"The effect of intra-scan motion on AI reconstructions in MRI"

Laurens Beljaards, Nicola Pezzotti, Christophe Schülke, Matthias J.P. van Osch and Marius Staring

Abstract

MRI can be accelerated via (AI-based) reconstruction by undersampling k-space. Current methods typically ignore intra-scan motion, although even a few millimeters of motion can introduce severe blurring and ghosting artifacts that necessitate reacquisition. In this short paper we investigate the effects of rigid-body motion on AI-based reconstructions. Leveraging the Bloch equations we simulate motion corrupted MRI acquisitions with a linear interleaved scanning protocol including spin history effects, and investigate i) the effect on reconstruction quality, and ii) if this corruption can be mitigated by introducing motion-corrupted data during training. We observe an improvement from 0.787 to 0.844 in terms of SSIM when motion-corrupted brain data is included during training, demonstrating that training with motion-corrupted data can partially compensate for motion corruption. Inclusion of spin-history effects did not influence the results.

BibTeX entry