Method and system for patient-specific modeling of blood flow

• US 10,327,847 B2
• Filed: 08/04/2015
• Issued: 06/25/2019
• Est. Priority Date: 08/12/2010
• Status: Active Grant

• Current Assignee: Heartflow Inc.
• Original Assignee: Heartflow Inc.
• Inventors: Taylor, Charles A.
• Primary Examiner(s): Clow, Lori A.
• Application Number:
  US14/817,499
• Publication Number:
  US 20150339459A1
• Time in Patent Office: 1,421 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 non-transitory computer readable medium having stored thereon a computer program comprising instructions, which, when executed by a computer, cause the computer to perform a method for generating a measure or an indication of inhibition of blood flow, the method comprising:

obtaining volume data or data of a series of images regarding an anatomy of an organ of a patient;

generating, using the obtained volume data or the obtained data of a series of images, a three-dimensional patient-specific tissue model of the organ of the patient;

subdividing the three-dimensional patient-specific tissue model into a first region and a second region;

creating a first patient-specific blood flow model corresponding to the first region of the three-dimensional patient-specific tissue model of the organ;

calculating, using the first patient-specific blood flow model corresponding to the first region of the three-dimensional patient-specific tissue model of the organ, a first blood flow value of perfusion into the first region of the three-dimensional patient-specific tissue model;

creating a second patient-specific blood flow model corresponding to the second region of the three-dimensional patient-specific tissue model of the organ;

calculating, using the second patient-specific blood flow model corresponding to the second region of the three-dimensional patient-specific tissue model of the organ, a second blood flow value of perfusion into the second region of the three-dimensional patient-specific tissue model;

calculating a metric of inhibition of a blood flow in a blood vessel of the patient'"'"'s organ, the metric comprising a ratio of the calculated first blood flow value of perfusion into the first region of the three-dimensional patient-specific tissue model to the calculated second blood flow value of perfusion into the second region of the three-dimensional patient-specific tissue model; and

outputting, to an electronic storage medium or display, the calculated metric of inhibition of the blood flow in the blood vessel of the patient'"'"'s organ.

2. The non-transitory computer readable medium according to claim 1, the method further comprising generating a display of either the first region or the second region with the calculated metric of inhibition of the blood flow in the patient'"'"'s blood vessel.

3. The non-transitory computer readable medium according to claim 2, wherein the method further comprises:

determining, using the obtained volume data or the obtained data of the series of images, blood flow information corresponding to locations in regions different from the first region and the second region;

calculating, for each of the locations, a selected metric of blood flow inhibition using the blood flow information corresponding to the respective location; and

displaying each calculated selected metric of the blood flow inhibition in predetermined hues corresponding to values of the calculated selected measure or the calculated selected indication.

4. The non-transitory computer readable medium according to claim 1, wherein the organ includes a heart of the patient, and the calculated metric includes a fractional flow reserve.

5. The non-transitory computer readable medium according to claim 1, wherein the first region includes a stenosed blood vessel in the organ, and the second region includes an unstenosed blood vessel in the organ.

6. The non-transitory computer readable medium according to claim 5, wherein the first blood flow value of perfusion into the first region of the three-dimensional patient-specific tissue model and the second blood flow value of perfusion into the second region of the three-dimensional patient-specific tissue model include blood flow volumes of a specific cardiac phase of the heart or average blood flow volumes of all cardiac phases.

7. The non-transitory computer readable medium according to claim 1, wherein the obtained volume data includes data regarding nuclear medicine tomography or X-ray computed tomography, and the obtained data of the series of images include data regarding X-ray diagnostic imaging.

8. The non-transitory computer readable medium according to claim 7, wherein the first region includes a downstream region from a stenosed portion in a myocardial region dominated by a stenosed blood vessel.

9. The non-transitory computer readable medium according to claim 1, wherein the method further comprises:

determining an error in each of the first blood flow value of perfusion into the first region of the three-dimensional patient-specific tissue model and the second blood flow value of perfusion into the second region of the three-dimensional patient-specific tissue model; and

modifying the first blood flow value of perfusion into the first region of the three-dimensional patient-specific tissue model and the second blood flow value of perfusion into the second region of the three-dimensional patient-specific tissue model by performing a correction until the error in each of the first blood flow value of perfusion into the first region of the three-dimensional patient-specific tissue model and the second blood flow value of perfusion into the second region of the three-dimensional patient-specific tissue model is below a predetermined threshold.

10. The non-transitory computer readable medium of claim 1, wherein the first patient-specific blood flow model differs from the second patient-specific blood flow model.

11. A medical image processing method comprising:

obtaining volume data or data of a series of images regarding an anatomy of an organ of a patient;

generating, using the obtained volume data or the obtained data of a series of images, a three-dimensional patient-specific tissue model of the organ of the patient;

subdividing the three-dimensional patient-specific tissue model into a first region and a second region;

creating a first patient-specific blood flow model corresponding to the first region of the three-dimensional patient-specific tissue model of the organ;

calculating, using the first patient-specific blood flow model corresponding to the first region of the three-dimensional patient-specific tissue model of the organ, a first blood flow value of perfusion into the first region of the three-dimensional patient-specific tissue model;

creating a second patient-specific blood flow model corresponding to the second region of the three-dimensional patient-specific tissue model of the organ;

calculating, using the second patient-specific blood flow model corresponding to the second region of the three-dimensional patient-specific tissue model of the organ, a second blood flow value of perfusion into the second region of the three-dimensional patient-specific tissue model;

calculating a metric of inhibition of a blood flow in a blood vessel of the patient'"'"'s organ, the metric comprising a ratio of the calculated first blood flow value of perfusion into the first region of the three-dimensional patient-specific tissue model to the calculated second blood flow value of perfusion into the second region of the three-dimensional patient-specific tissue model; and

outputting, to an electronic storage medium or display, the calculated metric of inhibition of the blood flow in the blood vessel of the patient'"'"'s organ.

12. The medical image processing method according to claim 11, the method further comprising displaying either the first region or the second region with the calculated metric of inhibition of the blood flow in the patient'"'"'s blood vessel.

13. The medical image processing method according to claim 12, wherein the method further comprises:

determining, using the obtained volume data or the obtained data of the series of images, blood flow information corresponding to locations in regions different from the first region and the second region;

calculating, for each of the locations, a selected metric of blood flow inhibition using the blood flow information corresponding to the respective location; and

displaying each calculated selected metric of the blood flow inhibition in predetermined hues corresponding to values of the calculated selected measure or the calculated selected indication.

14. The medical image processing method according to claim 11, wherein the organ includes a heart of the patient, and the calculated metric includes a fractional flow reserve.

15. The medical image processing method according to claim 11, wherein the first region includes a stenosed blood vessel in the organ, and the second region includes an unstenosed blood vessel in the organ.

16. The medical image processing method according to claim 15, wherein the first blood flow value of perfusion into the first region of the three-dimensional patient-specific tissue model and the second blood flow value of perfusion into the second region of the three-dimensional patient-specific tissue model include blood flow volumes of a specific cardiac phase of the heart or average blood flow volumes of all cardiac phases.

17. The medical image processing method according to claim 11, wherein the obtained volume data includes data regarding nuclear medicine tomography or X-ray computed tomography, and the obtained data of the series of images includes data regarding X-ray diagnostic imaging.

18. The medical image processing method according to claim 11, wherein the method further comprises:

determining an error in each of the first blood flow value of perfusion into the first region of the three-dimensional patient-specific tissue model and the second blood flow value of perfusion into the second region of the three-dimensional patient-specific tissue model; and

modifying the first blood flow value of perfusion into the first region of the three-dimensional patient-specific tissue model and the second blood flow value of perfusion into the second region of the three-dimensional patient-specific tissue model by performing a correction until the error in each of the first blood flow value and the second blood flow value is below a predetermined threshold.

19. The medical image processing method of claim 11, wherein the first patient-specific blood flow model differs from the second patient-specific blood flow model.

20. A medical image processing apparatus configured to execute a method, the method comprising:

obtaining volume data or data of a series of images regarding an anatomy of an organ of a patient;

generating, using the obtained volume data or the obtained data of a series of images, a three-dimensional patient-specific tissue model of the organ of the patient;

subdividing the three-dimensional patient-specific tissue model into a first region and a second region;

creating a first patient-specific blood flow model corresponding to the first region of the three-dimensional patient-specific tissue model of the organ;

calculating, using the patient-specific blood flow model corresponding to the first region of the three-dimensional patient-specific tissue model of the organ, a first blood flow value of perfusion into the first region of the three-dimensional patient-specific tissue model;

creating a second patient-specific blood flow model corresponding to the second region of the three-dimensional patient-specific tissue model of the organ;

calculating, using the second patient-specific blood flow model corresponding to the second region of the three-dimensional patient-specific tissue model of the organ, a second blood flow value of perfusion into the second region of the three-dimensional patient-specific tissue model;

calculating a metric of inhibition of a blood flow in a blood vessel of the patient'"'"'s organ, the metric comprising a ratio of the calculated first blood flow value of perfusion into the first region of the three-dimensional patient-specific tissue model to the calculated second blood flow value of perfusion into the second region of the three-dimensional patient-specific tissue model; and

outputting, to an electronic storage medium or display, the calculated metric of inhibition of the blood flow in the blood vessel of the patient'"'"'s organ.