Comprehensive cardiovascular analysis with volumetric phase-contrast MRI

Patent metadata

Field	Value
Publication number	US-10698061-B2
Application number	US-201916654276-A
Country	US
Kind code	B2
Filing date	Oct 16, 2019
Priority date	Jul 7, 2011
Publication date	Jun 30, 2020
Grant date	Jun 30, 2020

Abstract

Processing techniques of volumetric anatomic and vector field data from volumetric phase-contrast MRI on a magnetic resonance imaging (MRI) system are provided to evaluate the physiology of the heart and vessels. This method includes the steps of: (1) correcting for phase-error in the source data, (2) visualizing the vector field superimposed on the anatomic data, (3) using this visualization to select and view planes in the volume, and (4) using these planes to delineate the boundaries of the heart and vessels so that measurements of the heart and vessels can be accurately obtained.

First claim

What is claimed is:

1. A computer-implemented method of processing volumetric phase-contrast magnetic resonance imaging (MRI) data to evaluate the physiology of a heart and vessels, the method comprising:
(a) obtaining the volumetric phase-contrast (MRI) data from a magnetic resonance imaging system, the volumetric phase-contrast (MRI) data comprises volumetric anatomic data for a plurality of time points and vector field data for the plurality of time points;
(b) correcting volumetric phase-error by at least:
calculating parameters for at least three spatial dimensions of a volumetric phase-error model that is representative of phase-offset error across the plurality of time points by at least combining volumetric-phase contrast MRI data of the plurality of time points; and
applying the volumetric phase-error model to the volumetric-phase contrast MRI data for each time point of the plurality of time points, wherein applying the volumetric phase-error model includes applying a same set of calculated parameters of the volumetric phase-error model to the volumetric-phase contrast MRI data for each time point of the plurality of time points; and

(c) displaying on a display the corrected volumetric-phase contrast MRI data by superimposing the vector field data on the volumetric anatomic data.

2. The method of claim 1 , wherein the volumetric phase-error correction comprises computing multiple image filters from a combination of signal intensity and the vector field data for selecting static tissue to be used in a calculation of parameters of the volumetric phase-error model.

3. The method of claim 1 , wherein the volumetric phase-error correction comprises selecting and excluding spatially-wrapped data from data used in a calculation of parameters of the volumetric phase-error model.

4. The method of claim 1 , wherein the displaying comprises multiplanar and volumetric field fusion.

5. A method of operation in at least one component of a medical imaging system that employs volumetric phase-contrast magnetic resonance imaging (MRI) data, the method comprising:
rendering anatomic images via a computer;
superimposing vector field data on the rendered anatomic images by the computer;
receiving at least one user input specifying a range of input values via a user interface, the at least one user input is in the form of a signal indicative of a position of a slider icon along a slider bar, the slider icon selectively movable between a start position and an end position; and
controlling an opacity of the superimposed vector field data based at least in part on a value of the superimposed vector field data relative to the received at least one user input, wherein the opacity of the superimposed vector field is controlled to be a first opacity value as a result of the value being below the range of input values, the opacity of the superimposed vector field is controlled to be between the first opacity value and a second opacity value as a result of the value within the range of input values, the opacity of the superimposed vector field is controlled to be the second opacity value greater than the first opacity value as a result of the value being above the range of input values.

6. The method of claim 5 , wherein the position of the slider icon controls a number of parameters of a transfer function which assigns one of a plurality of colors to each voxel of a plurality of voxels based on a velocity associated with the respective voxel.

7. The method of claim 5 , wherein receiving at least one user input via a user interface includes receiving a signal indicative of a position of a slider icon along a slider bar with a variable width and start position.

8. The method of claim 5 , further comprising applying a mask based solely on signal magnitude.

9. The method of claim 5 , further comprising applying a mask based on a product of signal magnitude and speed.

10. The method of claim 5 , further comprising generating a running tabulation of a peak signal magnitude encountered in each of a plurality of volume-rendering projections.

11. The method of claim 5 , further comprising applying velocity-weighting to increase conspicuity of high-velocity data.

12. A computer that employs volumetric phase-contrast magnetic resonance imaging (MRI) data, wherein in use the computer:
renders anatomic images via a computer;
superimposes vector field data on the rendered anatomic images by the computer;
receives at least one user input specifying a range of input values via a user interface, the at least one user input is in the form of a signal indicative of a position of a slider icon along a slider bar; and
controls an opacity of the superimposed vector field data based at least in part on a value of the superimposed vector field data relative to the received at least one user input, wherein the opacity of the superimposed vector field is controlled to be a first opacity value as a result of the value being below the range of input values, the opacity of the superimposed vector field is controlled to be between the first opacity value and a second opacity value as a result of the value within the range of input values, the opacity of the superimposed vector field is controlled to be the second opacity value greater than the first opacity value as a result of the value being above the range of input values, a start position of the slider icon corresponding to a minimum opacity of the superimposed vector field data, and an end position of the slider icon corresponding corresponds to a maximum opacity of the superimposed vector field data.

13. The computer of claim 12 , wherein the position of the slider icon controls a number of parameters of a transfer function which assigns one of a plurality of colors to each voxel of a plurality of voxels based on a velocity associated with the respective voxel.

14. The computer of claim 12 , which in use further applies a mask based solely on signal magnitude.

15. The computer of claim 12 , which in use further applies a mask based on a product of signal magnitude and speed.

16. The computer of claim 12 , which in use further generates a running tabulation of a peak signal magnitude encountered in each of a plurality of volume-rendering projections.

17. The computer of claim 12 , which in use further applies velocity-weighting to increase conspicuity of high-velocity data.

18. A method of processing volumetric phase-contrast magnetic resonance imaging (MRI) data to evaluate the physiology of a heart and vessels, the method comprising:
(a) obtaining the volumetric phase-contrast (MRI) data, wherein the volumetric phase-contrast (MRI) data comprises volumetric anatomic data for a plurality of time points and vector field data for the plurality of time points;
(b) correcting volumetric phase-error by at least:
calculating parameters for at least three spatial dimensions of a volumetric phase-error model that is representative of phase-offset error across the plurality of time points, and
applying the volumetric phase-error model to the volumetric-phase contrast MRI data for each time point of the plurality of time points;

(c) displaying on a display the corrected volumetric-phase contrast MRI data by superimposing the vector field data on the volumetric anatomic data, the displaying including:
receiving a first input specifying a first plane for a first time point of the plurality of time points;
receiving a second input specifying a second plane for a second time point of the plurality of time points;
generating a set of planes for time

Assignees

• Univ Leland Stanford Junior

Inventors

• Hsiao Albert
• Vasanawala Shreyas S
• Alley Marcus T

Classifications

• G06T7/13

  Edge detection · CPC title

• A61B5/0263

  using NMR · CPC title

• A61B5/055

  involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging · CPC title

• G01R33/56518

  due to eddy currents, e.g. caused by switching of the gradient magnetic field · CPC title

• G01R33/56545

  caused by finite or discrete sampling, e.g. Gibbs ringing, truncation artefacts, phase aliasing artefacts · CPC title