invention, a historical
roadmap which was generated in the same phase of the cardiac cycle
to which the displayed, stabilized video stream is gated and from
the same viewing angle, is displayed as a background to the
real-time, stabilized video stream. (In some embodiments, the
aforementioned use of image tracking is also applied, for example,
in order to compensate for the effect of the respiratory cycle.)
The roadmapping typically generates an image of the coronary
vessels highlighted with a contrast agent. Consequently, the
real-time image of tools inserted through such vessels is typically
viewed as superimposed on the roadmap of those same vessels at the
same gated phase in the cardiac cycle. In some embodiments, by
generating a stabilized roadmap, manipulation of tools is
facilitated, and/or cumulative radiation throughout the procedure
is reduced, and/or the cumulative amount of contrast agent injected
throughout the procedure is smaller.
[0523] Typically the contrast agent is injected into a space within
the subject's cardiovascular system, for example, a chamber of the
subject's heart, a coronary blood vessel, and/or the subject's
aorta.
[0524] In some embodiments, using roadmapping facilitates the
direct stenting of the subject's coronary arteries, without
requiring a prior step of pre-dilatation. In such embodiments, the
roadmap typically improves the ability to place the stent
accurately and thus reduces the need to inflate a balloon which
does not carry a stent prior to the deployment of the stent itself.
That, in turn, typically reduces procedure time and/or cost.
[0525] In some embodiments, direct stenting as described herein is
capable of reducing the risk of embolization which may otherwise be
created if pre-dilatation is performed at a slightly different
location from that of the subsequent deployment of the stent. If
such a difference in location exists, then the occluding substance
or tissue that is being inflated and fragmented by a pre-dilatation
balloon may not be subsequently kept in place by the stent, and
thus embolization might occur.
[0526] Generation of the aforementioned roadmap is typically
benefited by knowledge by the system of when contrast agent is
being injected. In some embodiments, the injection of contrast
agent for highlighting the vessels is sensed, for the purpose of
generating the aforementioned roadmap, via an electrical signal
indicating the activation of the injection sub-system.
Alternatively or additionally, the injection of contrast agent for
highlighting the vessels is identified by means of image
processing. Further alternatively or additionally, the injection of
contrast agent for highlighting the vessels is identified by means
of analyzing changes in the image (such as via a histogram) of the
region at the distal end of the catheter from which the contrast
agent typically comes out (such as a guiding catheter in the case
of coronary road mapping). Changes in the image include a
relatively abrupt change in the color and/or grayscale level
(darkness) of a relatively large number and/or portion of image
pixels, or the appearance of vessel-like features in the image,
etc., or any combination thereof. It is noted that by assessing a
change in the darkness level to identify the time of injection of
the contrast agent, the control unit may identify a darker area of
the image or a lighter area of the image, depending on whether the
contrast agent is represented as dark or light. It is additionally
noted that whereas specifically assessing the region at the distal
end of the catheter typically enhances signal to noise (because
this region is most likely to show an abrupt change), the scope of
the present invention includes assessing all of the acquired image
data to identify the injection of the contrast agent.
[0527] In some embodiments, the road map being displayed in
conjunction with the stabilized video stream loops among multiple
images of different moments in the injection and dissipation
process of the contrast agent, wherein all of those images were
originally gated to a same phase in the cardiac cycle to which the
currently-displayed, stabilized video stream is gated.
[0528] In some embodiments, the road map being displayed in
conjunction with the stabilized video stream comprises an image of
the contrast agent itself. In some embodiments, the road map
comprises a synthesized background(s), enhancement(s), contour(s),
pattern(s), texture(s), shade(s) and/or color(s) that was created
based upon the visual information acquired from the injection
and/or dissipation of contrast agent, using computer graphics
and/or image processing techniques. In some embodiments, the gray
level of the road map is inversed, such that the road map appears
light against a darkened background.
[0529] In some embodiments, the summation or combination of two
road maps generated at different times in the procedure is
displayed. In some embodiments, a road map generated during a given
phase of a first cardiac cycle is summed with a road map generated
during a same phase of a second (typically immediately subsequent)
cardiac cycle, to create a combined road map that displays more
coronary vessels and/or displays coronary vessels with greater
clarity. In some embodiments, in the case of a total or partial
occlusion in a coronary vessel, the combined road map may comprise
the summation or combination of a roadmap created from an injection
of a contrast agent proximally to the occlusion, and a second road
map created from an injection of a contrast agent distally to the
occlusion, such as via a collateral vessel and/or in a retrograde
direction. In these embodiments, the roadmaps based on the
proximally- and distally-injected contrast agent are created in the
same phase of one or more cardiac cycles that are not necessarily
adjacent cardiac cycles.
[0530] In some embodiments, a three-dimensional road map is
constructed by combining two or more two-dimensional road maps
recorded from viewing angles that are typically different by 30
degrees or more. In some embodiments, the two two-dimensional road
maps (from which a three-dimensional road map is constructed) are
recorded concurrently from two different viewing angles by means of
a bi-plane fluoroscopy system. In some embodiments, a
three-dimensional road map is created from CT angiography images,
typically pre-procedural ones, and then correlated with the
real-time two-dimensional road map created from intra-procedural
angiography. In some embodiments, a three-dimensional road map is
constructed from two or more different images taken from the same
viewing angle but during different phases in the cardiac cycle.
[0531] In some embodiments, markings are applied upon the
stabilized images. For example, in the case of coronary
angioplasty, such markings may be applied to the longitudinal edges
of an occlusion, or to the region in which pre-dilatation was
performed, etc. In some embodiments, such markings are applied
manually with an input device such as a computer mouse, or by a
stylet in the case of a tablet computer. In some embodiments, such
markings are applied by hand on a touch screen. In some
embodiments, such markings appear to the viewer, throughout
subsequent changes in the viewing angle and/or zoom level or the
fluoroscopy/angiography system, as if they remain attached to the
blood vessels to which they refer. Such virtual attachment is
typically performed by means of image processing. In some
embodiments, the markings comprise a scale or a grid that is
generated on the stabilized image, to indicate to the physician the
dimensions of the image.
[0532] In some embodiments, on-line geometric and/or hemodynamic
measurements (e.g., size, flow, ejection fraction) are made and/or
displayed upon the stabilized images. "On-line" in this context
means that the measurements are made on the stabilized image
stream, as opposed to being made on frozen images extracted from an
image stream. For example, in the case of angioplasty, such
measurements, also known as Quantitative Coronary Analysis (QCA),
may include the length and inner diameter(s) of the occlusion and
be used as inputs for the selection of a balloon and/or a stent. In
some embodiments, the known size of an object seen in the
stabilized images, such as the outer diameter of an introducing
catheter or the size of a patch adhered to the patient's chest or
the distance between radiopaque markers on a tool, is used as a
reference in making such measurements. In some embodiments, the
orientation at which the medical tool is disposed within the
subject's body is determined, by determining an apparent distance
between radiopaque markers on a tool within the stabilized set of
image frames, with respect to the known distance of the markers
from each other. In some embodiments, the physical size
corresponding to an image pixel, as known from the imaging system,
is used as a reference (in which case no physical reference object
is required).
[0533] In some embodiments, the deployment of an endovascular
device, for example a balloon or a stent, is visually simulated
prior to actually being performed. For example, a virtual stent of
selected length and diameter may be visually placed and displayed,
within the stabilized image stream, as if it were situated at the
site of the occlusion. The suitability of the intended dimensions
as observed with the virtual stent can then be visually validated
by the physician prior to selecting and deploying the physical
stent. For some applications, multiple virtual stents, such as in
preparation for the stenting of a vascular bifurcation where a
physical stent will be required in each branch, are virtually
placed and matched with one another prior to their actual
deployment. In some embodiments, a virtual stent is placed in
proximity to a physical, already-deployed stent to verify that the
two match one another prior to deploying the second, physical
stent.
[0534] In some embodiments, the proper deployment of a virtual tool
is estimated by viewing it upon two stabilized images streams, each
corresponding to a different phase of the cardiac cycle. In some
embodiments, one such phase is diastolic while the second phase is
systolic. In some embodiments, in response to determining an
orientation at which a real medical tool (e.g., a catheter) is
disposed within the subject's body, the virtual tool is deployed at
a corresponding (e.g., identical) orientation.
[0535] In some embodiments, an operator manipulates an image of a
virtual tool deployed within the stabilized image stream, until the
virtual tool is of appropriate dimensions. A reference number of a
real tool that best corresponds to the dimensions of the virtual
stent is generated. (The reference number may be, for example, a
catalog number of a real tool.) Alternatively or additionally, the
dimensions of a real tool that corresponds to the dimensions of the
virtual tool are generated. In some embodiments, image processing
is applied to the simulated image of the virtual stent to determine
the curvature of a region in which the virtual stent is deployed
and dimensions of a real tool are generated that incorporate the
curvature of the region. In some embodiments, the orientation of
the region in which the virtual tool is deployed is determined in
order to generate the dimensions of a corresponding real tool.
[0536] In some embodiments, the proper deployment of an actual
stent is assessed by viewing the stent within two stabilized images
streams, each corresponding to a different phase of the cardiac
cycle. In some embodiments, one such phase is diastolic, while the
second phase is systolic.
[0537] In some embodiments, image processing techniques are applied
to enhance the image of (a) an endovascular device, and/or (b)
radiopaque markers which a device comprises, and/or (c) the walls
of the vessel in which the device is situated, within the
stabilized image stream. For example, the device may be a balloon
and/or a stent that is implanted in the subject's body or that is
transiently placed within the subject's body. Typically, such
enhancement is more easily generated in a stabilized video stream
in which the enhanced object is relatively stable, compared with in
a non-stabilized stream of images wherein the object being enhanced
is constantly shifting. In accordance with embodiments of the
invention, such enhancement may be performed on-line, within the
stabilized image stream. Consequently, in such embodiments, proper
deployment of the endovascular device being deployed may be
verified by the physician during a procedure.
[0538] In some embodiments, the stabilized image stream is used for
on-line measurement of the flow within a vessel, by measuring the
time it takes contrast agent to travel a known distance. In some
embodiments, the stabilized image stream is used for on-line
measurement of the saturation of contrast agent within targeted
tissue, such as heart muscle.
[0539] In some embodiments, additional images, such as images
produced by other modalities in a same or similar phase of the
cardiac cycle to which the stabilized video stream is gated, are
co-displayed. For some applications, such images are pre-operative,
intra-operative, or a combination of the two. Alternatively or
additionally, such images are two-dimensional or three-dimensional.
The modalities from which such images originate are used before or
during coronary procedures and include, without limitation,
fluoroscopy, CT, MRI, CT angiography, Trans Esophageal Echo (also
known as TEE), Trans Thoracic Echo (also known as TTE), Intra
Vascular Ultrasound (also known as IVUS), Intra Cardiac Ultrasound
(also known as Intra Cardiac Echo, or ICE), Optical Coherence
Tomography, Intra Vascular MRI, or any combination thereof. In some
embodiments, the co-display of such images together with the
aforementioned gated video stream is performed via fusion (e.g.,
image overlay), using image-to-image registration techniques. Such
a co-display typically provides the operator with enhanced clinical
information.
[0540] (Throughout the specification and the claims, the term
"overlay" and derivations thereof, should not be understood to
denote a particular order in which two or more images are combined.
Rather, it refers generally to the combination of two or more
images that are overlaid in space.)
[0541] In some embodiments, a first set of images are acquired by a
first imaging device from outside a portion of the subject's body,
for example by CT or using a fluoroscope. A second set of images
are acquired by a second imaging device from within the portion of
the subject's body, for example, using an intra-vascular ultrasound
probe, or an intra-vascular MRI probe. In some embodiments, the
first set of images are acquired before the second set of images
are acquired, and the two sets of images are registered to each
other. Alternatively, the first imaging device and the second
imaging device acquire the respective sets of image frames
simultaneously.
[0542] In some embodiments, images generated by an ultrasound probe
(such as IVUS) within a coronary vessel are used in conjunction
with the stabilized image stream (such as a stabilized fluoroscopic
image stream) in the following manner:
[0543] i. The fluoroscopic image stream is stabilized.
[0544] ii. An IVUS catheter is inserted to the site of an occlusion
under fluoroscopic imaging, to inspect endoluminal anatomy.
[0545] 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
fluoroscopy.
[0546] iv. The IVUS catheter is retrieved to make room for
balloon/stent deployment.
[0547] v. A catheter with a balloon and/or stent is inserted to the
site of the occlusion, under fluoroscopic imaging.
[0548] vi. The location of the distal tip of the catheter carrying
the balloon and/or stent is visually recognized (such as via
display coordinates).
[0549] vii. The IVUS images previously recorded at the same
location are displayed, together with the fluoroscopic images. In
some embodiments, the IVUS images are displayed in a separate
window (but on the same screen as the fluoroscopic images). In some
embodiments, the IVUS images are displayed on a separate screen. In
some embodiments, the IVUS images being displayed are
two-dimensional (also known as "slices"). In some embodiments, a
three-dimensional "tunnel-like" reconstruction of the IVUS images
of the vessel (or a section thereof) is displayed. In some
embodiments, the IVUS images are overlaid on the fluoroscopic
images. In some embodiments, the IVUS images are fused with the
fluoroscopic images.
[0550] viii. As a result, the balloon and/or stent may be deployed
based upon an on-line combination of real-time fluoroscopic images
and of IVUS images recorded earlier (for example, several minutes
earlier).
[0551] Although embodiments of the invention are described
primarily with reference to the heart, connecting vessels (e.g.,
aortic, pulmonary) and coronary blood vessels, embodiments of the
current invention are similarly applicable to any other organ
affected by periodic motion and/or periodic activity. An example
for the latter would be the brain.
[0552] Reference is now made to FIG. 6, which is a schematic
illustration of apparatus for synchronizing actuation of a medical
device with a physiological cycle, in accordance with an embodiment
of the present invention. Cyclically-moving organ 61 is imaged by
imaging device 62. Non-gated image frames are displayed on display
64. A cyclical physiological signal used for synchronization is
transmitted via line 68 to processor 63. Gated image frames are
displayed on display 66, which is connected to processor 63. In
some embodiments, gap filling is applied to the gated image frames.
In some embodiments, such images are also image tracked. Actuator
65 is actuated in a synchronized manner, with respect to the
synchronization signal transferred from processor 63 via a line 69.
Actuator 65, in turn, controls tool 67, which is applied to organ
61.
[0553] The scope of the present invention includes synchronizing,
with respect to a physiological cycle, the actuation and/or
movement of a medical device that performs a function on a portion
of a subject's body, without stabilizing images of the portion,
[0554] The scope of the present invention includes synchronizing,
with respect to a physiological cycle, the actuation and/or
movement of a medical device that performs a function on a portion
of a subject's body, in combination with stabilizing images of the
portion.
[0555] The scope of the present invention includes synchronizing,
with respect to a given phase of a physiological cycle, the
actuation and/or movement of a medical device that performs a
function on a portion of a subject's body, and stabilizing images
of the portion with respect to the same given phase of the
cycle.
[0556] FIGS. 7A-C and 8 through 12 are schematic illustrations of
apparatus for inflation of a balloon, such as for widening an
occlusion within a coronary blood vessel, in synchronization with
the patient's cardiac cycle, in accordance with respective
embodiments of the invention. In some embodiments, a stent, which
is positioned around the balloon, is expanded by inflating the
balloon. In some embodiments, the embodiments shown in FIGS. 7-12
are practiced in combination with stabilized imaging techniques
described hereinabove.
[0557] Typically, the placement and inflation of the balloon is
performed in a same selected specific phase of the cardiac cycle.
That typically leads to accuracy in the placement of the balloon at
a given location.
[0558] In cases where a single cardiac cycle is shorter than the
time it takes to easily or safely inflate a coronary balloon,
inflation in some embodiments is performed in an intermittent
(i.e., a stepwise) manner, in the course of a same selected phase
in multiple cardiac cycles (FIG. 7C).
[0559] In other embodiments, one or more segments of the inflation
of the balloon is performed continuously (i.e., not in
synchronization to the cardiac cycle) and one or more segments of
the inflation of the balloon is performed in the aforementioned
synchronized, stepwise manner. In one embodiment, synchronized
inflation until the balloon becomes fixed to the inner wall of the
lumen is followed by continuous inflation until the balloon is
inflated to a target diameter or volume. In another embodiment, the
balloon is inflated continuously till it reaches a given volume but
is not yet fixed to the inner walls of the lumen, followed by
synchronized inflation until it becomes fixed to the inner walls of
the lumen. In a third embodiment, the balloon is first inflated
continuously until it reaches a given volume, then inflated in a
synchronized manner until it becomes attached to the inner wall of
the lumen, and then inflated continuously again until it reaches a
desired diameter or volume.
[0560] In some embodiments, the aforementioned synchronized
placement and inflation are performed while viewing the
aforementioned stabilized image as described with reference to FIG.
1.
[0561] In some embodiments, the specific phase to which the
inflation of the balloon is synchronized is the end of the diastole
phase of the cardiac cycle. At the end-diastolic phase of the
cardiac cycle, the ventricles are typically at their fullest
volume. Furthermore, the inventors hypothesize that during the
end-diastolic phase of the cardiac cycle, the coronary arteries are
typically the most spread apart, and typically remain in that
situation for a fraction of a second. Such timing may further
assist in the correct apposition of a stent positioned upon the
balloon. Alternatively or additionally, the inflation of the
balloon is gated to a different phase of the subject's cardiac
cycle, for example, a mid-diastolic phase or a systolic phase.
[0562] Reference is now made to FIGS. 7A-B, which are schematic
illustrations of the actuation of inflation of a balloon 73 in
synchronization with a physiological cycle, in accordance with an
embodiment of the present invention. As shown in FIG. 7A, blood
vessel 71 is clogged by occluding substance or tissue 72. Balloon
73 is positioned at the occlusion and inflated by actuator 75 via a
tube. According to some embodiments of the current invention, a
synchronization signal derived from the patient's ECG is provided
via line 74. The ECG signal is used to trigger the increased
inflation pressure of balloon 73 in a stepwise manner, wherein each
step occurs in the same selected phase of the ECG cycle. The result
is sequence 76 (FIG. 7B), showing the steady, synchronized stepwise
inflation of the balloon, until the balloon is typically inflated
to the desired extent and at is the desired location.
[0563] In some embodiments, actuator 75 is connected to a typically
non-synchronized inflation device. In another embodiment, actuator
75 and the inflation device are integrated together into a single,
synchronized inflation device.
[0564] Reference is now made to FIG. 7C, which is a graph showing
the pressure 77 of the balloon as a function of time, in accordance
with an embodiment of the present invention.
[0565] Reference is now made to FIG. 8, which is a schematic
illustration of apparatus for facilitating the synchronized
inflation of a balloon 82, in accordance with an embodiment of the
present invention. The operator of the device actuates a handle 81
(such as via rotating), in order to inflate balloon 82. Handle 81,
by means of control circuit 83, commands driver 84. Driver 84 is
synchronized by a train of pulses 85 (which originates from the ECG
as explained previously), such that it produces a synchronous
output into a torque motor. The torque motor comprises a stator 86
and rotor 87. The torque motor rotates a lead screw 88. Stationary
drive nut 89 converts the rotational motion of lead screw 88 into
the linear motion of piston 810. The motion of piston 810 inside
cylinder 811 pushes the fluid contained within the distal portion
of cylinder 811 into inflation tube 812, and from there into
balloon 82.
[0566] FIGS. 9-11 are schematic illustrations of apparatus for
facilitating the synchronized inflation of a balloon, in accordance
with another embodiment of the present invention. Inflation device
91 and balloon catheter 92 are typically the same as those
conventionally used for non-synchronized balloon inflation. In some
embodiments, synchronization of balloon inflation to the patient's
cardiac cycle is enabled by an accumulator-modulator 93 that is
added and is typically connected between inflation device 91 and
balloon catheter 92. The output of inflation device 91, typically
in the form of inflation fluid, feeds accumulator-modulator 93. The
output of accumulator-modulator 93, typically in the form of
inflation fluid, feeds balloon catheter 92.
[0567] The purpose of accumulator-modulator 93 is to enable
intermittent balloon inflation that is performed, in whole or in
part, in a stepwise manner and in synchronization with the
patient's ECG signal. The modulator part of 93 is typically
responsible primarily for the synchronization of the inflation to
the ECG. The accumulator part of 93 is typically responsible
primarily for maintaining a continuous build-up of the inflation
pressure despite the inflation itself being (in whole or in part)
intermittent. (Without the accumulator, undesirable increases and
decreases in the inflation pressure may occur.)
[0568] FIG. 10 is a schematic illustration of an embodiment of
accumulator-modulator 93 described with respect to FIG. 9. The
accumulator unit comprises a loaded piston 101. The modulator unit
comprises valve 102, driver circuit 103 and internal power supply
104. Internal power supply 104 is optional, as an alternative to an
external power supply. Driver circuit 103 is fed by the ECG-derived
synchronization signal via line 107, and based on that signal
drives valve 102 to assume the open and closed positions. In an
embodiment, the accumulator-modulator receives its input, typically
in the form of inflation fluid, from an inflation device via inlet
105. The accumulator-modulator typically provides its output,
typically in the form of inflation fluid, to a balloon catheter via
outlet 106.
[0569] As noted above, the modulator unit of the
accumulator-modulator described with respect to FIG. 9 and FIG. 10
typically comprises a valve that opens and shuts in accordance with
the ECG-derived synchronization signal and through which the
inflation fluid traverses. Such a valve may comprise any known
implementation, including a check valve of any type (e.g., ball
check, duckbill, swing check, clapper, stop check), a leaf valve,
or any combination thereof.
[0570] FIG. 11 is a detailed schematic illustration of the
accumulator-modulator described with respect to FIG. 9 and FIG. 10,
in accordance with an embodiment of the present invention.
Inflation fluid traverses flexible tube 111 on its way towards the
outlet of the accumulator-modulator. Tube 111 changes
intermittently between being open and shut for the flow of such
fluid. Two arms 112, pivoting on axes 115, intermittently squeeze
and release tube 111. The activation of coil 113 causes arms 112 to
pull closer to one another for minimizing the magnetic field
reluctance, and thus squeeze tube 111 shut. When coil 113 is
deactivated, arms 112 (with the assistance of an optional recoil
spring 114) pull apart and cause tube 111 to open for the passage
of inflation fluid.
[0571] Reference is now made to FIG. 12, which is a schematic
illustration of apparatus for facilitating the synchronized
inflation of a balloon, the apparatus being built into an inflation
device, in accordance with a further embodiment of the present
invention. A pressure signal 125 is created by inflation mechanism
126. An ECG-derived synchronization signal 121 and pressure signal
125 are both fed into controller 122. A synchronized actuation
signal 123 is fed from controller 122 to valve modulator 124. The
output of valve modulator 124, typically in the form of inflation
fluid, is fed into a balloon catheter that is typically connected
distally to the inflation device. As a result, the balloon is
inflated gradually, in a stepwise manner, to a desired size.
[0572] Each of the aforementioned balloon inflation apparatuses and
methods, described with respect to FIGS. 7 through 12, may be
synchronized either to the patient's ECG signal, blood pressure
signal, displacement signal, vibration signal or to a different
signal corresponding to the patient's cardiac cycle, or to any
combination, derivation, extrapolation or manipulation thereof.
[0573] In some embodiments, the aforementioned balloon inflation
apparatuses and methods described with respect to FIGS. 7 through
12 apply not only to the placement and inflation of a balloon, but
also to the deployment of a stent which is positioned upon the
balloon. Typically, deploying a stent in a virtually stable
environment leads to greater accuracy in the placement of the stent
at a given location. In some embodiments, other medical tools which
are positioned upon the balloon are deployed via the inflation of
the balloon. For example, a valve, a graft, a septal-closure
device, and/or another medical tool may be deployed via the
inflation of the balloon.
[0574] In some embodiments, while causing the inflation of the
balloon to occur (in whole or in part) in a stepwise manner in
synchronization with the ECG signal, the aforementioned balloon
inflation apparatus and methods described with respect to FIGS. 7
through 12 provide the operator of the inflation device with
continuous force feedback during inflation. Thus, the operator of
the inflation device typically feels as if the balloon inflation
process is continuous even though that process, or parts thereof,
is in fact intermittent. In some embodiments, the apparatus
smoothens the force feedback with respect to the physiological
cycle to which the inflation is gated, so that the effect of the
stepwise inflation, on the force feedback to the operator, is
reduced.
[0575] Although embodiments of synchronizing the actuation, and/or
the movement of a tool to a physiological cycle, have been
described with respect to a balloon, the scope of the invention
includes applying these embodiments to the other medical tools
described herein.
[0576] FIGS. 13 through 15 disclose embodiments of the synchronized
application of a guide wire, such as for opening an occlusion in a
coronary blood vessel, in accordance with an embodiment of the
present invention. In some embodiments, application of the guide
wire is synchronized either to the patient's ECG signal, or to a
different signal corresponding to the patient's cardiac cycle, or
to any combination, derivation, extrapolation or manipulation
thereof.
[0577] Reference is now made to FIG. 13, which is a schematic
illustration of synchronization of the penetration of an occlusion
132 of a blood vessel 131 with cyclic movement of the blood vessel,
in accordance with an embodiment of the present invention. In the
case of a total or near-total occlusion, such penetration typically
precedes the inflation of a balloon and/or the placement of a
stent. Wire 133 penetrates the occlusion in a synchronized,
stepwise manner. An actuator 135, synchronized by signal 134 coming
from the patient's ECG, is used to generate the stepwise forward
motion as seen in schematic sequence 136. Typically, such
synchronized forward motion of the wire 133 enables these
embodiments of the current invention to reduce the probability of
perforation or dissection of blood vessel 131 by the guide wire.
Conversely, in conventional procedures, such perforation or
dissection is known to occur, typically due to pushing the wire at
a phase in the cardiac cycle where the wire actually points at the
wall of the vessel and not towards the desired point of entry on
the surface of the occlusion.
[0578] In some embodiments, synchronization is made to a phase in
the cardiac cycle when the coronary arteries are typically
maximally inflated and thus with the largest cross section. Such
timing may assist in opening the occlusion.
[0579] In some embodiments, the operator feels as if he or she
pushes the wire continuously, while the actuator causes the wire to
be pushed intermittently, in synchronization with the ECG
signal.
[0580] In some embodiments, the aforementioned synchronization is
applied to a tool used for widening or opening occlusions, where
the tool is not a guide wire. In some embodiments, synchronization
is applied to the tool's motion within the occlusion. In some
embodiments, an occlusion-opening tool, for example a tool having
jackhammer-like functionality, is moved toward the occlusion during
the given phase of respective cycles. Typically, after the tool is
moved toward the occlusion at the given phase of a first cycle and
before the tool is moved toward the occlusion at the given phase of
a subsequent cycle the tool is retracted from the occlusion. In
another embodiment, synchronization is used to control the release
of energy, for example, ultrasonic energy, aimed at widening or
opening the occlusion.
[0581] Reference is now made to FIG. 14, which is a schematic
illustration of a modulator for synchronizing the penetration of an
occlusion of a blood vessel by a wire 141 with the cyclic movement
of the blood vessel, in accordance with an embodiment of the
present invention. The modulator generates stepwise motion of wire
141. The modulator disclosed herein is an embodiment based on a
self-locking clamp 143 driven by a voice coil incorporating a coil
plunger 145 and a permanent magnet stator 146. A return spring 142
is also incorporated. Other modulators capable of generating
periodic motion that are known in the art include, but are not
limited to, those based on roller wheels, grippers, or
piezoelectric or magnetostrictive effects. The modulator is
typically housed in shell or housing 144. Wire 141 can be placed
into the modulator at any desired position along the wire, for
example after the interventional cardiologist has already pushed
the wire all the way to the occlusion.
[0582] In some embodiments, similar modulating heads yield
rotational motion of the wire by adding a torque generator to the
modulator.
[0583] Reference is now made to FIG. 15, which is a schematic
illustration of a handheld actuator that comprises the modulator
described with respect to FIG. 14, in accordance with an embodiment
of the present invention. Electronic circuit 152 conveys a driving
signal to modulator 153, in the manner already described with
respect to FIG. 14. Control stick 151 controls the motion of guide
wire 155. For example, when the operator pushes stick 151 forward,
or activates a trigger, the actuator conveys a corresponding train
of pulses to modulator 153. These pulses are synchronized via line
154 to the reference signal. The pulse train, when delivered to the
modulator, creates the forward motion of the guide wire in a
synchronized stepwise manner. Typically, the harder operator pushes
control stick 151, the more intense are the pulses, hence wire 155
will move forward at a higher pace. By pulling stick 151 backwards,
the guide wire will move correspondingly backwards. In some
embodiments, the force feedback provided to control stick 151 is
spring loaded. In some embodiments, a force feedback that bears
greater resemblance to the original force feedback of wire 155 is
generated. For example, force feedback that does not vary with
respect to the cyclic activity of the blood vessel, or force
feedback that is smoothened with respect to the movement of the
blood vessel, may be generated.
[0584] In some embodiments, the operator exerts force on guide wire
155 directly, and not indirectly via control stick 151 as is
described above.
[0585] In some embodiments, the actuator provides custom force
feedback which typically increases its user-friendliness by
providing the operator with a more familiar feel. In some
embodiments, the actuator (and specifically the control stick)
replicates the tactile feedback of specific medical tools, thus
increasing its utility to the operator. In some embodiments, a
digital library of tool-specific force feedbacks is connected to
the actuator. In some embodiments, the force feedback specific to
each tool is selected by the operator. In some embodiments, the
force feedback specific to each tool is selected automatically,
with the actuator identifying the tool (such as via a specific
code).
[0586] In some embodiments, the aforementioned actuator controls
the application of: [0587] linear motion, [0588] angular motion
(e.g., for the purpose of turning the tip of the penetrating device
and, for example, for leading a drill through an occlusion in a
coronary blood vessel synchronized with the cardiac cycle), [0589]
energy (e.g., for radio frequency ablation synchronized with the
cardiac cycle, or for percutaneous myocardial revascularization via
the application of laser in synchronization with the cardiac
cycle), [0590] substance delivery (e.g., gene therapy for cardiac
revascularization synchronized with the cardiac cycle), or [0591]
pressure, such as for inflating a balloon and/or a stent [0592] any
combination thereof.
[0593] In some embodiments, the aforementioned actuator comprises
re-usable elements, restricted-reuse elements, single-use elements,
or any combination thereof. In some embodiments, the actuator, or
elements thereof, are usable only for a specific time period and/or
a specific number of uses following their initial activation. In
some embodiments, the time period and/or number of uses are coded
in a memory element (such as a memory chip) incorporated into the
actuator.
[0594] Reference is now made to FIG. 16, which is a schematic
illustration of the stepwise transluminal placement of a coronary
bypass graft 163 in a coronary blood vessel 161 in order to bypass
an occlusion 162, in accordance with an embodiment of the present
invention. In the prior art, such an implantation is typically
performed during open heart surgery. In such surgery, a bypass is
implanted between the proximal and distal sides of a major
impairment (such as a total occlusion) in a blood vessel.
Embodiments of the current invention, by providing a full or
partial virtual stabilization as previously explained, make it
possible to connect the proximal and distal sides of impairment 162
without open surgery. Based on a combination of the stabilized
image of blood vessel 161 and the synchronous activation (based
upon signal 164 and by means of actuator 165) of the tool(s)
delivering and placing the graft, the two sides of the impairment
are connected transluminally. Typically, images generated from two
separate views, sequentially or concurrently (such as those
provided concurrently by a bi-plane fluoroscopy system), are used.
Such views typically differ from one another by at least 30
degrees, and in some embodiments they are perpendicular. In some
embodiments, the graft is a biological graft. Alternatively, the
graft is a synthetic graft.
[0595] In some embodiments, the aforementioned modulator,
modulator-accumulator and/or actuator are not hand held. In some
embodiments, the aforementioned modulator, modulator-accumulator or
actuator are connected to or operated by a medical robot. In some
embodiments, the aforementioned modulator, modulator-accumulator
and/or actuator are operated in a remote manner via a
communications network (e.g., tele-operation).
[0596] For some applications, the aforementioned techniques are
applied to an organ that does not move cyclically, but is
cyclically active (such as the brain).
[0597] In some embodiments, the synchronized tools disclosed by the
current invention are connected to, or operated by, a medical
robot.
[0598] The scope of the present invention includes using the
techniques of synchronized actuation of a tool, as described
hereinabove, for applications other than those described in detail
hereinabove. In general, the techniques can be used in combination
with the techniques described hereinabove, for stabilized imaging
of a cyclically moving organ. In some embodiments, movement of a
tool in a given direction or along a desired pattern is
synchronized with a physiological cycle. Typically, the tool is
moved in the given direction at a given phase of respective
physiological cycles without moving the tool in the opposite
direction to the given direction, between movements of the tool in
the given direction.
[0599] In some embodiments, a tool is moved in a given direction by
moving the center of the tool. In some embodiments, at a given
phase of respective cycles of a physiological cycle, a tool is
actuated either to perform a function, or to move. For some
applications, at a given phase of a single cycle of a physiological
cycle, a tool is actuated to mechanically perform a function with
respect to a portion of the subject's body that moves as a result
of the cycle. For example, the techniques described hereinabove can
be applied to the following additional procedures: [0600]
Percutaneous placement, replacement or repair of a cardiac valve
such as an aortic valve, a mitral valve, a pulmonary valve, or a
tricuspid valve. The percutaneous approach may be transvascular or
through an incision (such as transapical). It is important to
deploy the valve accurately, relative to the surrounding anatomy.
Doing so in a beating heart or vessel is often difficult. In
accordance with some embodiments of the current invention, a tool
carrying a valve is led to, and/or positioned at, and/or actuated
to deploy the valve at a desired anatomical location in
synchronization with a selected phase of the cardiac cycle. In some
embodiments, the selected phase is when the corresponding anatomy
is at a peak dimension. In some embodiments, the selected phase of
the cycle is when the corresponding anatomy remains stable, or
relatively stable, for the longest duration. In some embodiments,
the tool and the anatomy are viewed in an image stream that is
stabilized at a same selected phase of the cardiac cycle. In some
embodiments, the selected phase at which the tool is moved,
positioned, activated or applied is the same selected phase at
which an observed image stream is stabilized. In some embodiments,
the valve is deployed by expanding the valve at the selected phase
during a single cycle. Alternatively, the valve is deployed by
expanding the valve in a stepwise manner, at the selected phase,
during more than one cycle. [0601] Catheterization of pulmonary
arteries, applying the tools and techniques (e.g., guide wire,
balloon, stent, occlusion-opening devices) previously described in
the context of the coronary arteries. In some embodiments, such a
procedure is performed in conjunction with stabilized imaging as
described hereinabove. In another embodiment, such a procedure is
performed not in conjunction with stabilized imaging, but yet in
synchronization with the cardiac cycle, so as to achieve improved
deployment of a balloon or a stent, or better penetration of an
occlusion. [0602] Closure of holes in the septal wall, such as
Patent Foramen Ovale (PFO) and Atrial Septal Defect (ASD), within
the cyclically-moving heart. With embodiments of the current
invention, a carrier carrying a closure device is led to, and
positioned at, a desired anatomical location (such as the site of
the hole in the septum) while both carrier and heart anatomy are
viewed in an image stream that is typically stabilized at a
selected same phase in the cardiac cycle. Next, the closure device
is deployed (including its assembly, expansion and/or release from
the carrier) at the desired anatomical location in a selected phase
of the cardiac cycle. Such a selected phase is typically the same
as the phase selected for the stabilization of the image stream. In
some embodiments, the closure device is deployed by expanding the
closure device at the selected phase during a single cycle.
Alternatively, the closure device is deployed by expanding the
closure device in a stepwise manner, at the selected phase, during
more than one cycle. [0603] Placement of a stent graft within the
cyclically-moving aorta to treat abdominal aortic aneurysms. In
accordance with embodiments of the current invention, a carrier
carrying a stent graft is led to, and positioned at, a desired
anatomical location (such as the site of the aneurysm) while both
carrier and aortic anatomy are viewed in an image stream that is
typically stabilized at a selected same phase in the cardiac cycle.
Next, the stent graft is deployed (including its assembly,
expansion and/or release from the carrier) at the desired
anatomical location in a selected phase of the cardiac cycle. Such
selected phase is typically the same as the phase selected for the
stabilization of the image stream. In other embodiments of the
current invention, the graft is deployed at the desired anatomical
location in a selected phase of the cardiac cycle (such as when the
corresponding section of the target vessel is at its peak
dimensions), without observing stabilized imaging. In some
embodiments, the stent is a self-expansible stent. [0604] Localized
energy application to a tissue, such as within the heart (e.g.,
cardiac ablation performed by means of radio frequency ablation,
cryoablation, laser, electrocautery, or ultrasound to address
cardiac arrhythmia). In some embodiments, the current invention
facilitates the ablation of endocardial tissue in a desired
pattern, such as a continuous line or a series of lines, for
example, to apply a Maze procedure to the tissue. In some
embodiments, movement of the ablation tool is performed in
synchronization with a selected phase in the cardiac cycle. In some
embodiments, delivery of energy is performed in synchronization
with a selected phase in the cardiac cycle. In some embodiments,
the endocardial tissue is observed via an image stream stabilized
at a selected phase in the cardiac cycle, and movement and/or
activation of an ablation (or other) tool is applied at the same
selected phase in the course of a plurality of cardiac cycles.
[0605] Percutaneous myocardial revascularization, such as via
creating holes in the heart muscle in a desired pattern and by
means of an energy delivery or mechanical penetration tool. In some
embodiments, movement of the tool is performed in synchronization
with a selected phase in the cardiac cycle. In some embodiments,
the tool is actuated (such as to deliver energy or drill a hole) in
synchronization with a selected phase in the cardiac cycle. In some
embodiments, the endocardial tissue is observed via an image stream
stabilized at a selected phase in the cardiac cycle, and movement
and/or activation of the tool is applied at the same selected phase
in the course of a plurality of cardiac cycles. [0606] Delivering
any material or substance, such as, for example, gene therapy or
stem cells to specific locations in the heart muscle. In some
embodiments, the current invention facilitates the injection of a
substance into the heart muscle in a desired pattern, such as a
series of points spread across a surface area. In some embodiments,
movement of the tool is performed in synchronization with a
selected phase in the cardiac cycle. In some embodiments, delivery
of the substance is performed in synchronization with a selected
phase in the cardiac cycle. In some embodiments, the endocardial
tissue is observed via an image stream stabilized at a selected
phase in the cardiac cycle, and movement of the tool and/or
delivery of the substance is applied at the same selected phase in
the course of a plurality of cardiac cycles. [0607] Suturing tissue
in a cyclically-moving organ, such as in a bypass or a valve or a
graft. In some embodiments, movement of the suturing tool is
performed in synchronization with a selected phase in the cardiac
cycle. In some embodiments, suturing is performed in
synchronization with a selected phase in the cardiac cycle. In some
embodiments, the endocardial tissue is observed via an image stream
stabilized at a selected phase in the cardiac cycle, and movement
of the tool and/or suturing is applied at the same selected phase
in the course of a plurality of cardiac cycles. [0608] Trans
Thoracic Needle Aspiration (TTNA), such as when a cyclically-moving
lesion within the lungs needs to be biopsied (and while avoiding
mistaken penetration of life-critical organs). With embodiments of
the current invention, an aspiration needle is led to, and
positioned at, a desired anatomical location in the thorax (such as
a lung lesion) while both the tool and thoracic anatomy are viewed
in an image stream (such as CT images) that is typically stabilized
at a selected same phase in the respiratory and/or cardiac cycle.
Next, aspiration is performed at the desired anatomical location in
a selected phase of the cardiac and/or respiratory cycle. The
selected phase is typically the same as the phase selected for the
stabilization of the image stream. [0609] Trans Bronchial Needle
Aspiration (TBNA) such as when a cyclically-moving lesion within
the lungs needs to be biopsied (and while avoiding mistaken
penetration of life-critical organs). [0610] Neural stimulation in
the brain with its activation gated with the EEG signal. [0611]
Attaching or placing a tool at a desired location, on or within a
cyclically-moving organ. [0612] Moving or directing a tool to a
desired location, on or within a cyclically-moving organ. [0613] Or
any combination thereof.
[0614] 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.
* * * * *