Determining Functional Severity of Stenosis

• US 20140249399A1
• Filed: 02/14/2014
• Published: 09/04/2014
• Est. Priority Date: 03/04/2013
• Status: Active Grant

• Current Assignee: Siemens Healthineers AG (Siemens AG)
• Original Assignee: Siemens AG
• Inventors: Sharma, Puneet, Kamen, Ali, Comaniciu, Dorin, Schbinger, Max, Scheuering, Michael
• Granted Patent: US 10,052,031 B2
• Time in Patent Office: Days
• US Class Current: 600/408
• CPC Class Codes: A61B 5/0035 adapted for acquisition of images from more than one imaging mode, e.g. combining MRI and optical tomography
• CPC Class Codes: A61B 5/02007 Evaluating blood vessel condition, e.g. elasticity, compliance
• CPC Class Codes: A61B 5/7246 using correlation, e.g. template matching or determination of similarity
• CPC Class Codes: A61B 5/7278 Artificial waveform generation or derivation, e.g. synthesising signals from measured signals A61B5/327 takes precedence
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: A61B 6/032 Transmission computed tomography [CT]
• CPC Class Codes: A61B 6/037 Emission tomography
• CPC Class Codes: A61B 6/466 adapted to display 3D data
• CPC Class Codes: A61B 6/503 for diagnosis of the heart
• CPC Class Codes: A61B 6/504 for diagnosis of blood vessels, e.g. by angiography
• CPC Class Codes: A61B 6/507 for determination of haemodynamic parameters, e.g. perfusion CT
• CPC Class Codes: A61B 6/5217 extracting a diagnostic or physiological parameter from medical diagnostic data
• CPC Class Codes: A61B 6/5235 combining images from the same or different ionising radiation imaging techniques, e.g. PET and CT
• CPC Class Codes: A61B 8/06 Measuring blood flow measuring volume flow in general G01F, e.g. G01F1/66, G01F1/72; measuring speed of fluids in general G01P5/00
• CPC Class Codes: A61B 8/463 characterised by displaying multiple images or images and diagnostic data on one display composite display in devices for short-range imaging with acoustic waves G01S7/52074
• CPC Class Codes: A61B 8/466 adapted to display 3D data 3D imaging and stereoscopic displays in devices for short-range imaging with acoustic waves G01S15/8993 and G01S7/52068, respectively; 3D image rendering G06T15/00; manipulating 3D models for computer graphics G06T19/00
• CPC Class Codes: A61B 8/565 involving data transmission via a network
• CPC Class Codes: G01R 33/56366 Perfusion imaging
• CPC Class Codes: G06T 2207/10104 Positron emission tomography [PET]
• CPC Class Codes: G06T 2207/10108 Single photon emission computed tomography [SPECT]
• CPC Class Codes: G06T 2207/30048 : Heart; Cardiac
• CPC Class Codes: G06T 2207/30101 : Blood vessel; Artery; Vein; Vascular
• CPC Class Codes: G06T 7/0012 : Biomedical image inspection
• CPC Class Codes: G16H 50/30 : for calculating health indices; for individual health risk assessment

Abstract

A method for determining functional severity of a stenosis includes: (a) generating a simulated perfusion map from a calculated blood flow; (b) comparing the simulated perfusion map to a measured perfusion map to identify a degree of mismatch therebetween, the measured perfusion map representing perfusion in a patient; (c) modifying a parameter in a model used in calculating the blood flow when the degree of mismatch meets or exceeds a predefined threshold; (d) computing a hemodynamic quantity from the simulated perfusion map when the degree of mismatch is less than the predefined threshold, the hemodynamic quantity being indicative of the functional severity of the stenosis; and (e) displaying the hemodynamic quantity. Systems for determining functional severity of a stenosis are described.

Claims

1. A computer-implemented method for determining functional severity of a stenosis, the method comprising:

generating, by a processor, a simulated perfusion map from a calculated blood flow;

comparing, by the processor, the simulated perfusion map to a measured perfusion map to identify a degree of mismatch therebetween, the measured perfusion map representing perfusion in a patient;

modifying, by the processor, a parameter in a model used in calculating the blood flow when the degree of mismatch meets or exceeds a predefined threshold;

computing, by the processor, a hemodynamic quantity from the simulated perfusion map when the degree of mismatch is less than the predefined threshold, the hemodynamic quantity being indicative of the functional severity of the stenosis; and

displaying the hemodynamic quantity.

2. The computer-implemented method of claim 1 further comprising:

generating, by the processor, an anatomical model of a coronary vessel and of at least a portion of a myocardium based on medical imaging data acquired from a patient.

3. The computer-implemented method of claim 2 wherein the medical imaging data comprises magnetic resonance data, computed tomography data, positron emission tomography data, single photon emission tomography data, ultrasound data, angiographic data, x-ray data, or a combination thereof.

4. The computer-implemented method of claim 2 wherein the anatomical model comprises a three-dimensional perfusion map, a two-dimensional polar perfusion map, or a combination thereof.

5. The computer-implemented method of claim 2 further comprising:

partitioning, by the processor, the anatomical model into a plurality of perfusion territories.

6. The computer-implemented method of claim 5 wherein the anatomical model is partitioned into 17 segments.

7. The computer-implemented method of claim 1 further comprising:

applying, by the processor, a boundary condition at a boundary point of the coronary vessel.

8. The computer-implemented method of claim 7 wherein the boundary point comprises an outlet.

9. The computer-implemented method of claim 7 wherein the boundary condition is derived from perfusion data obtained from the measured perfusion map.

10. The computer-implemented method of claim 7 wherein the boundary condition is obtained via allometric scaling.

11. The computer-implemented method of claim 1 further comprising:

performing, by the processor, a Computational Fluid Dynamics (CFD) computation to obtain the blood flow and a pressure.

12. The computer-implemented method of claim 1 wherein the measured perfusion map is obtained via CT perfusion scanning, MR perfusion scanning, NM perfusion scanning, or a combination thereof.

13. The computer-implemented method of claim 1 wherein the measured perfusion map is derived at least in part from single photo emission computed tomography (SPECT) data, positron emission tomography (PET) data, or a combination thereof.

14. The computer-implemented method of claim 1 wherein the stenosis comprises a coronary stenosis, a cerebral artery stenosis, or a combination thereof.

15. The computer-implemented method of claim 1 wherein the parameter in the model comprises a boundary condition parameter.

16. The computer-implemented method of claim 1 wherein the hemodynamic quantity is computed from a blood flow value and/or a pressure value, and wherein the blood flow value and the pressure value are derived from the simulated perfusion map.

17. The computer-implemented method of claim 1 wherein the hemodynamic quantity comprises fractional flow reserve (FFR), hyperemic stenosis resistance (HSR), index of myocardial resistance (IMR), or a combination thereof.

18. A system for determining functional severity of a stenosis, the system comprising:

a processor;

a non-transitory memory coupled to the processor;

first logic stored in the memory and executable by the processor to cause the processor to generate a simulated perfusion map from a calculated blood flow;

second logic stored in the memory and executable by the processor to cause the processor to compare the simulated perfusion map to a measured perfusion map to identify a degree of mismatch therebetween, the measured perfusion map representing perfusion in a patient;

third logic stored in the memory and executable by the processor to cause the processor to modify a parameter in a model used in calculating the blood flow when the degree of mismatch meets or exceeds a predefined threshold; and

fourth logic stored in the memory and executable by the processor to cause the processor to compute a hemodynamic quantity from the simulated perfusion map when the degree of mismatch is less than the predefined threshold, the hemodynamic quantity being indicative of the functional severity of the stenosis.

19. The system of claim 18 further comprising:

fifth logic stored in the memory and executable by the processor to cause the processor to generate an anatomical model of a coronary vessel and of at least a portion of a myocardium based on medical imaging data acquired from a patient;

sixth logic stored in the memory and executable by the processor to cause the processor to partition the anatomical model into a plurality of perfusion territories;

seventh logic stored in the memory and executable by the processor to cause the processor to apply a boundary condition at a boundary point of the coronary vessel;

eighth logic stored in the memory and executable by the processor to cause the processor to perform a CFD computation to obtain the blood flow and a pressure; and

ninth logic stored in the memory and executable by the processor to cause the processor to display the hemodynamic quantity.

20. In a non-transitory computer readable storage medium having stored therein data representing instructions executable by a programmed processor for computing a hemodynamic quantity, the storage medium comprising instructions for:

generating a simulated perfusion map from a calculated blood flow;

comparing the simulated perfusion map to a measured perfusion map to identify a degree of mismatch therebetween, the measured perfusion map representing perfusion in a patient;

modifying a parameter in a model used in calculating the blood flow when the degree of mismatch meets or exceeds a predefined threshold;

computing a hemodynamic quantity from the simulated perfusion map when the degree of mismatch is less than the predefined threshold, the hemodynamic quantity being indicative of the functional severity of the stenosis; and

displaying the hemodynamic quantity.