SPEN single-scanning magnetic resonance imaging spiral sampling and reconstructing method

Abstract

Provided is an SPEN (spatiotemporally-encoded) single-scanning magnetic resonance imaging spiral sampling and reconstructing method, relating to a magnetic resonance imaging method. 90 DEG linear scanning pulses and 180 DEG linear scanning pulses combine with corresponding SPEN gradients, and in a trigger period, protons in a space spin to obtain a quadratic phase relevant with a spatial position; in a sampling period, a spiral sampling gradient after optimization collets data, and obtains spatial domain magnetic resonance imaging data with T2*weighting in a superfast speed; and finally, spiral sampling data are reconstructed through a specific grid algorithm and a super-resolution reconstructing method based on compression perception, so as to obtain super-resolution high quality magnetic resonance images. The method greatly improves the image quality of SPEN single-scanning imaging, and provides a great imaging tool for the fields requiring superfast imaging.

Description

technical field [0001] The invention relates to a magnetic resonance imaging method, in particular to a helical sampling and reconstruction method based on a time-space coded single-scan magnetic resonance imaging. Background technique [0002] In magnetic resonance imaging, increasing the imaging speed or improving the imaging resolution within a fixed time is always pursued by people. Ultra-fast imaging technology plays an important role in some experiments that require high time resolution, such as functional MRI (fMRI) [1-4] , free-breathing heart imaging [5,6] And some high-dimensional experiments such as diffusion tensor imaging (diffusion tensor imaging, DTI) [7-9] . Among many ultra-fast methods, single-scan echo planar imaging (EPI) has become the most popular ultra-fast imaging technology due to its high time resolution. [10-12] . It is well known that echo-planar imaging can fill the entire k-space by sampling through a series of echo train gradients with one...

AI Technical Summary

Problems solved by technology

However, the current spatio-temporal coding single-scan ultra-fast imaging method still has the following defects: First, the fast-switching positive and negative gradient echo chains are used for data acquisition in the sampling stage, which requires high hardware equipment, and its images are easily affected by eddy currents. the impact of the effect; [19,20] Second, due to T 2 Due to the influence of relaxation, the number of sampling points cannot be too much, which limits the inherent spatial resolution of the image; [21] Third, due to the large number of points required for full sampling of space-time coding ultra-fast imaging, the usual number of sampling points cannot satisfy the Nyquist sampling law, resulting in aliasing artifacts in the reconstructed image [18]

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