Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method for correcting gray distortion of nuclear magnetic resonance image

A technology of nuclear magnetic resonance image and gray scale distortion, applied in the direction of measuring magnetic variables, measuring devices, instruments, etc., can solve the problems of impossible real-time image reconstruction, etc., and achieve the effect of improving reliability and imaging quality

Active Publication Date: 2014-03-12
JIANGSU MAGSPIN INSTR
View PDF4 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the calculation time of reconstruction will increase by N / log2N times compared with the usual FFT method, making real-time image reconstruction impossible

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for correcting gray distortion of nuclear magnetic resonance image
  • Method for correcting gray distortion of nuclear magnetic resonance image
  • Method for correcting gray distortion of nuclear magnetic resonance image

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0015] In order to make the purpose, technical solution and advantages of the present invention clearer, the method for correcting the gray scale distortion of the nuclear magnetic resonance image of the present invention will be described in detail below.

[0016] In MRI theory, the image space ( ) and k-space ( ) are related by Fourier transform. After the scanning object is excited by the rf pulse, the three-dimensional gradient space encoding is added to generate an oscillating signal. The three-dimensional Fourier transform can be written as:

[0017]

[0018]

[0019] in, is the signal in k-space, is the scan object spin density in image space, is the image grayscale in the final image space. The three time function components of k can be obtained by integrating their respective gradient components:

[0020]

[0021] in, is a constant, is the gradient component.

[0022] In standard MRI procedures, time-domain signals are acquired at a uniform v...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a method for correcting gray distortion of a nuclear magnetic resonance image. The method comprises the following steps that: spherical-harmonic expansion is performed on a nonlinear gradient field so as to obtain a linear term and a higher-order nonlinear term; the heterogeneity of the gradient field can be obtained through conventional fast Fourier transform (FFT); a heterogeneous mapping relationship between the geometric position and brightness of the image is obtained; a weighted coefficient between the nonlinearity of the gradient field and the gray distortion of the image; and therefore, the correction of the gray distortion of the image can be accomplished. Compared with the prior art, the method for correcting the gray distortion of the nuclear magnetic resonance image of the invention can quickly realize the correction of the gray distortion of the nuclear magnetic resonance image, and therefore, imaging quality and the reliability of clinical diagnosis can be improved, and the method has important significance in the nuclear magnetic resonance imaging field.

Description

technical field [0001] The invention relates to nuclear magnetic resonance imaging, in particular to a method for correcting the gray scale distortion of the nuclear magnetic resonance image. Background technique [0002] In MRI systems, image quality depends on the accuracy of the spatial encoding of the imaged object. Stereotaxic brain surgery, brain atrophy and longitudinal measurement of functional brain imaging, among others, use image deformation and correspondingly magnetic field homogeneity as decisive factors. The magnetic field non-uniformity that can cause image gray level non-uniformity includes electromagnetic eddy current, gradient non-uniformity, and B0 and B1 non-uniformity. [0003] The development trend of gradients in recent years is characterized by short-cavity designs and high-speed flipping, but these designs encounter the problem of thermal stimulation of nerve endings caused by large flipping currents. Especially in some applications such as EPI (e...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): G01R33/565
Inventor 赵华炜
Owner JIANGSU MAGSPIN INSTR
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com