Susceptibility-weighted imaging provides insight into white matter damage in amyotrophic lateral sclerosis

Background: Amyotrophic lateral sclerosis (ALS) is a fatal, progressive neurodegenerative disorder, characterised by widespread white matter damage. There is growing evidence that disturbances in iron metabolism contribute to white matter alterations. Materials & Methods: We analysed the data of susceptibility-weighted imaging (SWI) of white matter in a cohort of 27 patients with ALS and 30 healthy age-matched controls. Results: Signal alterations were found on SWI in the corpus callosum; along the corticospinal tract (subcortical motor cortex, posterior limb of the internal capsule and brainstem levels) and in the subgyral regions of frontal, parietal, temporal, occipital and limbic lobes. Alterations of white matter in the corpus callosum correlated with disease severity as assessed by the revised ALS functional rating scale. Conclusion: SWI is capable of indicating iron and myelin disturbances in white matter of ALS patients. The SWI patterns observed in this study suggest that widespread alterations due to iron disturbances occur in patients with ALS and correlate with disease severity.