Contents

%%%%%%
% This code demonstrates the T2 Shuffling point spread functions (PSF)
% described in the MRM paper,
% "T2 Shuffling: Sharp, Multi-Contrast, Volumetric Fast Spin-Echo Imaging"
%
% The code is provided to demonstrate the method. It is not optimized
% for reconstruction time
%
% Jonathan Tamir <jtamir@eecs.berkeley.edu>
% Jan 04, 2015

addpath src/utils/

normalize_psfs = true;
fignum = 1;

T2vals = [50, 150, 500] * 1e-3; % T2 values to simulate
ETL = 80;
TE = 6e-3;

Simulate exponential decay and plot the PSF for a center-out ordering.

The short-T2 components have a very broad peak, indicating image blur.

randshuffle = false;
psf_1d(T2vals, ETL, TE, randshuffle, normalize_psfs, true, fignum + 0);
ftitle('Center-out ordering (zoom in)', 32);

psf_1d(T2vals, ETL, TE, randshuffle, normalize_psfs, false, fignum + 1);
ftitle('Center-out ordering', 32);

Simulate exponential decay and plot the PSF for a randomly shuffled ordering.

All PSFs are sharp, but short-T2 components have a low peak-to-sidelobe ratio due to incoherent artifacts

randshuffle = true;
psf_1d(T2vals, ETL, TE, randshuffle, normalize_psfs, true, fignum + 2);
ftitle('Randomly shuffled ordering (zoom in)', 32);

psf_1d(T2vals, ETL, TE, randshuffle, normalize_psfs, false, fignum + 3);
ftitle('Randomly shuffled ordering', 32);

Published with MATLAB® R2014a