Diagnosis and treatment of cerebral amyloid angiopathy.

CAA is the infiltration of leptomeningeal and penetrating cortical vessels with amyloid, sparing the subcortical regions and the systemic vasculature. It occurs with increasing frequency after the sixth decade. The major clinical manifestation of CAA is lobar intracerebral hemorrhage, which can be sporadic or hereditary. CAA has also been associated with normal aging, Alzheimer's disease, cerebral infarction, and periventricular demyelination. Biochemical studies have shown that the amyloid deposits in the brains of patients with normal aging, sporadic CAA-associated hemorrhage, hereditary cerebral hemorrhage, and Alzheimer's disease are identical. The exact mechanism by which CAA produces lobar hemorrhages and the role of CAA in the development of dementia are unclear. Biopsy of the involved cerebral cortex and leptomeninges is the only definitive way to diagnose CAA. Acute management of CAA-associated lobar hemorrhage consists of aggressive control of associated hypertension and supportive care. Surgical removal of the hemorrhage has not been shown to improve survival. Antiplatelet and anticoagulant therapy should be avoided in elderly patients with known CAA.