Method of correcting gradient nonuniformity in gradient motion sensitive imaging applications

Patent metadata

Field	Value
Publication number	US-10545211-B2
Application number	US-201715635898-A
Country	US
Kind code	B2
Filing date	Jun 28, 2017
Priority date	Jun 28, 2017
Publication date	Jan 28, 2020
Grant date	Jan 28, 2020

Abstract

The present disclosure provides a method and system for correcting errors caused by non-linearities in a gradient field profile of a gradient coil in a magnetic resonance imaging (MRI) system. The method includes obtaining a non-linearity tensor at each voxel within the imaging space using a computer model of the gradient coil; correcting motion sensitive encoding using the non-linearity tensor; and generating a corrected image using the corrected motion sensitive encoding.

First claim

What is claimed is:

1. A method of correcting errors caused by non-linearities in a gradient field profile of a gradient coil in a magnetic resonance imaging (MRI) system, the method comprising:
obtaining a non-linearity tensor at each voxel within an imaging space, the non-linearity tensor at each voxel determined from:
a calculated magnetic field gradient at the voxel calculated using a computer model representing conducting pathways of the gradient coil, and
a desired magnetic field gradient at the corresponding voxel;

correcting motion sensitive encoding by calculating a corrected parameter using the non-linearity tensor; and
generating a corrected image from signals from the imaging space using the motion sensitive encoding modified by the corrected parameter.

2. The method of claim 1 , wherein obtaining the non-linearity tensor comprises creating the computer model of the gradient coil, the computer model comprising an element array model of connecting pathways of the gradient coil and other current carrying wires present in the gradient coil.

3. The method of claim 2 , wherein the computer model used to calculate the calculated magnetic field gradient uses equations:

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Assignees

• Harris Chad Tyler
• Curtis Andrew Thomas
• Beatty philip
• Stainsby Jeff Alan
• Synaptive Medical Barbados Inc

Inventors

• Harris Chad Tyler
• Curtis Andrew Thomas
• Beatty philip
• Stainsby Jeff Alan

Classifications

• G01R33/56509 Primary

  due to motion, displacement or flow, e.g. gradient moment nulling (G01R33/567 takes precedence) · CPC title

• G01R33/24

  for measuring direction or magnitude of magnetic fields or magnetic flux · CPC title

• G01R33/5608

  Data processing and visualization specially adapted for MR, e.g. for feature analysis and pattern recognition on the basis of measured MR data, segmentation of measured MR data, edge contour detection on the basis of measured MR data, for enhancing measured MR data in terms of signal-to-noise ratio by means of noise filtering or apodization, for enhancing measured MR data in terms of resolution by means for deblurring, windowing, zero filling, or generation of gray-scaled images, colour-coded images or images displaying vectors instead of pixels (image data processing or generation, in general G06T) · CPC title

• G01R33/56316

  involving phase contrast techniques · CPC title

• G01R33/56572 Primary

  caused by a distortion of a gradient magnetic field, e.g. non-linearity of a gradient magnetic field (G01R33/56509, G01R33/56518, G01R33/56536 take precedence) · CPC title