[HTML][HTML] An integrated approach to correction for off-resonance effects and subject movement in diffusion MR imaging

JLR Andersson, SN Sotiropoulos - Neuroimage, 2016 - Elsevier
Neuroimage, 2016Elsevier
In this paper we describe a method for retrospective estimation and correction of eddy
current (EC)-induced distortions and subject movement in diffusion imaging. In addition a
susceptibility-induced field can be supplied and will be incorporated into the calculations in
a way that accurately reflects that the two fields (susceptibility-and EC-induced) behave
differently in the presence of subject movement. The method is based on registering the
individual volumes to a model free prediction of what each volume should look like, thereby …
Abstract
In this paper we describe a method for retrospective estimation and correction of eddy current (EC)-induced distortions and subject movement in diffusion imaging. In addition a susceptibility-induced field can be supplied and will be incorporated into the calculations in a way that accurately reflects that the two fields (susceptibility- and EC-induced) behave differently in the presence of subject movement. The method is based on registering the individual volumes to a model free prediction of what each volume should look like, thereby enabling its use on high b-value data where the contrast is vastly different in different volumes. In addition we show that the linear EC-model commonly used is insufficient for the data used in the present paper (high spatial and angular resolution data acquired with Stejskal–Tanner gradients on a 3 T Siemens Verio, a 3 T Siemens Connectome Skyra or a 7 T Siemens Magnetome scanner) and that a higher order model performs significantly better.
The method is already in extensive practical use and is used by four major projects (the WU-UMinn HCP, the MGH HCP, the UK Biobank and the Whitehall studies) to correct for distortions and subject movement.
Elsevier