Teaching NeuroImages: MRI-visible Virchow-Robin perivascular spaces in cerebral small-vessel disease.

MRI-visible perivascular spaces (PVS) in centrum semiovale white matter (CS) have been proposed as a novel neuroimaging marker for cerebral amyloid angiopathy (CAA). Progressive b-amyloid deposition in small cortical and leptomeningeal arteries in CAA may gradually impair perivascular drainage and cause retrograde PVS dilation. We describe the neuroimaging findings of 2 patients who were diagnosed with small-vessel pathologies: probable CAA (case 1, figure, C and D) and probable CAA and hypertensive arteriopathy (case 2, figure, A and B). Susceptibility-weighted brain MRI showed extensive cortical and infratentorial microbleeds (figure, A and C, I/II, respectively) and severe PVS enlargement in basal ganglia (figure, B) and CS (figure, D). MRI-visible PVS may identify patients at risk of developing CAA.