Image processing and patient-specific modeling of blood flow
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.
1. A method for non-invasive assessment of an arterial stenosis, comprising:
receiving medical imaging data pertaining to a patient;
segmenting a plurality of mesh candidates for an anatomical model of an artery including a stenosis region of the patient from the received medical imaging data;
computing a hemodynamic index for the stenosis region in each of the plurality of mesh candidates, wherein computing the hemodynamic index comprises simulating blood flow and pressure in each of the plurality of mesh candidates for the artery of the patient, and computing a fractional flow reserve value for the stenosis region in each of the plurality of mesh candidates based on the blood flow and pressure simulations; and
determining whether a variation among values of the hemodynamic index for the stenosis region in each of the plurality of mesh candidates is significant with respect to a threshold associated with a clinical decision regarding the stenosis region.
2. The method as recited in claim 1 , wherein segmenting a plurality of mesh candidates for an anatomical model of an artery including a stenosis region of a patient from medical imaging data comprises:
segmenting the artery from the medical imaging data to generate the anatomical model;
determining one or more candidate locations for each vertex among a plurality of vertices of the anatomical model; and
generating the plurality of mesh candidates based on the one or more candidate locations.
3. The method as recited in claim 2 , wherein generating the plurality of mesh candidates based on the one or more candidate locations comprises:
generating the plurality of mesh candidates by enforcing a plurality of connection rules for connecting the plurality of candidate locations of neighboring vertices of the anatomical model, wherein each of the plurality of connection rules results in a corresponding mesh candidate.
4. The method as recited in claim 3 , wherein generating the plurality of mesh candidates based on the one or more candidate locations further comprises:
projecting each of the plurality of mesh candidates onto a learned shape space of the artery using an active shape model.
5. The method as recited in claim 1 , wherein determining whether a variation among values of the hemodynamic index for the stenosis region in each of the plurality of mesh candidates is significant with respect to a threshold associated with a clinical decision regarding the stenosis region comprises:
determining whether the variation among values of the hemodynamic index for the stenosis region in each of the plurality of mesh candidates is entirely below the threshold for the clinical decision or is entirely above the threshold for the clinical decision.
6. The method as recited in claim 1 , further comprising:
in response to determining that the variation among values is not significant, displaying results of the hemodynamic index without receiving user input.
7. The method as recited in claim 1 , further comprising:
in response to determining that the variation among values is significant:
displaying at least one of the plurality of mesh candidates; and
receiving user input to select and/or edit the at least one of the plurality of mesh candidates.
8. The method as recited in claim 7 , wherein displaying at least one of the plurality of mesh candidates comprises:
determining a cross-sectional area of one or more mesh candidates of the plurality of mesh candidates.
9. The method as recited in claim 7 , wherein displaying at least one of the plurality of mesh candidates comprises:
simultaneously displaying two or more mesh candidates of the plurality of mesh candidates.
10. The method as recited in claim 7 , wherein displaying at least one of the plurality of mesh candidates comprises:
displaying mesh candidates of the plurality of mesh candidates having a value of the hemodynamic index for the stenosis region above the threshold on a first portion of a display; and
displaying mesh candidates of the plurality of mesh candidates having the value of the hemodynamic index for the stenosis region below the threshold on a second portion of the display.
11. A computer system for non-invasive assessment of an arterial stenosis, comprising:
a memory having processor-readable instructions stored therein; and
a processor configured to access the memory and execute the processor-readable instructions, which when executed by the processor configures the processor to perform a plurality of functions, including functions to:
receive medical imaging data pertaining to a patient;
segment a plurality of mesh candidates for an anatomical model of an artery including a stenosis region of the patient from the received medical imaging data;
compute a hemodynamic index for the stenosis region in each of the plurality of mesh candidates, wherein computing the hemodynamic index comprises simulating blood flow and pressure in each of the plurality of mesh candidates for the artery of the patient, and computing a fractional flow reserve value for the stenosis region in each of the plurality of mesh candidates based on the blood flow and pressure simulations; and
determine whether a variation among values of the hemodynamic index for the stenosis region in each of the plurality of mesh candidates is significant with respect to a threshold associated with a clinical decision regarding the stenosis region.
12. The computer system as recited in claim 11 , wherein the functions to segment a plurality of mesh candidates for an anatomical model of an artery including a stenosis region of a patient from medical imaging data comprises functions to:
segment the artery from the medical imaging data to generate the anatomical model;
determine one or more candidate locations for each vertex among a plurality of vertices of the anatomical model; and
generate the plurality of mesh candidates based on the one or more candidate locations.
13. The computer system as recited in claim 12 , wherein the functions to generate the plurality of mesh candidates based on the one or more candidate locations comprises functions to:
generate the plurality of mesh candidates by enforcing a plurality of connection rules for connecting the plurality of candidate locations of neighboring vertices of the anatomical model, wherein each of the plurality of connection rules results in a corresponding mesh candidate.
14. The computer system as recited in claim 13 , wherein the functions to generate the plurality of mesh candidates based on the one or more candidate locations further comprises functions to:
project each of the plurality of mesh candidates onto a learned shape space of the artery using an active shape model.
15. The computer system as recited in claim 11 , wherein the functions to determine whether a variation among values of the hemodynamic index for the stenosis region in each of the plurality of mesh candidates is significant with respect to a threshold associated with a clinical decision regarding the stenosis region comprises functions to:
functions to determine whether the variation among values of the hemodynamic index for the stenosis region in each of the plurality of mesh candidates is entirely below the threshold for the clinical decision or is entirely above the threshold for the clinical decision.
16. The computer system as recited in claim 11 , wherein the plurality of functions performed by the processor when executing the processor-readable instructions further includes functions to:
in response to determining that the variation among values is not significant, display results of the hemodynamic index without receiving user input.
17. The computer system as recited in claim 11 , wherein the plurality of functions performed by the processor when executing the processor-readable instructions further includes functions to:
in response to determining that the variation among values is significant:
display at least one of the plurality of mesh candidates; and
receive user input to select and/or edit the at least one of the plurality of mesh candidates.
18. A non-transitory computer readable medium storing computer program instructions for non-invasive assessment of an arterial stenosis, the computer program instructions when executed by a processor cause the processor to perform operations comprising:
receiving medical imaging data pertaining to a patient;
segmenting a plurality of mesh candidates for an anatomical model of an artery including a stenosis region of the patient from the received medical imaging data;
computing a hemodynamic index for the stenosis region in each of the plurality of mesh candidates, wherein computing the hemodynamic index comprises simulating blood flow and pressure in each of the plurality of mesh candidates for the artery of the patient, and computing a fractional flow reserve value for the stenosis region in each of the plurality of mesh candidates based on the blood flow and pressure simulations; and
determining whether a variation among values of the hemodynamic index for the stenosis region in each of the plurality of mesh candidates is significant with respect to a threshold associated with a clinical decision regarding the stenosis region.
19. The non-transitory computer readable medium as recited in claim 18 , wherein segmenting a plurality of mesh candidates for an anatomical model of an artery including a stenosis region of a patient from medical imaging data comprises:
segmenting the artery from the medical imaging data to generate the anatomical model;
determining one or more candidate locations for each vertex among a plurality of vertices of the anatomical model; and
generating the plurality of mesh candidates based on the one or more candidate locations.
20. The non-transitory computer readable medium as recited in claim 18 , the operations further comprising:
in response to determining that the variation among values is not significant, displaying results of the hemodynamic index without receiving user input.
21. The non-transitory computer readable medium as recited in claim 18 , the operations further comprising:
in response to determining that the variation among values is significant:
displaying at least one of the plurality of mesh candidates; and
receiving user input to select and/or edit the at least one of the plurality of mesh candidates.
22. The non-transitory computer readable medium as recited in claim 21 , wherein displaying at least one of the plurality of mesh candidates comprises:
determining a cross-sectional area of one or more mesh candidates of the plurality of mesh candidates.