Method for aiding stent-assisted coiling of intracranial aneurysms by virtual parent artery reconstruction

• US 20060184066A1
• Filed: 02/15/2005
• Published: 08/17/2006
• Est. Priority Date: 02/15/2005
• Status: Abandoned Application

• Current Assignee: Baylor College of Medicine (Baylor College)
• Original Assignee: Baylor College of Medicine (Baylor College)
• Inventors: Karmonik, Christof, Mawad, Michel E.
• Application Number:
  US11/058,131
• Publication Number:
  US 20060184066A1
• Time in Patent Office: Days
• US Class Current: 600/587
• CPC Class Codes: A61B 17/12022 Occluding by internal devices, e.g. balloons or releasable wires plugging an opening in the wall of an organ A61B17/0057; occluders for the cervical canal A61F6/146; vas deferens occluders A61F6/20
• CPC Class Codes: A61B 2017/00712 simulating mathematical properties, e.g. for testing of positioning in the isocentre or focus
• CPC Class Codes: A61B 2017/00725 Calibration or performance testing
• CPC Class Codes: A61B 5/103 Detecting, measuring or recording devices for testing the shape, pattern, colour, size or movement of the body or parts thereof, for diagnostic purposes A61B5/08 takes precedence; measuring aids for tailors A41H1/00; measuring instruments specially adapted for dentistry A61C19/04

Abstract

A method of creating a surface model of an intracranial aneurysm in an artery having a lumen, the aneurysm having a neck and a dome and the virtual reconstruction of the parent artery across the lateral extension of the aneurysm neck. The method includes the steps of: determining a center and radius of the artery over the lateral extension of the aneurysm; determining the boundary points that mark the boundary between the aneurysm neck and the artery; determining the angle of the aneurysm neck with respect to the artery, for various cross sections of the neck; determining the length of the neck; determining the height of the dome; estimating the area of the neck; and creating the surface model of the intracranial aneurysm in the artery, using the results from the previous steps.

Claims

1. A method of creating a surface model of an intracranial aneurysm in an artery having a lumen, the aneurysm having a neck and a dome, the method comprising the steps of:

a. determining a center and radius of the artery over the lateral extension of the aneurysm;

b. determining the boundary points that mark the boundary between the aneurysm neck and the artery;

c. determining the angle of the aneurysm neck with respect to the artery, for various cross sections of the neck;

d. determining the length of the neck;

e. determining the height of the dome;

f. estimating the area of the neck; and

g. creating the surface model of the intracranial aneurysm in the artery, using the results from the previous steps.

2. The method of claim 1, wherein the step of determining a center and radius of the artery comprises the steps of:

a. constructing a 3D maximum intensity projection to visualize the orientation of the parent artery and the aneurysm; and

b. creating a set of 2D cross sections oriented approximately perpendicular to the axis of the artery.

c. sorting the 2D cross sections to discard the neck cross sections; and

d. iteratively determining the center and radius of the artery for all remaining cross sections over the lateral extension of the aneurysm.

3. The method of claim 2, wherein the step of determining the angle of the aneurysm neck comprises the steps of:

a. identifying the first and the last aneurysm boundary points; and

b. determining the angle of the aneurysm neck by taking the difference between the angles of the first and the last aneurysm boundary points.

4. The method of claim 3, wherein the step of determining the area of the aneurysm neck comprises the steps of:

a. summing all the neck angles to create a sum; and

b. multiplying the sum by the average artery radius and by the thickness of the 2D cross sections.

5. A computer system configured in any manner for performing a method of creating a surface model of an intracranial aneurysm in an artery having a lumen, the aneurysm having a neck and a dome, the computer system comprising:

a. means for determining a center and radius of the artery over the lateral extension of the aneurysm;

b. means for determining the boundary points that mark the boundary between the aneurysm neck and the artery;

c. means for determining the angle of the aneurysm neck with respect to the artery, for various cross sections of the neck;

d. means for determining the length of the neck;

e. means for determining the height of the dome;

f. means for estimating the area of the neck; and

g. means for creating the surface model of the intracranial aneurysm in the artery, using the results from the previous steps.

6. A computer-readable storage medium encoded with executable instructions, representing a computer program, to cause a computer to perform a method of creating a surface model of an intracranial aneurysm in an artery having a lumen, the aneurysm having a neck and a dome, the method comprising the steps of:

a. determining a center and radius of the artery over the lateral extension of the aneurysm;

b. determining the boundary points that mark the boundary between the aneurysm neck and the artery;

c. determining the angle of the aneurysm neck with respect to the artery, for various cross sections of the neck;

d. determining the length of the neck;

e. determining the height of the dome;

f. estimating the area of the neck; and

g. creating the surface model of the intracranial aneurysm in the artery, using the results from the previous steps.

7. A method of allowing visualization of a virtual stent deployed across an aneurysm ostium, the method comprising the steps of:

a. manually clipping a 3D-DSA data to obtain a volume of interest containing the aneurysm and proximal and distal segments of a healthy parent artery;

b. computing the centerline of the normal segments of the parent artery, proximal and distal to the aneurysm;

c. from these centerline segments, interpolating the centerline of the parent artery across the aneurysm ostium;

d. obtaining a set of contiguous 2D cross sections containing the entire volume of the normal parent artery segments and the aneurysm, and oriented perpendicular to the interpolated centerline;

e. for each cross section containing a portion of the aneurysm, linearly interpolating the corresponding radius of the virtual parent artery; and

f. projecting the resulting reconstruction for analysis.

8. The method of claim 7, wherein the step of computing the centerline of the normal segments uses image post-processing skeletonization algorithms.

9. The method of claim 8, wherein the step of linearly interpolating the corresponding radius of the virtual parent artery uses the radii measured at the normal proximal and distal segments of the parent artery.

10. The method of claim 9, wherein the step of projecting the resulting reconstruction for analysis is done in three different views:

a. as a series of 2D cross sections;

b. as a 3D cut surface reconstruction; and

c. as a 3D surface rendered volume.

11. The method of claim 10, wherein the projection as a 3D cut surface reconstruction is clipped by a cut plane so as to allow inspection of the inside of the aneurysm.

12. A computer system configured in any manner for performing a method of allowing visualization of a virtual stent deployed across an aneurysm ostium, the computer system comprising:

a. means for manually clipping a 3D-DSA data to obtain a volume of interest containing the aneurysm and proximal and distal segments of a healthy parent artery;

b. means for computing the centerline of the normal segments of the parent artery, proximal and distal to the aneurysm, using image post-processing skeletonization algorithms;

c. means for from these centerline segments, interpolating the centerline of the parent artery across the aneurysm ostium;

d. means for obtaining a set of contiguous 2D cross sections containing the entire volume of the normal parent artery segments and the aneurysm, and oriented perpendicular to the interpolated centerline;

e. means for linearly interpolating the corresponding radius of the virtual parent artery for each cross section containing a portion of the aneurysm and;

f. means for projecting the resulting reconstruction for analysis.

13. A computer-readable storage medium encoded with executable instructions, representing a computer program, to cause a computer to perform a method of allowing visualization of a virtual stent deployed across an aneurysm ostium, the method comprising the steps of:

a. manually clipping a 3D-DSA data to obtain a volume of interest containing the aneurysm and proximal and distal segments of a healthy parent artery;

b. computing the centerline of the normal segments of the parent artery, proximal and distal to the aneurysm;

c. from these centerline segments, interpolating the centerline of the parent artery across the aneurysm ostium;

d. obtaining a set of contiguous 2D cross sections containing the entire volume of the normal parent artery segments and the aneurysm, and oriented perpendicular to the interpolated centerline;

e. for each cross section containing a portion of the aneurysm, linearly interpolating the corresponding radius of the virtual parent artery; and

h. projecting the resulting reconstruction for analysis.