Brain HealthArterial Widening Not Narrowing Drives Small-Vessel Brain Disease
A prospective study of 229 mild stroke patients found that large-artery stenosis was not associated with cerebral small-vessel disease or lacunar stroke. Instead, basilar artery dolichoectasia — abnormal widening and tortuosity — was strongly linked to lacunar stroke, higher small-vessel disease burden, incident infarcts, and white matter deterioration over one year. Wider intracranial arteries showed similar patterns. These findings challenge the long-held assumption that atherosclerotic narrowing drives small-vessel brain disease, pointing instead toward an intrinsic microvascular pathology called segmental arteriolar disorganization as the primary culprit. The results call for mechanism-specific diagnostic and treatment strategies rather than a one-size-fits-all atherosclerosis-focused approach.