METHOD AND APPARATUS FOR AUTOMATICALLY ADJUSTING USER INPUT LEFT VENTRICLE POINTS

• US 20100010347A1
• Filed: 07/11/2008
• Published: 01/14/2010
• Est. Priority Date: 07/11/2008
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Smirin, Nahum, Friedman, Zvi M., Lysyansky, Peter
• Granted Patent: US 8,319,770 B2
• Time in Patent Office: Days
• US Class Current: 600/443
• CPC Class Codes: A61B 6/503 for diagnosis of the heart
• CPC Class Codes: A61B 8/08 Detecting organic movements or changes, e.g. tumours, cysts, swellings A61B8/02 - A61B8/06 take precedence
• CPC Class Codes: A61B 8/0883 for diagnosis of the heart
• CPC Class Codes: A61B 8/469 for selection of a region of interest
• CPC Class Codes: G06T 2207/10132 Ultrasound image
• CPC Class Codes: G06T 2207/20101 Interactive definition of point of interest, landmark or seed
• CPC Class Codes: G06T 2207/30048 Heart; Cardiac
• CPC Class Codes: G06T 7/70 Determining position or orientation of objects or cameras camera calibration G06T7/80

Abstract

A method and system for optimizing user input points that identify points within an image of a left ventricle of a heart includes identifying user input points on an image. The user input points include an apical point and left and right basal points positioned proximate to an endocardium of a left ventricle. An adjusted apical point is determined based on at least an autocorrelation of points in the image proximate to the apical point. The adjusted apical point is displayed on the image.

Claims

1. A method for optimizing user input points that identify points within an image of a left ventricle of a heart, the method comprising:

identifying user input points on an image, wherein the user input points comprise an apical point, a left basal point and a right basal point positioned proximate to an endocardium of a left ventricle;

determining an adjusted apical point based on at least an autocorrelation of points in the image proximate to the apical point; and

displaying the adjusted apical point on the image.

2. The method of claim 1, wherein the points in the image are defined along a line extending between the apical point and an edge of the image proximate to the apical point, the line being configured to intersect a middle point between the left and right basal points, wherein the determining the adjusted apical point further comprises:

temporally averaging values associated with the points over a period of time;

autocorrelating the temporally averaged values; and

determining an intersection point on the line based on a change in autocorrelation values determined for consecutive points along the line, the adjusted apical point being further determined based on the intersection point.

3. The method of claim 1, wherein the determining the adjusted apical point further comprises:

determining an intersection point based on a change in autocorrelation values determined for consecutive points along a line extending between the apical point and an edge of the image proximate to the apical point, the line being configured to intersect a middle point between the left and right basal points; and

identifying a width between the endocardium and an epicardium of the left ventricle based on the apical point and the left and right basal points, the adjusted apical point being further determined based on the intersection point and the width.

4. The method of claim 1, further comprising adjusting at least one of the left basal point and the right basal point based on a left leaflet and a right leaflet, respectively, of a mitral valve, wherein the left leaflet is located proximate to the left basal point and the right leaflet is located proximate to the right basal point.

5. The method of claim 1, further comprising:

determining a left leaflet shape of a left leaflet of a mitral valve, the left leaflet being located proximate to the left basal point;

extending border lines from the adjusted apical point through each of a plurality of points located proximate to the left basal point, the plurality of points having a center of gravity point corresponding to the left basal point, the border lines intersecting the left leaflet shape at intersection points, the plurality of points being adjusted based on the intersection points, the center of gravity point being adjusted based on the adjusted plurality of points; and

adjusting the left basal point based on the adjusted center of gravity point.

6. The method of claim 1, wherein the image comprises one of a two chamber view and a four chamber view, the method further comprising:

determining a right leaflet shape based on a best fit equation, the right leaflet shape forming a shape of a right leaflet of a mitral valve, the right leaflet being located proximate to the right basal point;

extending border lines from the adjusted apical point through each of a plurality of points located proximate to the right basal point, the plurality of points having a center of gravity point corresponding to the right basal point, the border lines intersecting the right leaflet shape at intersection points, the plurality of points being adjusted based on the intersection points, the center of gravity point being adjusted based on the adjusted plurality of points; and

adjusting the right basal point based on the adjusted center of gravity point.

7. The method of claim 1, further comprising:

adjusting a plurality of points based on intersection points between a left leaflet shape based on a best fit equation and border lines extending from the adjusted apical point, each of the border lines extending through a point within the plurality of points, the left leaflet shape forming a shape of a left leaflet of the mitral valve, the plurality of points located proximate to the left basal point and having a center of gravity point corresponding to the left basal point;

determining a first average distance between the plurality of points and the center of gravity point and a second average distance between an adjusted plurality of points and an adjusted center of gravity point, respectively, the adjusted center of gravity point being based on the adjusted plurality of points; and

positioning the left basal point at the adjusted center of gravity point when the second average distance is less than the first average distance.

8. The method of claim 1, wherein the image comprises an apical long axis (APLAX) view, the method further comprising:

defining a plurality of points located proximate to the right basal point, the plurality of points having a center of gravity point located at the right basal point; and

adjusting the plurality of points based on a first point located between the left basal point and the adjusted apical point and a second point located between the left basal point and the right basal point, the right basal point being adjusted based on an adjusted center of gravity point associated with the adjusted plurality of points.

9. The method of claim 1, further comprising automatically defining on the image at least one of the endocardium and an epicardium of the left ventricle based on the adjusted apical point and the left and right basal points.

10. An ultrasound system comprising:

a display configured to display ultrasound images, the ultrasound images comprising at least one of a two chamber view, a four chamber view and an apical long axis (APLAX) view;

a user interface configured to receive a user input, the input defining an apical point, a left basal point and a right basal point proximate to an endocardium of a left ventricle on an ultrasound image; and

a processor module configured to automatically adjust at least one of the left and right basal points based on at least the apical point, the display further configured to display the apical point and the adjusted left and right basal points on the ultrasound image.

11. The system of claim 10, wherein the processor module is further configured to indicate the endocardium on the display with a smoothed line that extends from the apical point to one of the left basal point and the adjusted left basal point and to indicate the endocardium on the display with another smoothed line that extends from the apical point to one of the right basal point and the adjusted right basal point.

12. The system of claim 10, wherein the processor module is further configured to determine an intersection point based on a difference between autocorrelation values determined for consecutive points along a line extending between the apical point and an edge of the image proximate to the apical point, the processor module further configured to adjust the apical point based on the intersection point.

13. The system of claim 10, the processor module further configured to identify a width between the endocardium and an epicardium of the left ventricle and to adjust the apical point based on the width.

14. The system of claim 10, wherein the ultrasound image is the APLAX view, wherein the processor module is further configured to define a plurality of points located proximate to the right basal point, the plurality of points having a center of gravity point located at the right basal point, the processor module further configured to determine a first point located approximately one-third of a distance from one of the left basal point and the adjusted left basal point to the apical point and to determine a second point located approximately half-way between each of the plurality of points and one of the left basal point and the adjusted left basal point, the processor module further configured to adjust the right basal point based on shortest distances from the first and second points to border lines extending from the apical point to each of the plurality of points.

15. A computer readable medium for optimizing user input points that identify points within an image of a left ventricle of a heart, comprising:

instructions configured to identify user input points on an image, wherein the user input points comprise an apical point, a left basal point and a right basal point defined proximate to an endocardium of the left ventricle;

instructions configured to adjust at least one of the apical point and the left and right basal points based on a spatial relationship of the point to at least one of the other points; and

instructions configured to display on the image at least one of the apical point and an adjusted apical point, at least one of the left basal point and an adjusted left basal point, and at least one of the right basal point and an adjusted right basal point.

16. The computer readable medium of claim 15, further comprising:

instructions configured to determine an intersection point based on a biggest difference between autocorrelation values of consecutive points in the image, the points located between the apical point and an edge of the image away from the left and right basal points, the autocorrelation values being temporally averaged over a heart cycle;

instructions configured to determine a width between the endocardium and an epicardium of the left ventricle; and

instructions configured to adjust the apical point based on the intersection point and the width.

17. The computer readable medium of claim 15, further comprising:

instructions configured to iteratively adjust a plurality of points based on intersection points between a left leaflet shape based on a best fit equation and border lines extending from one of the adjusted apical point and the apical point, each of the border lines passing through one point of the plurality of points, the left leaflet shape forming a shape of a left leaflet of a mitral valve, the plurality of points located proximate to the left basal point and having a center of gravity point corresponding to the left basal point;

instructions configured to determine an average distance between the plurality of points and the center of gravity point and to determine average distances between iteratively adjusted pluralities of points and iteratively adjusted centers of gravity, the iteratively adjusted centers of gravity points being based on corresponding ones of the iteratively adjusted pluralities of points; and

instructions configured to adjust the left basal point to a position of an adjusted center of gravity point when a difference between successive average distances is less than a predetermined limit.

18. The computer readable medium of claim 15, further comprising:

instructions configured to define a plurality of points located proximate to the right basal point, the plurality of points having a center of gravity point located at the right basal point;

instructions configured to determine a first point located approximately one-third of a distance from one of the adjusted left basal point and the left basal point to the adjusted apical point and to determine second points located approximately half-way between each of the plurality of points and one of the adjusted left basal point and the left basal point; and

instructions configured to adjust the right basal point based on shortest distances from the first and second points to border lines extending from one of the adjusted apical point and the apical point to each of the plurality of points.

19. The computer readable medium of claim 15, further comprising:

instructions configured to determine a right leaflet shape of a right leaflet of a mitral valve based on a best fit equation; and

instructions configured to further adjust the right basal point based on the right leaflet shape.

20. The computer readable medium of claim 15, further comprising:

instructions configured to determine a left leaflet shape of a left leaflet of a mitral valve based on a best fit equation; and

instructions configured to further adjust the left basal point based on the left leaflet shape.