Method and system for image processing to determine patient-specific blood flow characteristics

• US 9,706,925 B2
• Filed: 12/30/2015
• Issued: 07/18/2017
• Est. Priority Date: 08/12/2010
• Status: Active Grant

• Current Assignee: Heartflow Inc.
• Original Assignee: Heartflow Inc.
• Inventors: Taylor, Charles A.
• Primary Examiner(s): HEIDEMANN, JASON E
• Application Number:
  US14/985,200
• Publication Number:
  US 20160110867A1
• Time in Patent Office: 566 Days
• Field of Search: None
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Abstract

Embodiments include a system for determining cardiovascular information for a patient. The system may include at least one computer system configured to receive patient-specific data regarding a geometry of the patient'"'"'s heart, and create a three-dimensional model representing at least a portion of the patient'"'"'s heart based on the patient-specific data. The at least one computer system may be further configured to create a physics-based model relating to a blood flow characteristic of the patient'"'"'s heart and determine a fractional flow reserve within the patient'"'"'s heart based on the three-dimensional model and the physics-based model.

Claims

1. A method of image analysis to produce a cardiovascular index, the method comprising:

receiving vascular image data including;

relative positions in one or more two-dimensional angiographic images of a plurality of vascular segments linked by branch points, and at least one lesion for which a respective lesion metric includes one or more of a cross-sectional area of a stenotic segment, a plaque strength, a plaque stress, and a size and/or position relative to the vascular segments;

determining automatically a plurality of lesion-related vascular metrics for each of a plurality of said vascular segments, based on at least one angiographic image of said received image data;

determining at least one subscore based on a function of said plurality of lesion-related vascular metrics, and on said position of the lesion within the vascular segments and relative to the branch points;

determining a myocardial perfusion risk index based on said at least one subscore; and

outputting said myocardial perfusion risk index to an electronic storage medium or display.

2. The method of claim 1, wherein said lesion-related vascular metrics further include a measurement of a reduction of a vascular cross-sectional area for one or more vascular segments of the plurality of vascular segments.

3. The method of claim 1, wherein said vascular metrics comprise a metric which is a function of vascular segment position.

4. The method of claim 1, wherein said vascular image data images the arterial vasculature of the heart.

5. The method of claim 1, wherein the at least one subscore is determined based on a ratio of one or more metrics of plaque stress to one or more metrics of plaque strength.

6. The method of claim 1, wherein said determining of said vascular metrics comprises mapping image data measurement values to positions within said plurality of vascular segments.

7. The method of claim 6, wherein said positions are examinable to determine position along said plurality of vascular segments.

8. The method of claim 7, wherein said vascular metrics comprise measurements of vascular segment stenosis.

9. The method of claim 6, wherein said positions are associated with anatomically identifying vascular segment labels.

10. The method of claim 1, wherein said determining of vascular metrics comprises determining a vascular model representation for said plurality of vascular segments based on said received vascular image data.

11. The method of claim 10, wherein said determining of vascular metrics comprises

modifying the vascular model representation to remove one or more stenoses based on said received image data.

12. The method of claim 1, comprising:

determining to perform treatment in an imaged patient based on said received output, wherein at the time of said determination, the patient remains catheterized from the imaging procedure producing said received vascular image data.

13. A method of image analysis to produce a cardiovascular index, the method comprising:

receiving vascular image data including;

relative positions in one or more two-dimensional angiographic images of a plurality of vascular segments linked by branch points, and at least one lesion for which a respective lesion metric includes one or more of a cross-sectional area of a stenotic segment, a plaque strength, a plaque stress, and a size and/or position relative to the vascular segments;

determining automatically a plurality of lesion-related vascular metrics for each of a plurality of said vascular segments, based on at least one angiographic image of said received image data;

determining at least one subscore based on a function of said plurality of lesion-related vascular metrics, and on said position of the lesion within the vascular segments and relative to the branch points wherein, the at least one subscore is determined based upon a plaque rupture vulnerability index, a hemodynamic model, and/or the sizes of plaques and arterial vasculature;

determining a myocardial perfusion risk index based on said at least one subscore; and

outputting said myocardial perfusion risk index to an electronic storage medium or display.

14. A system for image analysis to automatically determine a myocardial perfusion risk index, comprising:

a data storage device storing instructions for image analysis to automatically determine a myocardial perfusion risk index; and

a processor configured to execute the instructions to perform a method including;

receiving vascular image data including;

relative positions in one or more two-dimensional angiographic images of a plurality of vascular segments linked by branch points, and at least one lesion for which a respective lesion metric includes one or more of a cross-sectional area of a stenotic segment, a plaque strength, a plaque stress, and a size and/or position relative to the vascular segments;

determining automatically a plurality of lesion-related vascular metrics for each of a plurality of said vascular segments, based on at least one angiographic image of said received image data;

determining at least one subscore based on a function of said plurality of lesion-related vascular metrics, and on said position of the lesion within the vascular segments and relative to the branch points;

determining a myocardial perfusion risk index based on said at least one subscore; and

outputting said myocardial perfusion risk index to an electronic storage medium or display.

15. The system of claim 14, wherein the method further comprises:

reconstructing a data structure representing a connected group of vascular segments from the received vascular image data.

16. The system of claim 15, wherein said data structure represents branch connection relationships among said connected group of vascular segments.