U.S. patent application number 10/892348 was filed with the patent office on 2005-01-13 for system and method for three-dimensional reconstruction of an artery.
This patent application is currently assigned to Paieon, Inc.. Invention is credited to Assis, Tsuriel, Carmieli, Ran, Evron, Rami.
Application Number | 20050008210 10/892348 |
Document ID | / |
Family ID | 26323946 |
Filed Date | 2005-01-13 |
United States Patent
Application |
20050008210 |
Kind Code |
A1 |
Evron, Rami ; et
al. |
January 13, 2005 |
System and method for three-dimensional reconstruction of an
artery
Abstract
A method and system for imaging an artery contained in an
arterial tree. A microprocessor generates a three-dimensional
reconstruction of the arterial tree from two or more angiographic
images obtained from different perspectives. The orientation of the
axis of the artery in the arterial tree is then determined, and a
perspective of the artery perpendicular to the axis of the artery
is determined. A three dimensional reconstruction of the artery
from angiographic images obtained from the determined perspective
is then generated.
Inventors: |
Evron, Rami; (Tel Aviv,
IL) ; Assis, Tsuriel; (Rehovot, IL) ;
Carmieli, Ran; (Rinatia, IL) |
Correspondence
Address: |
BROWDY AND NEIMARK, P.L.L.C.
624 NINTH STREET, NW
SUITE 300
WASHINGTON
DC
20001-5303
US
|
Assignee: |
Paieon, Inc.
New York
NY
|
Family ID: |
26323946 |
Appl. No.: |
10/892348 |
Filed: |
July 16, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10892348 |
Jul 16, 2004 |
|
|
|
09662325 |
Sep 14, 2000 |
|
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Current U.S.
Class: |
382/130 ;
382/131 |
Current CPC
Class: |
G06T 2219/2016 20130101;
G06T 2211/404 20130101; Y10S 128/922 20130101; A61B 6/504 20130101;
G06T 19/20 20130101 |
Class at
Publication: |
382/130 ;
382/131 |
International
Class: |
G06K 009/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 9, 2000 |
IL |
136050 |
Claims
1. (canceled)
2. The system of claim 20 wherein the microprocessor is further
configured to display on the display device any one or more of: an
angiographic image, the three dimensional reconstruction of the
artery and metrological measurements on the three dimensional
reconstruction of the artery.
3. (canceled)
4. The system of claim 20 wherein the microprocessor is further
configured to make measurements on the reconstruction of the
artery.
5. The system according to claim 20 wherein the microprocessor is
further configured to manipulate an image on the display.
6. (canceled)
7. The system of claim 2 wherein the microprocessor is configured
to display on the display a view of the three-dimensional
reconstruction of the artery from a selected perspective, such as a
cross sectional perspective.
8-9. (canceled)
10. The method of claim 27 further comprising displaying any one or
more of an angiographic image, the three-dimensional reconstruction
of the artery and metrological measurements on the three
dimensional reconstruction of the artery.
11. The method of claim 27 further comprising performing
metrological measurements on the three-dimensional reconstruction
of the artery.
12. The method according to claim 10 further comprising
manipulating an image on the display.
13. (canceled)
14. The method of claim 10 further comprising displaying a view of
the three-dimensional reconstruction of the artery from a selected
perspective, such as a cross sectional perspective.
15-17. (canceled)
18. The method according to claim 27 wherein the arterial tree is
selected from the group comprising the coronary arterial tree, the
renal arterial tree, the pulmonary arterial tree, the cerebral
arterial tree, and the hepatic arterial tree.
19. The method according to claim 29 wherein the stenotic artery
has a lumen, the lumen has a cross-section of maximal narrowing,
the cross-section of maximal narrowing has a fraction occluded by
plaque, and determining the severity of the stenosis includes
determining the fraction of the cross-section of maximal narrowing
occluded by plaque.
20. A system for imaging an artery contained in an arterial tree,
the system comprising: a processor adapted for coupling to a
display device for displaying on said display device at least two
angiographic images of the arterial tree from different
perspectives; said processor being responsive to an artery of
interest in the displayed angiographic images for generating a
three dimensional reconstruction of the artery of interest from at
least one of the displayed angiographic images.
21. The system according to claim 4, wherein the artery of interest
is a stenotic artery and the metrological measurements include a
severity and length of stenosis of the artery.
22. The system according to claim 20, wherein the processor is
adapted to be coupled to a manual selection device for selecting
the artery of interest manually.
23. The system according to claim 20, wherein the processor is
responsive to an additional perspective being selected for updating
the reconstruction of the artery of interest for display by the
display device.
24. The system according to claim 20, wherein: the processor is
responsive to one or more manual operator commands for image
processing the reconstructed artery for display on the display
device.
25. A system for imaging an artery contained in an arterial tree,
the system comprising: a display device for displaying at least two
angiographic images of the arterial tree from different
perspectives; a selection device for selecting an artery of
interest in the displayed angiographic images; a processor coupled
to the display device and to the selection device for generating a
three dimensional reconstruction of the artery of interest from at
least one of the displayed angiographic images.
26. The system according to claim 25, wherein the selection device
is a manual operator control.
27. A method for imaging an artery contained in an arterial tree,
the method comprising: displaying at least two angiographic images
of the arterial tree from different perspectives; selecting an
artery of interest in the displayed angiographic images; generating
a three dimensional reconstruction of the artery of interest from
at least one of the displayed angiographic images; and displaying
the three dimensional reconstruction of the artery of interest.
28. The method according to claim 27, wherein the artery of
interest is a stenotic artery.
29. The method according to claim 28, the method further comprising
analyzing the three-dimensional reconstruction of the artery to
determine a severity and length of stenosis of the artery.
30. A program storage device readable by machine, tangibly
embodying a program of instructions executable by the machine to
perform method steps for imaging an artery contained in an arterial
tree, the method comprising: displaying at least two angiographic
images of the arterial tree from different perspectives; selecting
an artery of interest in the displayed angiographic images;
generating a three dimensional reconstruction of the artery of
interest from at least one of the displayed angiographic images;
and displaying the three dimensional reconstruction of the artery
of interest.
31. A computer program product comprising a computer useable medium
having computer readable program code embodied therein for imaging
an artery contained in an arterial tree, the computer program
product comprising: computer readable program code for causing the
computer to display at least two angiographic images of the
arterial tree from different perspectives; computer readable
program code for causing the computer to select an artery of
interest in the displayed angiographic images; computer readable
program code for causing the computer to generate a three
dimensional reconstruction of the artery of interest from at least
one of the displayed angiographic images; and computer readable
program code for causing the computer to display the three
dimensional reconstruction of the artery of interest.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to medical devices, and more
specifically to such devices for use in angiography.
BACKGROUND OF THE INVENTION
[0002] Stenosis of an artery refers to narrowing of the artery
lumen due to plaque formation on the interior wall of the artery.
The severity of the stenosis is the fraction of the cross-sectional
area of the lumen that is occluded by plaque. Since narrowing is
often asymmetrical about the axis of the artery, in order to assess
the severity of a stenosis, it is necessary to obtain at least two,
and preferably more, images perpendicular to the artery axis from
orthogonal perspectives.
[0003] In angiography, the arterial lumen is filled with a
radio-opaque substance and X-ray images of the arterial tree are
obtained from different perspectives. Selection of these
perspectives is partly arbitrary and partly a process of trial and
error once a stenosis has been observed. However, the overall
number of images that can be obtained is limited by time, safety
and cost. Usually four to seven projections for the left coronary
arterial system and two to four for the right coronary artery are
obtained. The operator assesses the severity of the stenosis either
on the basis of visual examination of the images or by computer
analysis of a single image. Since these projections are in general
not perpendicular to the arterial axis, estimation of stenosis
severity and its length from these images is usually not
accurate.
SUMMARY OF THE INVENTION
[0004] It is therefore an object of the invention to provide a more
accurate process and system for computer reconstruction of an
artery from discrete images of the artery.
[0005] Such an objective is realized in accordance with a first
aspect of the invention by a system comprising means for obtaining
two-dimensional angiographic images of arteries, and a
microprocessor for processing the images. The images may be
obtained, for example, by X-ray angiography or by ultrasound.
[0006] In accordance with a second aspect of the invention, there
is provided a process for obtaining two or more angiographic images
of an arterial tree. The images preferably include two images taken
from perpendicular perspectives. In the case of the coronary
arterial tree, all images are preferably obtained when the heart is
in the same state, for example, diastole. A three dimensional (3D)
reconstruction of the arterial tree is generated by the
microprocessor from the images by methods known in the art. Methods
of generating a 3D reconstruction of an arterial tree from discrete
images can be found, for example, in anyone of the following
references all of which are included herein in their entirety by
reference: Faugeras, O. D., Mass. Inst. Tech. 1993; Garreau, et
al., IEEE Trans Med Imag 10(2):122-131; Grosskopf, S, Dissertation,
Technical University of Berlin, 1994; and Hildebrand and Grosskopf,
in Proc. Comp. Assisted Radiology CAR 95 conference, Berlin
Springer, pp 201-207, 1995. The arterial tree may be, for example,
the coronary arterial tree, the renal arterial tree, the pulmonary
arterial tree, the cerebral arterial tree, or the hepatic arterial
tree.
[0007] The 3D reconstructed arterial tree may be represented on a
display screen using pseudo 3D effects such as directional lighting
and shading. In a preferred embodiment, the reconstructed tree is
presented as a stereoscopic pair of images to be viewed by the
operator using a stereoscopic viewer. The reconstruction may be
manipulated on the screen by the operator, allowing him, for
example, to zoom in on a specific region or to rotate the
reconstructed artery on the screen to obtain a desired
perspective.
[0008] An artery, for example, a stenotic or aneurotic artery
present in any of the obtained angiographic images may be detected
by analysis of the images by the microprocessor or by visual
examination of the images by the operator. The microprocessor
determines the orientation of the axis of the artery in the 3D
reconstruction of the arterial tree. The microprocessor then
calculates two or more perspectives of the artery perpendicular to
the arterial axis. Preferably, two orthogonal perspectives are
determined. If images of the selected artery have not already been
obtained approximately from the calculated perspectives, the
operator obtains angiographic images of the artery from these
perspectives and the microprocessor then constructs a 3D
reconstruction of the artery from the angiographic images by
methods known in the art. The invention thus allows an operator to
obtain images of the artery from orthogonal perspectives more
rapidly than is possible by prior art methods of trial and error.
This allows a smaller radio-opaque dosage to the patient and a
reduced exposure of the patient and the is operator to X-rays.
[0009] The microprocessor may apply meteorological tools to the
reconstructed artery. In the case of a stenotic artery, the
microprocessor may provide accurate quantitative assessment of the
extent and length of the stenosis. The severity of a stenosis may
be described quantitatively, for example, by the fraction of the
arterial lumen occupied by plaque.
[0010] The 3D reconstructed artery may be represented on a display
screen using pseudo 3D effects such as directional lighting and
shading. In a preferred embodiment, the reconstructed artery is
presented as a stereoscopic pair of images to be viewed by the
operator using a stereoscopic viewer. The reconstruction may be
presented to the operator embedded in the 3D reconstruction of the
entire arterial tree. The reconstruction may be manipulated on the
screen by the operator, allowing him, for example, to zoom in on a
specific region or to rotate the reconstructed artery on the screen
to obtain a desired perspective of the stenosis including a
perspective showing maximal narrowing or a cross section of the
artery.
[0011] Thus, in its first aspect the invention provides a system
for imaging an artery contained in an arterial tree, the artery
having an axis, the system comprising:
[0012] a a microprocessor configured to
[0013] aa generate a three-dimensional reconstruction of the
arterial tree from two or more angiographic images of the arterial
tree obtained from different perspectives;
[0014] ab determine an orientation of the axis of the artery in the
arterial tree;
[0015] ac determine from the three-dimensional reconstruction of
the arterial tree at least one perspective of the artery
perpendicular to the axis of the artery; and
[0016] ad generate a three dimensional reconstruction of the artery
from angiographic images obtained essentially from the determined
at least one perspective.
[0017] In its second aspect, the invention provides a method for
imaging an artery contained in an arterial tree, the artery having
an axis, the method comprising the steps of:
[0018] a generating a three-dimensional reconstruction of the
arterial tree from two or more angiographic images of the arterial
tree obtained from different perspectives;
[0019] b determining an orientation of the axis of the artery in
the arterial tree;
[0020] c determining from the three-dimensional reconstruction of
the arterial tree at least one perspective of the artery
perpendicular to the axis of the artery; and
[0021] d generating a three dimensional reconstruction of the
artery from angiographic images obtained essentially from the
determined at least one perspective.
[0022] In its third aspect, the invention provides a method for
diagnosing stenosis in an arterial tree in an individual, the
method comprising the steps of:
[0023] a generating a three-dimensional reconstruction of the
arterial tree from two or more angiographic images of the arterial
tree obtained from different perspectives;
[0024] b detecting in the three-dimensional reconstruction of the
arterial tree a stenotic artery, the stenotic artery having an
axis;
[0025] c determining an orientation of the axis of the stenotic
artery;
[0026] d determining from the three-dimensional reconstruction of
the arterial tree at least one perspective of the stenotic artery
perpendicular to the axis of the artery;
[0027] e generating a three dimensional reconstruction of the
artery from angiographic images obtained essentially from the
determined at least one perspective; and
[0028] f analyzing the three-dimensional reconstruction of the
artery.
[0029] In its fourth aspect, the invention provides a program
storage device readable by machine, tangibly embodying a program of
instructions executable by the machine to perform method steps for
imaging an artery contained in an arterial tree, the artery having
an axis, said method steps comprising:
[0030] a generating a three-dimensional reconstruction of the
arterial tree from two or more angiographic images of the arterial
tree obtained from different perspectives;
[0031] b determining an orientation of the axis of the artery in
the arterial tree;
[0032] c determining from the three-dimensional reconstruction of
the arterial tree at least one perspective of the artery
perpendicular to the axis of the artery; and
[0033] d generating a three dimensional reconstruction of the
artery from angiographic images obtained essentially from the
determined at least one perspective.
[0034] In its fifth aspect, the invention provides a computer
program product comprising a computer useable medium having
computer readable program code embodied therein for imaging an
artery contained in an arterial tree, the artery having an axis,
the computer program product comprising
[0035] a computer readable program code for causing the computer to
generate a three-dimensional reconstruction of the arterial tree
from two or more angiographic images of the arterial tree obtained
from different perspectives;
[0036] b computer readable program code for causing the computer to
determining an orientation of the axis of the artery in the
arterial tree;
[0037] c computer readable program code for causing the computer to
determine from the three-dimensional reconstruction of the arterial
tree at least one perspective of the artery perpendicular to the
axis of the artery; and
[0038] d computer readable program code for causing the computer to
generate a three dimensional reconstruction of the artery from
angiographic images obtained essentially from the determined at
least one perspective.
[0039] In its sixth aspect, the invention provides a program
storage device readable by machine, tangibly embodying a program of
instructions executable by the machine to perform method steps for
diagnosing stenosis in an arterial tree in an individual, said
method steps comprising:
[0040] a generating a three-dimensional reconstruction of the
arterial tree from two or more angiographic images of the arterial
tree obtained from different perspectives;
[0041] b detecting in the three-dimensional reconstruction of the
arterial tree a stenotic artery, the stenotic artery having an
axis;
[0042] c determining an orientation of the axis of the stenotic
artery;
[0043] d determining from the three-dimensional reconstruction of
the arterial tree at least one perspective of the stenotic artery
perpendicular to the axis of the artery;
[0044] e generating a three dimensional reconstruction of the
artery from angiographic images obtained essentially from the
determined at least one perspective; and
[0045] f analyzing the three-dimensional reconstruction of the
artery.
[0046] In its seventh aspect, the invention provides a computer
program product comprising a computer useable medium having
computer readable program code embodied therein for diagnosing
stenosis in an arterial tree in an individual the computer program
product comprising:
[0047] a computer readable program code for causing the computer to
generate a three-dimensional reconstruction of the arterial tree
from two or more angiographic images of the arterial tree obtained
from different perspectives;
[0048] b computer readable program code for causing the computer to
detect in the three-dimensional reconstruction of the arterial tree
a stenotic artery, the stenotic artery having an axis;
[0049] c computer readable program code for causing the computer to
determine an orientation of the axis of the stenotic artery;
[0050] d computer readable program code for causing the computer to
determine from the three-dimensional reconstruction of the arterial
tree at least one perspective of the stenotic artery perpendicular
to the axis of the artery;
[0051] e computer readable program code for causing the computer to
generate a three dimensional reconstruction of the artery from
angiographic images obtained essentially from the determined at
least one perspective;. and
[0052] f computer readable program code for causing the computer to
analyze the three-dimensional reconstruction of the artery.
BRIEF DESCRIPTION OF THE DRAWINGS
[0053] In order to understand the invention and to see how it may
be carried out in practice, a preferred embodiment will now be
described, by way of non-limiting example only, with reference to
the accompanying drawings, in which:
[0054] FIG. 1 shows a cross-sectional view and two projections of a
stenotic artery;
[0055] FIG. 2 is block diagram showing an embodiment of the system
of the invention according to one embodiment of the invention;
and
[0056] FIG. 3 is a flow chart diagram of the process of
constructing a three-dimensional reconstruction of a stenotic
artery.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
[0057] Referring first to FIG. 1, a cross section 100 of a stenotic
artery is shown. The artery has a circular lumen that is partially
occluded by plaque 105. In angiography, the unoccluded portion of
the lumen 110, (indicated in FIG. 1 by cross-hatching) is filled
with a radio-opaque substance. 115a and 115b are two longitudinal
projections of the radio-opacity of the artery as would be obtained
in angiography. The projections 115a and 115b are from orthogonal
perspectives as indicated by the broken lines 120a and 120b. In the
projection 115a the stenosis appears to be non-critical. The
projection 115b, on the other hand, shows maximal narrowing of the
arterial lumen indicating that the stenosis is in fact
critical.
[0058] In FIG. 2, a block diagram of a preferred embodiment of the
system of the invention is shown. An X-ray source 200 and an X-ray
detector 205 are used to obtain angiographic images of an
individual 210. An X-ray beam 212 is produced by the X-ray source
200 and is detected by the detector 205 after having passed through
the body of the individual 210. The analog signal 215 produced by
the detector 205 is converted into a digital signal 225 by
analog-to-digital converter 220. The digital signal 225 is inputted
into a microprocessor 230 and stored in a memory 240. An analog ECG
signal 270 may also be simultaneously obtained from the individual
210. The analog ECG signal 270 is converted into a digital signal
280 by analog-to-digital converter 275 and the digital ECG signal
280 is inputted to the microprocessor 230 and stored in the memory
240. The detector signal 225 and the ECG signal 280 are
synchronized by the microprocessor 230. An operator input 250, that
may be, for example, a key board or a computer mouse, is used to
allow an operator to input instructions to the microprocessor 230.
A display 255 is used to display images either in real-time or
images called up from the memory 240.
[0059] The orientation of the X-ray beam 212 and the plane 260 of
the individual's body may be selected by the operator in order to
produce an image of an arterial tree of the individual, for
example, the coronary artery tree, from a desired perspective. The
operator inputs the desired perspective into the microprocessor 230
by means of operator input 250. The microprocessor 230 then brings
the X-ray source 200 and the detector 205 into the required
orientation by activating a mechanism (not shown) that moves the
X-ray source and the detector into the desired orientation relative
to the individual's body, as is known in the art.
[0060] The microprocessor 230 is programmed to generate a 3D
reconstruction of the arterial tree based upon the obtained images.
The 3D reconstruction of the arterial tree may be represented on
display 255 using pseudo 3D effects such as directional lighting
and shading. In a preferred embodiment, the reconstructed tree is
presented as a stereoscopic pair of images on display 255 to be
viewed by the operator using a stereoscopic viewer. The 3D
reconstruction of the arterial tree may be manipulated on the
display 255 by the operator by means of operator input 250,
allowing him, for example, to zoom in on a specific region or to
rotate the reconstruction on the display to obtain a desired
perspective.
[0061] An artery of interest, for example, a stenotic artery, in an
image or in the 3D reconstructed tree is selected by the operator
or detected by the microprocessor, for example, by gray level
analysis as is known in the art. For example, an image or the
reconstructed tree may be displayed on the display 255, and an
artery selected by the operator by means of input 250. The
microprocessor determines from the 3D reconstruction of the
arterial tree the angular orientation of the selected artery. The
microprocessor then calculates two or more perspectives
perpendicular to the axis of the selected artery. The perspectives
preferably include two orthogonal perspectives. If images of the
selected artery have not already been obtained approximately from
the calculated perspectives, the operator obtains such images. The
microprocessor 230 is programmed to reconstruct a 3D image of the
selected artery based upon these images. The 3D reconstruction of
the artery may be represented on display 255 using pseudo 3D
effects such as directional lighting and shading. In a preferred
embodiment, the reconstruction is presented as a stereoscopic pair
of images on display 255 to be viewed by the operator using a
stereoscopic viewer. The reconstruction of the artery may be
presented to the operator embedded in the 3D reconstruction of the
entire arterial tree.
[0062] The 3D reconstruction of the artery may be manipulated on
the display 255 by the operator by means of operator input 250,
allowing him, for example, to zoom in on a specific region or to
rotate the reconstruction on the display to obtain a desired
perspective, including an optimal perspective or a
cross-section.
[0063] The microprocessor may optionally be programmed to determine
quantitative and qualitative parameters of a stenosis based upon
the 3D reconstruction. Such parameters may include, for example,
the length and severity of a stenosis.
[0064] Referring now to FIG. 3, a flow chart is shown describing a
preferred embodiment of the process of the invention. At step 310
the operator obtains at least two angiographic images of an
arterial tree of the individual 210 from different, preferably
perpendicular, perspectives. The images are displayed on the
display 255 in step 315, and a 3D reconstruction of the arterial
tree is generated from the obtained images 318. The 3D
reconstruction may optionally be displayed on the display 255. The
obtained angiographic images or the 3D reconstructed tree is
examined for arteries of interest, for example, stenotic arteries.
The examination may be performed either automatically by the
microprocessor 230 or by visual examination by the operator (step
320). If no artery of interest is detected in any of the images or
in the 3D reconstructed tree the operator decides whether
additional images are to be obtained from a new perspective (step
330). If at step 330 the operator decides not to obtain additional
images, the process is terminated. If, at step 330 the operator
decides to obtain an additional image, a perspective is selected
and the operator inputs the perspective into the microprocessor
230, and the process then returns to step 315. If in step 320 one
or more arteries of interest are observed, an artery of interest is
selected in step 340. In step 345 the microprocessor calculates two
or more perspectives perpendicular to the axis of the selected
artery (step 348). The perspectives preferably include two
orthogonal perspectives. If images of the selected artery have not
already been obtained approximately from the calculated
perspectives, the operator obtains such images (step 348). In step
350, the microprocessor updates the 3D reconstruction of the
artery. The reconstructed artery is displayed on the display 255 in
step 355 together with parameters describing the artery. For
example, for a stenotic artery, the parameters may include the
severity and length of the stenosis. The reconstructed artery may
be presented to the operator embedded in the 3D reconstruction of
the entire arterial tree. The operator may change the display using
input 250, for example, by rotating the reconstructed artery on the
display 255 so as to change the scale of the reconstruction of the
artery or view the reconstruction from a desired perspective,
including an optimal perspective or a cross-section. The operator
then decides in step 360 whether he wishes to obtain a 3D
reconstruction of another artery of interest in the arterial tree.
If so, the process returns to step 340. If not, additional images
are desired, the process terminates.
[0065] It will also be understood that the system according to the
invention may be a suitably programmed computer. Likewise, the
invention contemplates a computer program being readable by a
computer for executing the method of the invention. The invention
further contemplates a machine-readable memory tangibly embodying a
program of instructions executable by the machine for executing the
method of the invention.
[0066] In the method claims that follow, alphabetic characters used
to designate claim steps are provided for convenience only and do
not imply any particular order of performing the steps.
* * * * *