Method and system for image processing and patient-specific modeling of blood flow

• US 10,154,883 B2
• Filed: 04/06/2016
• Issued: 12/18/2018
• Est. Priority Date: 08/12/2010
• Status: Active Grant

• Current Assignee: Heartflow Inc.
• Original Assignee: Heartflow Inc.
• Inventors: Taylor, Charles A.
• Primary Examiner(s): GORADIA, SHEFALI DINESH
• Application Number:
  US15/092,393
• Publication Number:
  US 20160246939A1
• Time in Patent Office: 986 Days
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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 for simulating perfusion of the myocardial muscle using computed tomography or computed tomographic angiography, the method comprising:

receiving imaging data of at least a portion of a patient'"'"'s myocardial muscle and one or more coronary blood vessels of the patient'"'"'s heart;

identifying, from the imaging data, different three-dimensional regions of the portion of the patient'"'"'s myocardial muscle, wherein each three-dimensional region is identified based on a location of an outflow boundary of one of the one or more coronary blood vessels or a branch extending from the one or more coronary blood vessels;

generating a three-dimensional model of the portion of the patient'"'"'s myocardial muscle and coronary blood vessels, using the identified three-dimensional regions from the received imaging data;

simulating blood flow through the three-dimensional model and determining, from the simulating, the blood flow into the different three-dimensional regions of the myocardial muscle into which different branches of the coronary blood vessels lead;

simulating local perfusion of the myocardial muscle for the different three-dimensional regions of the myocardial muscle from the determined blood flow into the different three-dimensional regions of the myocardial muscle;

determining one or more three-dimensional regions of the myocardial muscle that are at risk of insufficient perfusion using the simulated local perfusion of the different three-dimensional regions of the myocardial muscle; and

displaying a map of perfusion on the three-dimensional model of the myocardial muscle, based on the simulated local perfusion of the myocardial muscle for the different three-dimensional regions of the myocardial muscle, wherein the map of perfusion displays one or more of the three-dimensional regions, and identifies the one or more three-dimensional regions that are at risk of insufficient perfusion.

2. The method of claim 1, wherein the simulating of the blood flow includes:

segmenting the patient'"'"'s coronary blood vessels based on the received imaging data;

calculating a model of the coronary blood vessels on the basis of the segmented coronary blood vessels; and

simulating the blood flow with the aid of the model.

3. The method of claim 1, wherein the simulating of the blood flow is done using a lattice Boltzmann method.

4. The method of claim 1, further comprising simulating the blood flow using a statistical model to determine time functions for an arterial inflow and a venous outflow from the imaging data on the basis of an accumulation of contrast agent in the coronary blood vessels.

5. The method of claim 4, further comprising simulating the blood flow using data of an injection protocol used for administering the contrast agent for the purpose of determining the time functions.

6. The method of claim 1, wherein the simulating of the local perfusion of the myocardial muscle includes:

simulating a dynamic accumulation of contrast agent in different branches of the coronary blood vessels to determine anatomical characteristics of the different branches of the coronary blood vessels affecting local perfusion; and

calculating perfusion parameters for the perfusion of the myocardial muscle from the anatomical characteristics affecting local perfusion.

7. A non-transitory computer readable medium storing computer program instructions, which when operated on a processor, cause the processor to perform operations comprising:

receiving imaging data of at least a portion of a patient'"'"'s myocardial muscle and one or more coronary blood vessels of the patient'"'"'s heart;

identifying, from the imaging data, different three-dimensional regions of the portion of the patient'"'"'s myocardial muscle, wherein each three-dimensional region is identified based on a location of an outflow boundary of one of the one or more coronary blood vessels or a branch extending from the one or more coronary blood vessels;

generating a three-dimensional model of the portion of the patient'"'"'s myocardial muscle and coronary blood vessels, using the identified three-dimensional regions from the received imaging data;

simulating blood flow through the three-dimensional model and determining, from the simulating, the blood flow into the different three-dimensional regions of the myocardial muscle into which different branches of the coronary blood vessels lead;

simulating local perfusion of the myocardial muscle for the different three-dimensional regions of the myocardial muscle from the determined blood flow into the different three-dimensional regions of the myocardial muscle;

determining one or more three-dimensional regions of the myocardial muscle that are at risk of insufficient perfusion using the simulated local perfusion of the different three-dimensional regions of the myocardial muscle; and

displaying a map of perfusion on the three-dimensional model of the myocardial muscle, based on the simulated local perfusion of the myocardial muscle for the different three-dimensional regions of the myocardial muscle, wherein the map of perfusion displays one or more of the three-dimensional regions, and identifies the one or more three-dimensional regions that are at risk of insufficient perfusion.

8. The non-transitory computer readable medium of claim 7, wherein the simulating of the blood flow includes:

segmenting the patient'"'"'s coronary blood vessels based on the received imaging data;

calculating a model of the coronary blood vessels on the basis of the segmented coronary blood vessels; and

simulating the blood flow with the aid of the model.

9. The non-transitory computer readable medium of claim 7, wherein the simulating of the blood flow is done using a lattice Boltzmann method.

10. The non-transitory computer readable medium of claim 7, further comprising simulating the blood flow using a statistical model to determine time functions for an arterial inflow and a venous outflow from the imaging data on the basis of an accumulation of contrast agent in the coronary blood vessels.

11. The non-transitory computer readable medium of claim 10, further comprising simulating the blood flow using data of an injection protocol used for administering the contrast agent for the purpose of determining the time functions.

12. The non-transitory computer readable medium of claim 7, wherein the simulating of the local perfusion of the myocardial muscle includes:

simulating a dynamic accumulation of contrast agent in different branches of the coronary blood vessels to determine anatomical characteristics of the different branches of the coronary blood vessels affecting local perfusion; and

calculating perfusion parameters for the perfusion of the myocardial muscle from the anatomical characteristics affecting local perfusion.

13. A system for simulating perfusion of the myocardial muscle with the aid of non-dynamic computed tomography or computed tomographic angiography, comprising:

a data storage device storing instructions for simulating perfusion of the myocardial muscle with the aid of non-dynamic computed tomographic angiography; and

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

receiving imaging data of at least a portion of a patient'"'"'s myocardial muscle and one or more coronary blood vessels of the patient'"'"'s heart;

identifying, from the imaging data, different three-dimensional regions of the portion of the patient'"'"'s myocardial muscle, wherein each three-dimensional region is identified based on a location of an outflow boundary of one of the one or more coronary blood vessels or a branch extending from the one or more coronary blood vessels;

generating a three-dimensional model of the portion of the patient'"'"'s myocardial muscle and coronary blood vessels, using the identified three-dimensional regions from the received imaging data;

simulating blood flow through the three-dimensional model and determining, from the simulating, the blood flow into the different three-dimensional regions of the myocardial muscle into which different branches of the coronary blood vessels lead;

simulating local perfusion of the myocardial muscle for the different three-dimensional regions of the myocardial muscle from the determined blood flow into the different three-dimensional regions of the myocardial muscle;

determining one or more three-dimensional regions of the myocardial muscle that are at risk of insufficient perfusion using the simulated local perfusion of the different three-dimensional regions of the myocardial muscle; and

displaying a map of perfusion on the three-dimensional model of the myocardial muscle, based on the simulated local perfusion of the myocardial muscle for the different three-dimensional regions of the myocardial muscle, wherein the map of perfusion displays one or more of the identified three-dimensional regions, and identifies the one or more three-dimensional regions that are at risk of insufficient perfusion.

14. A computed tomography scanner comprising the system as claimed in claim 13.

15. The system of claim 13, further configured for:

segmenting the patient'"'"'s coronary blood vessels based on the received imaging data;

calculating a model of the coronary blood vessels on the basis of the segmented

coronary blood vessels; and

simulating the blood flow with the aid of the model.

16. The system of claim 13, further configured for:

simulating the blood flow using a lattice Boltzmann method.

17. The system of claim 13, further configured for:

using a statistical model to determine time functions for an arterial inflow and a

venous outflow from the imaging data on the basis of an accumulation of contrast agent in the coronary blood vessels.

18. The system of claim 17, further configured for:

using data of an injection protocol used for administering the contrast agent for the purpose of determining the time functions.

19. The system of claim 13, further configured for:

simulating a dynamic accumulation of contrast agent in the different branches of the coronary blood vessels to determine anatomical characteristics of the different branches of the coronary blood vessels affecting local perfusion;

calculating perfusion parameters for the perfusion of the myocardial muscle from the anatomical characteristics affecting local perfusion.