Probing the diffusion of water and intracellular metabolites to assess white matter microstructure in Duchenne muscular dystrophy

Besides motor impairment, Duchenne muscular dystrophy (DMD) patients experience cognitive and behavioural symptoms. Altered white matter microstructure has been shown with diffusion tensor imaging (DTI) in this population. Here, we combined single volume 1H diffusion-weighted spectroscopy (DWS) and DTI to disentangle intra- and extracellular contributions. Mean apparent diffusion coefficients of N-acetyl aspartate, choline, and creatine were comparable between DMD patients and healthy controls. In the same volume, DMD patients showed increased mean water diffusivity. This suggests that altered white matter microstructure is likely due to extracellular, rather than intracellular, changes.