Image-Based Waveform Parameter Estimation

• US 20150324977A1
• Filed: 05/05/2015
• Published: 11/12/2015
• Est. Priority Date: 05/09/2014
• Status: Active Grant

• Current Assignee: Northwestern University, Siemens Healthineers AG (Siemens AG)
• Original Assignee: Northwestern University, Siemens Medical Solutions USA Incorporated (Siemens AG)
• Inventors: Spottiswoode, Bruce S., Markl, Michael, Magrath, Patrick, Stalder, Aurlien, Gulsun, Mehmet Akif
• Granted Patent: US 9,498,140 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 5/0263 using NMR
• CPC Class Codes: A61B 5/0285 Measuring or recording phase velocity of blood waves
• CPC Class Codes: G06T 2207/10088 Magnetic resonance imaging [MRI]
• CPC Class Codes: G06T 2207/20101 Interactive definition of point of interest, landmark or seed
• CPC Class Codes: G06T 2207/30104 Vascular flow; Blood flow; Perfusion
• CPC Class Codes: G06T 2207/30172 Centreline of tubular or elongated structure
• CPC Class Codes: G06T 7/0012 Biomedical image inspection
• CPC Class Codes: G06T 7/0016 involving temporal comparison
• CPC Class Codes: G06T 7/12 Edge-based segmentation

Abstract

Disclosed herein is a framework for facilitating waveform parameter estimation. In accordance with one aspect, time-based waveforms are generated based on analysis planes positioned along a centerline of the vessel. A surface may be fitted to upslope regions of the waveforms to determine one or more waveform parameters based on intersection of the surface with the upslope regions.

Claims

1. A computer-implemented method of waveform parameter estimation, comprising:

(i) receiving image data of at least one vessel;

(ii) generating time-based waveforms based on analysis planes positioned along a centerline of the vessel;

(iii) fitting surfaces to different subsets of upslope regions of the waveforms to derive local waveform parameters based on intersections of the surfaces with the upslope regions; and

(iv) determining a global waveform parameter based on the local waveform parameters.

2. The method of claim 1 wherein fitting the surfaces to the different subsets of the upslope regions comprises fitting least squares planes to the different subsets of the upslope regions.

3. The method of claim 1 wherein determining the global waveform parameter comprises determine an average value of the local waveform parameters.

4. The method of claim 1 wherein determining the global waveform parameter comprises determining a global pulse wave velocity.

5. A system for waveform parameter estimation, comprising:

a non-transitory memory device for storing computer readable program code, and

a processor in communication with the memory device, the processor being operative with the computer readable program code to perform steps including

(i) receiving image data of at least one vessel;

(ii) generating time-based waveforms based on analysis planes positioned along a centerline of the vessel;

(iii) fitting a surface to upslope regions of the waveforms; and

(iv) determining one or more waveform parameters based on intersection of the surface with the upslope regions.

6. The system of claim 5 wherein the image data comprises four-dimensional flow magnetic resonance image data.

7. The system of claim 5 wherein the vessel comprises a blood vessel.

8. The system of claim 5 wherein the processor is operative with the computer readable program code to extract the centerline of the vessel by automatically detecting the centerline between user-placed seed points.

9. The system of claim 5 wherein the processor is operative with the computer readable program code to generate the time-based waveforms by generating time-based flow waveforms.

10. The system of claim 5 wherein the processor is operative with the computer readable program code to generate the time-based waveforms by generating time-based velocity waveforms.

11. The system of claim 5 wherein the surface comprises a second or higher order polynomial surface.

12. The system of claim 11 wherein the second or higher order polynomial surface is represented by

f(x,t)=A+Bx+Ct+Dx²+Ext+Ft²,

wherein x denotes centerline distance, t denotes time, f(x,t) denotes flow rate, and A, B, C, D, E and F denote parameters extracted from the fitting.

13. The system of claim 5 wherein the surface comprises a twisted plane.

14. The system of claim 5 wherein the processor is operative with the computer readable program code to fit the surface to the upslope regions by fitting multiple surfaces to different subsets of the upslope regions to derive local waveform parameters.

15. The system of claim 14 wherein the processor is operative with the computer readable program code to determine the one or more waveform parameters by deriving a global waveform parameter based on the local waveform parameters.

16. The system of claim 14 wherein the processor is operative with the computer readable program code to fit the surfaces to the subsets of the upslope regions by fitting least square planes to the subsets of the upslope regions.

17. The system of claim 14 wherein the processor is operative with the computer readable program code to determine the one or more waveform parameters by determining a pulse wave velocity.

18. A non-transitory computer readable medium embodying a program of instructions executable by machine to perform steps for patient signal analysis, the steps comprising:

(i) receiving image data of at least one vessel;

(ii) generating time-based waveforms based on analysis planes positioned along a centerline of the vessel;

(iii) fitting a surface to upslope regions of the waveforms; and

(iv) determining one or more waveform parameters based on intersection of the surface with the upslope regions.

19. The non-transitory computer readable medium of claim 18 wherein fitting the surface to the upslope regions of the waveforms comprises fitting a second or higher order polynomial surface to the upslope regions.

20. The non-transitory computer readable medium of claim 18 wherein fitting the surface to the upslope regions of the waveforms comprises fitting a twisted plane to the upslope regions.