Method and system for patient-specific modeling of blood flow

• US 8,315,814 B2
• Filed: 01/27/2011
• Issued: 11/20/2012
• Est. Priority Date: 08/12/2010
• Status: Active Grant

• Current Assignee: Heartflow Inc.
• Original Assignee: Heartflow Inc.
• Inventors: Taylor, Charles A., Fonte, Timothy A., Zarins, Christopher K.
• Primary Examiner(s): Clow, Lori A
• Application Number:
  US13/014,857
• Publication Number:
  US 20120041324A1
• Time in Patent Office: 663 Days
• Field of Search: None
• US Class Current: 702/19
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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 system for determining neurovascular information for a patient, the system comprising:

at least one computer system configured to;

receive patient-specific data regarding a geometry of an anatomical structure of the patient, the anatomical structure including at least a portion of a plurality of cerebral arteries and at least a portion of brain tissue connected to the cerebral arteries;

create a three-dimensional model representing the anatomical structure based on the patient-specific data;

divide at least a portion of the three-dimensional model representing the brain tissue into segments; and

determine perfusion information associated with at least one of the brain tissue segments based on the three-dimensional model and a physics-based model relating to the anatomical structure.

2. The system of claim 1, wherein the at least one computer system is further configured to determine the perfusion information by determining at least one of blood flow, blood pressure, or blood velocity at a plurality of locations within the at least one brain tissue segment.

3. The system of claim 1, wherein the patient-specific data includes imaging data.

4. The system of claim 3, wherein the imaging data is provided by computed tomography or magnetic resonance imaging techniques.

5. The system of claim 3, wherein the at least one computer system is configured to create the three-dimensional model based on the imaging data by locating boundaries of lumens of the plurality of cerebral arteries using the imaging data.

6. The system of claim 5, wherein the at least one computer system is configured to locate the boundaries based on changes in intensity values in the imaging data.

7. The system of claim 1, wherein the cerebral arteries include at least one of an extracranial artery or an intracranial artery.

8. The system of claim 1, wherein the physics-based model includes at least one lumped parameter model representing blood flow through boundaries of the three-dimensional model.

9. The system of claim 1, wherein the at least one computer system is configured to simulate at least one physiological condition of the patient and determine the information regarding the blood flow characteristic based on the at least one physiological condition, the at least one physiological condition including at least one of a level of exercise, exertion, stress, hypertension, hypotension, medication, or baroreceptor response, a posture, or an autonomic feedback control.

10. The system of claim 9, wherein:

the at least one physiological condition includes at least one of the level of exercise, exertion, stress, hypertension, or hypotension, and

at least one parameter of the physics-based model depends on the at least one physiological condition, the at least one parameter including at least one of a cerebral artery resistance of the patient, an aortic blood pressure of the patient, or a heart rate of the patient.

11. The system of claim 1, wherein the patient-specific data includes computed tomography imaging data.

12. The system of claim 1, wherein the at least one computer is further configured to determine the perfusion information by:

determining information relating to an amount of flow from an outlet boundary associated with at least one of the cerebral arteries, the at least one cerebral artery being connected to the at least one brain tissue segment, and

determining information relating to a volume of the at least one brain tissue segment.

13. The system of claim 12, wherein the at least one computer is further configured to determine the perfusion information by dividing the determined information relating to the amount of flow from the outlet boundary of the at least one cerebral artery by the determined information relating to the volume of the brain tissue segment connected to the at least one cerebral artery.

14. The system of claim 1, wherein:

the patient-specific data includes time-varying data regarding the geometry of the anatomical structure of the patient at different times; and

the at least one computer system is configured to create the three-dimensional model based on the time-varying data and determine the perfusion information based on the time-varying data.

15. The system of claim 1, wherein the at least one computer system is further configured to divide at least the portion of the three-dimensional model representing the brain tissue into the brain tissue segments based on sizes of the cerebral arteries connected to the brain tissue segments.

16. The system of claim 15, wherein the at least one computer system is further configured to determine a size of the at least one brain tissue segment based on a size of at least one of the cerebral arteries connected to the at least one brain tissue segment.

17. The system of claim 1, wherein the at least one computer is further configured to determine information regarding a blood flow characteristic within at least the portion of the cerebral arteries, the blood flow characteristic including at least one of blood flow, blood pressure, or blood velocity at a plurality of locations within at least the portion of the cerebral arteries.

18. A method for determining patient-specific neurovascular information using at least one computer system, the method comprising:

inputting into the at least one computer system patient-specific data regarding a geometry of an anatomical structure of the patient, the anatomical structure including at least a portion of a plurality of cerebral arteries and at least a portion of brain tissue connected to the cerebral arteries;

creating, using the at least one computer system, a three-dimensional model representing the anatomical structure based on the patient-specific data;

dividing, using the at least one computer system, at least a portion of the three-dimensional model representing the brain tissue into segments; and

determining, using the at least one computer system, perfusion information associated with at least one of the brain tissue segments based on the three-dimensional model and a physics-based model relating to the anatomical structure.

19. The method of claim 18, further comprising:

determining, using the at least one computer system, information regarding a blood flow characteristic within at least the portion of the cerebral arteries; and

wherein the determined information regarding the blood flow characteristic includes at least one of blood flow, blood pressure, or blood velocity at a plurality of locations within at least the portion of the cerebral arteries.

20. The method of claim 18, wherein the cerebral arteries include at least one of an extracranial artery or an intracranial artery.

21. The method of claim 18, wherein the three-dimensional model includes at least one of a portion of an aorta, a portion of a carotid artery, or a portion of a vertebral artery.

22. The method of claim 18, wherein the patient-specific data includes imaging data of at least a portion of the anatomical structure, and creating the three-dimensional model includes locating boundaries of lumens of at least the portion of the cerebral arteries using the imaging data.

23. The method of claim 22, wherein the boundaries are located based on changes in intensity values in the imaging data.

24. The method of claim 18, wherein the cerebral arteries include at least one extracranial artery, and the method further comprises:

identifying a plaque within a portion of the three-dimensional model representing the at least one extracranial artery; and

assessing, using the at least one computer system, a vulnerability of the plaque to rupture.

25. The method of claim 18, wherein the perfusion information comprises first perfusion information, and the method further comprises:

modifying the three-dimensional model; and

determining second perfusion information associated with the at least one brain tissue segment based on the modified three-dimensional model.

26. The method of claim 25, wherein the three-dimensional model is modified to simulate at least one of an occlusion of at least one blood vessel or a repair of the occlusion.

27. A non-transitory computer readable medium for use on at least one computer system containing computer-executable programming instructions for performing a method for determining patient-specific neurovascular information, the method comprising:

receiving patient-specific data regarding a geometry of an anatomical structure of the patient, the anatomical structure including at least a portion of a plurality of cerebral arteries and at least a portion of brain tissue connected to the cerebral arteries;

creating a three-dimensional model representing the anatomical structure based on the patient-specific data;

dividing at least a portion of the three-dimensional model representing the brain tissue into segments; and

determining perfusion information associated with at least one of the brain tissue segments based on the three-dimensional model and a physics-based model relating to the anatomical structure.

28. The non-transitory computer readable medium of claim 27, the method further comprising:

determining the perfusion information associated with a plurality of the brain tissue segments based on the three-dimensional model and the physics-based model; and

preparing a three-dimensional simulation of the brain tissue indicating the perfusion information associated with the brain tissue segments.

29. The non-transitory computer readable medium of claim 28, wherein the perfusion information is indicated on the three-dimensional simulation using colors or shading, and variations in the perfusion information are indicated by variations in color or shading.