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

• US 10,376,317 B2
• Filed: 08/25/2016
• Issued: 08/13/2019
• 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:
  US15/247,231
• Publication Number:
  US 20160364860A1
• Time in Patent Office: 1,083 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 for image processing for predicting a post-stenting blood flow characteristic for a coronary artery stenosis from pre-stenting medical image data, comprising:

determining a patient-specific anatomical model of a patient'"'"'s coronary arteries from the pre-stenting medical image data of the patient;

simulating blood flow through at least a portion of the patient-specific anatomical model of the coronary arteries using a pressure-loss model, wherein the pressure-loss model simulates blood flow through at least a portion of the patient-specific anatomical model;

determining a target stenosis region of the patient-specific anatomical model corresponding to a stenosis in the patient'"'"'s coronary arteries;

determining a change in pressure over the target stenosis region in the patient-specific anatomical model of the coronary arteries based on the simulated blood flow;

simulating the insertion of a stent by widening a coronary artery of the patient-specific anatomical model at the target stenosis region; and

determining at least one predicted post-stenting blood flow characteristic value for the target stenosis region by re-simulating blood flow through the patient-specific anatomical model of the coronary arteries using a pressure-loss model, the at least one predicted post-stenting blood flow characteristic value being used to determine whether to place a stent in the patient.

2. The method of claim 1, wherein simulating blood flow in the patient-specific anatomical model of the coronary arteries using the pressure-loss model comprises:

simulating blood flow in the patient-specific anatomical model of the coronary arteries using a computational analysis of coronary circulation that represents stenosis regions in the patient-specific anatomical model of the coronary arteries with pressure-loss models, wherein the pressure-loss model representing the target stenosis region is modified to simulate the effect of stenting on the target stenosis region.

3. The method of claim 1, wherein the pressure-loss model models amounts of widening to simulate the effect of a stenting procedure on the target stenosis region.

4. The method of claim 1, further comprising:

displaying a prompt requesting a user selection of a stent; and

selecting the pressure-loss model for the target stenosis region based on a received user selection.

5. The method of claim 1, wherein determining at least one predicted post-stenting blood flow characteristic value for the target stenosis region comprises:

determining at least one predicted post-stenting fractional flow reserve (FFR) value for the target stenosis region based on the determined change in pressure over the target stenosis region.

6. The method of claim 1, wherein the target stenosis region is a first target stenosis region and the method further comprises:

repeating the steps of;

simulating blood flow in the patient-specific anatomical model of the coronary arteries using a pressure-loss model that simulates an effect of stenting on a second target stenosis region;

computing a change in pressure over the second target stenosis region in the patient-specific anatomical model of the coronary arteries based on the simulated blood flow; and

determining at least one predicted post-stenting blood flow characteristic value for the second target stenosis region based on the determined pressure-over the second target stenosis region.

7. A method for automated virtual planning of a stenting treatment to treat coronary artery stenoses of a patient, comprising:

determining a patient-specific anatomical model of a patient'"'"'s coronary arteries from medical image data of the patient;

computing pre-stenting fractional flow reserve (FFR) values for a plurality of stenosis regions in the patient-specific anatomical model of the coronary arteries based on simulated blood flow and pressure in the patient-specific anatomical model of the coronary arteries;

determining a plurality of virtual stenting strategies based on the pre-stenting FFR values computed for the plurality of stenosis regions; and

predicting post-stenting FFR values for the plurality of stenosis regions resulting from each of the plurality of virtual stenting strategies, wherein each virtual stenting strategy designates one or more of the stenosis regions to be stented, and for each virtual stenting strategy, the predicted post-stenting FFR values for the plurality of stenosis regions are computed by simulating blood flow in the patient-specific anatomical model of the coronary arteries with a respective pressure-loss model used to compute a post-stenting pressure across each of the one or more of the stenosis regions designated to be stented in that stenting strategy, the respective pressure-loss models corresponding to differing amounts of widening of a coronary artery of the patient-specific anatomical model of the coronary arteries, the predicted post-stenting FFR values being used to place a stent in the patient.

8. The method of claim 7, wherein determining a plurality of virtual stenting strategies based on the pre-stenting FFR values computed for the plurality of stenosis regions comprises:

identifying a stenosis region having an FFR value less than a predetermined threshold and one or more preceding stenosis regions in the patient-specific anatomical model of the coronary arteries to be included in a set target stenosis regions; and

determining the plurality of virtual stenting strategies to include respective virtual stenting strategies that designate each of the target stenosis regions to be stented.

9. The method of claim 8, further comprising:

identifying at least one of the plurality of virtual stenting strategies that results in predicted posting-stenting FFR values less than the predetermined threshold for each of the plurality of stenosis regions.

10. A computer system for image processing for predicting a post-stenting blood flow characteristic for a coronary artery stenosis from pre-stenting medical image data, comprising:

a digital storage device storing instructions that, when executed by a processor, cause the computer system to perform a method for image processing for predicting a post-stenting blood flow characteristic for a coronary artery stenosis from pre-stenting medical image data; and

a processor configured to execute the instructions to perform the method for image processing for predicting a post-stenting blood flow characteristic for a coronary artery stenosis from pre-stenting medical image data, the method comprising;

determining a patient-specific anatomical model of a patient'"'"'s coronary arteries from the pre-stenting medical image data of the patient;

simulating blood flow through at least a portion of the patient-specific anatomical model of the coronary arteries using a pressure-loss model, wherein the pressure-loss model simulates blood flow through at least a portion of the patient-specific anatomical model;

determining a target stenosis region of the patient-specific anatomical model corresponding to a stenosis in the patient'"'"'s coronary arteries;

determining a change in pressure over the target stenosis region in the patient-specific anatomical model of the coronary arteries based on the simulated blood flow;

simulating the insertion of a stent by widening a coronary artery of the patient-specific anatomical model at the target stenosis region; and

determining at least one predicted post-stenting blood flow characteristic value for the target stenosis region by re-simulating blood flow through the patient-specific anatomical model of the coronary arteries using a pressure-loss model, the at least one predicted post-stenting blood flow characteristic value being used to determine whether to place a stent in the patient.

11. The computer system of claim 10, wherein simulating blood flow in the patient-specific anatomical model of the coronary arteries using the pressure-loss model comprises:

simulating blood flow in the patient-specific anatomical model of the coronary arteries using a computational analysis of coronary circulation that represents stenosis regions in the patient-specific anatomical model of the coronary arteries with pressure-loss models, wherein the pressure-loss model representing the target stenosis region is modified to simulate the effect of stenting on the target stenosis region.

12. The computer system of claim 10, wherein the pressure-loss model models amounts of widening to simulate the effect of a stenting procedure on the target stenosis region.

13. The computer system of claim 10, wherein the determining at least one predicted post-stenting blood flow characteristic for the target stenosis region comprises:

determining a predicted post-stenting fractional flow reserve (FFR) value for the target stenosis region based on the determined post-stenting change in pressure over the target stenosis region computed using the pressure-loss model.

14. A non-transitory computer readable medium storing computer program instructions for image processing for predicting a post-stenting blood flow characteristic for a coronary artery stenosis from pre-stenting medical image data, the computer program instructions when executed by a processor cause the processor to perform operations comprising:

determining a patient-specific anatomical model of a patient'"'"'s coronary arteries from the pre-stenting medical image data of the patient;

simulating blood flow through at least a portion of the patient-specific anatomical model of the coronary arteries using a pressure-loss model, wherein the pressure-loss model simulates blood flow through at least a portion of the patient-specific anatomical model;

determining a target stenosis region of the patient-specific anatomical model corresponding to a stenosis in the patient'"'"'s coronary arteries;

determining a change in pressure over the target stenosis region in the patient-specific anatomical model of the coronary arteries based on the simulated blood flow;

simulating the insertion of a stent by widening a coronary artery of the patient-specific anatomical model at the target stenosis region; and

determining at least one predicted post-stenting blood flow characteristic value for the target stenosis region by re-simulating blood flow through the patient-specific anatomical model of the coronary arteries using a pressure-loss model, the at least one predicted post-stenting blood flow characteristic value being used to determine whether to place a stent in the patient.

15. The non-transitory computer readable medium of claim 14, wherein simulating blood flow in the patient-specific anatomical model of the coronary arteries using the pressure-loss model comprises:

simulating blood flow in the patient-specific anatomical model of the coronary arteries using a computational analysis of coronary circulation that represents stenosis regions in the patient-specific anatomical model of the coronary arteries with pressure-loss models, wherein the pressure-loss model representing the target stenosis region is modified to simulate the effect of stenting on the target stenosis region.

16. The non-transitory computer readable medium of claim 14, wherein determining at least one predicted post-stenting blood flow characteristic for the target stenosis region comprises:

determining at least one predicted post-stenting fractional flow reserve (FFR) value for the target stenosis region based on the determined change in pressure over the target stenosis region.

17. The non-transitory computer readable medium of claim 14, wherein the target stenosis region is a first target stenosis region and the operations further comprise:

repeating the operations of simulating blood flow in the patient-specific anatomical model of the coronary arteries using a pressure-loss model that simulates an effect of stenting on a second target stenosis region;

determining a change in pressure over the second target stenosis region in the patient-specific anatomical model of the coronary arteries based on the simulated blood flow; and

determining at least one predicted post-stenting blood flow characteristic value for the target stenosis region based on the computed change in pressure over the target stenosis region.