Determining cardiac wall thickness and motion by imaging and three-dimensional modeling
First Claim
1. A method for analyzing characteristic cardiac parameters of a patient'"'"'s heart, comprising the steps of:
- (a) imaging a heart to produce imaging data;
(b) modeling the heart using the imaging data, producing modeling data corresponding to at least one of an inner surface and an outer surface of the heart, at an end systole and at an end diastole of a cardiac cycle;
(c) defining a center surface that is generally midway between said inner surface and said outer surface, said center surface being defined by a plurality of tiled sections comprising polygons;
(d) projecting the tiled sections onto the inner surface and the outer surface to define volumetric elements having opposite ends on said surfaces, each of the volumetric elements containing a different one of the tiled sections;
(e) determining an area for each of the opposite ends of the volumetric elements;
(f) determining volumes for the volumetric elements;
(g) averaging the areas of the opposite ends of the volumetric elements; and
(h) determining characteristic cardiac parameters for the heart as a function of an average area of the ends and of the volume of the volumetric elements.
4 Assignments
0 Petitions
Accused Products
Abstract
A method for imaging and three-dimensional modeling portions of the heart, particularly, the left ventricular endocardial and epicardial surfaces, using imaging data. Preferably, a transesophageal ultrasound probe is inserted into an esophagus of a patient to provide multiple plane imaging data at end systole and end diastole during a cardiac cycle. The image planes are then traced along the boundaries of the epicardial and endocardial surfaces to produce sets of data points, which are further processed and expanded through interpolation. These data points are used for modeling the endocardial and epicardial surface at the end systole and end diastole extremes of the cardiac cycle. A center surface is constructed between an inner and outer surface of the modeled surfaces of the left ventricle and an average template of tiled sections is mapped onto this center surface. The mapped tiled sections are then projected onto the inner and outer surfaces, defining triangular prisms. By determining the volume of the triangular prisms and an average area for their ends, the range of movement, which is equal to the volume divided by the average area, is determined. Similarly, for changes in wall thickness between the endocardial and epicardial surfaces at end diastole and end systole, the thickening of the cardiac wall is determined.
-
Citations
25 Claims
-
1. A method for analyzing characteristic cardiac parameters of a patient'"'"'s heart, comprising the steps of:
-
(a) imaging a heart to produce imaging data; (b) modeling the heart using the imaging data, producing modeling data corresponding to at least one of an inner surface and an outer surface of the heart, at an end systole and at an end diastole of a cardiac cycle; (c) defining a center surface that is generally midway between said inner surface and said outer surface, said center surface being defined by a plurality of tiled sections comprising polygons; (d) projecting the tiled sections onto the inner surface and the outer surface to define volumetric elements having opposite ends on said surfaces, each of the volumetric elements containing a different one of the tiled sections; (e) determining an area for each of the opposite ends of the volumetric elements; (f) determining volumes for the volumetric elements; (g) averaging the areas of the opposite ends of the volumetric elements; and (h) determining characteristic cardiac parameters for the heart as a function of an average area of the ends and of the volume of the volumetric elements. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A method for analyzing characteristic cardiac parameters of a patient'"'"'s heart, comprising the steps of:
-
(a) imaging at least a portion of a heart to produce a signal that includes first imaging data defining images of an inner surface and an outer surface of the portion of the heart at an end systole and second imaging data defining images of the inner surface and the outer surface of the portion of the heart at the end diastole; (b) producing a first three-dimensional model of the portion of the heart that was imaged using the first and the second imaging data from the signal produced by the imaging, said first three-dimensional model comprising first model data that defines a first modeled inner surface at end systole and a first modeled inner surface at end diastole; (c) producing a second three-dimensional model of the portion of the heart using the first and second imaging data, said second three-dimensional model comprising second model data that represent a second modeled inner surface of the portion of the heart at end diastole and a second modeled outer surface of the portion of the heart at end diastole; (d) defining a first center surface that is disposed substantially midway between the first modeled inner surface and the first modeled outer surfaces, said first center surf;
ace being represented by a plurality of tiled sections;(e) projecting the shape of the tiled sections onto the first modeled inner and outer surfaces to define a plurality of volumetric elements, by extending chords from vertices of the edges to said surfaces, each of said chords being transverse to a plane having an orientation that is an average of orientations for the tiled sections surrounding the chord, the projected shapes on said surfaces respectively corresponding to first and second ends of the volumetric element having sides aligned with the chords that define it, each tiled surface being contained in a different volumetric element; (f) for each volumetric element of interest; (i) determining a mean area of the first and second ends of the volumetric element; (ii) determining a volume for the volumetric element; and (iii) as a function of the mean area of the first and second ends and the volume of the volumetric element, determining a range of motion of the cardiac wall at that volumetric element; (g) defining a second center surface that is disposed substantially midway between the second modeled inner surface and the second modeled outer surfaces, said second center surface being represented by a plurality of tiled sections; (h) projecting the shape of the tiled sections of step (i) onto the second modeled inner and outer surfaces to define a plurality of volumetric elements, by extending chords from vertices of the edges to said surfaces, each of said chords being transverse to a plane having an orientation that is an average of orientations for said tiled sections surrounding the chord, the projected shapes on said surfaces respectively corresponding to first and second ends of the volumetric element having sides aligned with the chords that define it, each tiled surface being contained in a different volumetric element; and (i) for each volumetric element of step (h) of interest; (i) determining a mean area of the first and second ends of said volumetric element; (ii) determining a volume for said volumetric element; and (iii) as a function of the mean area of the first and second ends and the volume of said volumetric element, determining a thickness of the cardiac wall at that volumetric element. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23)
-
-
24. A method for determining at least one characteristic cardiac parameter of a patient'"'"'s heart using imaging data produced by imaging the heart, comprising the steps of:
-
(a) modeling the heart using the imaging data, producing modeling data corresponding to at least one of an inner surface and an outer surface of the heart, at an end systole and at an end diastole of a cardiac cycle; (b) defining a center surface that is generally midway between the inner and the outer surfaces to which the modeling data correspond, said center surface being defined by a plurality of tiled sections comprising polygons; (c) projecting the tiled sections onto the inner and the outer surfaces to define volumetric elements having opposite ends on the two surfaces, each volumetric element containing a different one of the tiled sections; (d) determining an area for the opposite ends of at least one of the volumetric elements; (e) determining a volume for said at least one volumetric element; and (f) determining at least one characteristic cardiac parameter for the heart at said at least one volumetric element, as a function of the area of the opposite ends and of the volume of said at least one volumetric element.
-
-
25. A method for determining at least one characteristic cardiac parameter of a patient'"'"'s heart using modeling data corresponding to at least one of an inner surface and an outer surface of the heart, at an end systole and at an end diastole of a cardiac cycle, comprising the steps of:
-
(a) defining a center surface that is generally midway between the inner and the outer surfaces, said center surface being defined by a plurality of tiled sections comprising polygons; (b) projecting the tiled sections onto the inner and the outer surfaces to define volumetric elements having opposite ends on the inner and the outer surfaces, each of said volumetric elements containing a different one of the tiled sections; (c) determining an area for the opposite ends of at least one of the volumetric elements; (d) determining a volume for said at least one volumetric element; and (e) determining at least one characteristic cardiac parameter for the heart at said at least one volumetric element, as a function of the area of the opposite ends and of the volume of said at least one volumetric element.
-
Specification