Journal article

Investigating white matter fibre density and morphology using fixel-based analysis

David A Raffelt, J-Donald Tournier, Robert E Smith, David N Vaughan, Graeme Jackson, Gerard R Ridgway, Alan Connelly



Voxel-based analysis of diffusion MRI data is increasingly popular. However, most white matter voxels contain contributions from multiple fibre populations (often referred to as crossing fibres), and therefore voxel-averaged quantitative measures (e.g. fractional anisotropy) are not fibre-specific and have poor interpretability. Using higher-order diffusion models, parameters related to fibre density can be extracted for individual fibre populations within each voxel ('fixels'), and recent advances in statistics enable the multi-subject analysis of such data. However, investigating within-voxel microscopic fibre density alone does not account for macroscopic differences in the white matter m..

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Awarded by National Health and Medical Research Council (NHMRC) of Australia

Awarded by UK Medical Research Council

Awarded by Wellcome Trust

Awarded by Medical Research Council

Funding Acknowledgements

We are grateful to the National Health and Medical Research Council (NHMRC) (400121) of Australia and the Victorian Government's Operational Infrastructure Support Program for their support. GRR is supported by the UK Medical Research Council [Grant number MR/J014257/2]. The Wellcome Trust Centre for Neuroimaging is supported by core funding from the Wellcome Trust [Grant number 091593/Z/10/Z]. To request access to the underlying research materials please contact the corresponding author.