White matter in the brain degenerates after ischaemic stroke, not only close to the focal lesion but even in the opposite hemisphere, researchers have found.

In their study comparing 104 people with ischaemic stroke with 40 age-matched healthy controls, the investigators, led by researchers from the Florey Institute of Neuroscience and Mental Health, Melbourne, measured fibre density and cross-sectional area using a novel form of MRI imaging developed at the institute.

Participants, who were all enrolled in the CANVAS study, had a mean age of 69 years, 32% were women, stroke severity was generally mild and for most people (86%), it was their first stroke.

Fibre density and fibre cross-sectional area were lower in the participants with stroke than in the controls, when measured three months post-stroke using the MRI ‘fixel’ technique, designed specifically to measure white matter fibre tracts.