Meeting Banner
Abstract #2696

Characterising the impact of distortion correction in high-resolution 3D GRE R2* mapping at 7T.

Barbara Dymerska1, Oliver Josephs1, and Martina Callaghan1
1Wellcome Centre for Human Neuroimaging, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom


R2*-mapping delivers quantitative information about tissue microstructure. We investigate the scale of image distortions in high-resolution, bipolar, multi-echo GRE acquisitions at 7T and their effects on R2*-mapping. We study reduction in variance by applying field map-based distortion correction while also considering the confounding effect of local smoothing. We show that for regions with signal displacement > 0.5 voxels the reduction in variance comes largely, not from smoothing, but from the appropriate repositioning of the tissue signal. Therefore, correcting distortions, also in sub-voxel regime, improves data consistency in bipolar GRE acquisitions, facilitating more robust R2*-mapping in high-resolution laminar studies for instance.

This abstract and the presentation materials are available to members only; a login is required.

Join Here