Lobar versus nonlobar hemorrhage and microbleeds

Axial SWI magnetic resonance imaging from two different patients. In panel A, there are multiple lobar hemorrhages including a left parietal lobar hematoma (arrowhead) and many lobar microbleeds (arrows), without microbleeds in the basal ganglia or brainstem (not shown), meeting criteria for probable cerebral amyloid angiopathy. In panel B, there is a left thalamic hematoma (arrowhead) with microbleeds in the basal ganglia (arrows). This pattern of nonlobar hemorrhages is not consistent with cerebral amyloid angiopathy, and instead is probably caused by hypertension.