System and method for local deformable motion analysis

• US 7,421,101 B2
• Filed: 10/01/2004
• Issued: 09/02/2008
• Est. Priority Date: 10/02/2003
• Status: Active Grant

• Current Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Original Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Inventors: Krishnan, Sriram, Georgescu, Bogdan, Zhou, Xiang Sean, Comaniciu, Dorin
• Primary Examiner(s): Bella; Matthew C.
• Assistant Examiner(s): Lee; John W
• Application Number:
  US10/957,380
• Publication Number:
  US 20050074154A1
• Time in Patent Office: 1,432 Days
• Field of Search: 382/107, 382/103, 382/168, 382/128
• US Class Current: 382/128
• CPC Class Codes: G06T 2207/10132 Ultrasound image
• CPC Class Codes: G06T 2207/30048 Heart; Cardiac
• CPC Class Codes: G06T 7/0016 involving temporal comparison
• CPC Class Codes: G06T 7/20 Analysis of motion motion estimation for coding, decoding, compressing or decompressing digital video signals H04N19/43, H04N19/51
• CPC Class Codes: G06T 7/251 involving models

Abstract

A system and method for local deformable motion analysis accurately tracks the motion of an object such that local motion of an object is isolated from global motion of an object. The object is viewed in an image sequence and image regions are sampled to identify object image regions and background image regions. The motion of at least one of the identified background image regions is estimated to identify those background image regions affected by global motion. Motion from multiple background image regions are combined to measure the global motion in that image frame. The measured global motion in the object image regions are compensated to measure local motion of the object and the local motion of the object is tracked.

Claims

1. A method for tracking local deformable cardiac motion of a myocardial wall of a left ventricle (LV), the left ventricle being viewed in an image sequence, the method comprises the steps of:

sampling points on a LV contour in consecutive image frames to identify LV image regions and background image regions;

estimating motion of at least one of the identified background image regions to identify those background image regions affected by global motion;

measuring the global motion in the identified background regions by measuring rotation and translation of the identified background regions;

combining motion from multiple background image regions to measure the global motion in the consecutive image frames;

compensating for the measured global motion in the LV image regions to measure local deformable motion of the myocardial wall of the LV by calculating a period of cardiac motion for the left ventricle, the period being calculated by measuring the area of the left ventricle in each frame using control points identified on the left ventricle wall and identifying changes in the size of the left ventricle over the period;

matching the LV image regions in the consecutive image frames to obtain global translation and rotation of the LV image region; and

independently tracking each control point in the image sequence to determine the local deformable motion of the LV.

2. The method of claim 1 wherein said estimating motion step is performed using an optical flow estimation technique.

3. The method of claim 2 wherein said estimating motion step is performed using an information fusion technique.

4. The method of claim 1 wherein least square matching is used to measure rotation and translation of a background image region.

5. The method of claim 1 wherein the step of calculating a period of cardiac motion further comprises the steps of:

identifying points on a wall of the left ventricle;

measuring the change in size of the left ventricle over time by tracking movement of the identified points; and

using autocorrelation analysis of the measured points to identify the period.

6. The method of claim 1 wherein the image is an ultrasound image.

7. The method of claim 1 wherein the image is a 3D volume of the LV.

8. A system for tracking local deformable cardiac motion of a myocardial wall of a left ventricle (LV), the left ventricle being viewed in an image sequence, the system comprising:

means for sampling points on a LV contour in consecutive frames to identify LV image regions and background image regions;

means for estimating motion of at least one of the identified background image regions to identify those background image regions affected by global motion;

means for measuring the global motion in the identified background regions by measuring rotation and translation of the identified background regions;

means for combining motion from multiple background image regions to measure the global motion in the consecutive image frames;

means for compensating for the measured global motion in the LV image regions to measure local motion of the myocardial wall of the LV by calculating a period of cardiac motion for the left ventricle, the period being calculated by measuring the area of the left ventricle in each frame using control points identified on the left ventricle wall and identifying changes in the size of the left ventricle over the period;

matching the LV image regions in the consecutive image frames to obtain global translation and rotation of the LV image region; and

means for independently tracking each control point in the image sequence to determine the local motion of the LV.

9. The system of claim 8 wherein said motion is estimated using an optical flow estimation technique.

10. The system of claim 9 wherein said motion is estimated using an information fusion technique.

11. The system of claim 8 wherein least square matching is used to measure rotation and translation of a background image region.

12. The system of claim 8 wherein said means for calculating a period of cardiac motion further comprises:

identifiying points on a wall of the left ventricle;

measuring the change in size of the left ventricle over time by tracking movement of the identified points; and

using autocorrelation analysis of the measured points to identify the period.

13. The system of claim 8 wherein the image is an ultrasound image.

14. The system of claim 8 wherein the image is a 3D volume of the LV.