Motion corrected MRI with DISORDER: Distributed and Incoherent Sample Orders for Reconstruction Deblurring using Encoding Redundancy

TL;DR

This paper introduces DISORDER, a method for motion correction in MRI that leverages encoding redundancy and incoherent sampling to enable retrospective correction of rigid-body head motion without external sensors, improving pediatric scan quality.

Contribution

The novel approach uses distributed and incoherent sampling orders to achieve motion tolerance in MRI, eliminating the need for external motion tracking devices.

Findings

Simulations show effective inter-shot motion correction under various conditions.

In-vivo experiments demonstrate successful correction of controlled motion.

High-quality results achieved in clinical pediatric MRI scans with motion artifacts.

Abstract

Purpose: To enable rigid-body motion tolerant parallel volumetric magnetic resonance imaging by retrospective head motion correction on a variety of spatio-temporal scales and imaging sequences. Theory and methods: Tolerance against rigid-body motion is based on distributed and incoherent sampling orders for boosting a joint retrospective motion estimation and reconstruction framework. Motion resilience stems from the encoding redundancy in the data, as generally provided by the coil array. Hence, it does not require external sensors, navigators or training data, so the methodology is readily applicable to sequences using 3D encodings. Results: Simulations are performed showing full inter-shot corrections for usual levels of in-vivo motion, large number of shots, standard levels of noise and moderate acceleration factors. Feasibility of inter- and intra-shot corrections is shown under controlled motion in-vivo. Practical efficacy is illustrated by high quality results in most corrupted of 208 volumes from a series of 26 clinical pediatric examinations collected using standard protocols. Conclusion: The proposed framework addresses the rigid motion problem in volumetric anatomical brain scans with sufficient encoding redundancy which has enabled reliable pediatric examinations without sedation.