[Two cases of ischemic cerebrovascular disease with only memory disturbance as neurological symptom and abnormal MR findings].

Case 1 involved a 77-year-old man admitted to our hospital after he lost almost all memory of work on the day before. Diffusion-weighted imaging (DWI) revealed spotty hyperintensities in the bilateral hippocampi, which were considered responsible for the amnesia. Transesophageal echocardiography (TEE) showed severe aortic arch atheroma, 6.8 mm in diameter with extension to the branch. Aortogenic embolism to the bilateral hippocampi was diagnosed. Case 2 involved a 66-year-old woman admitted to our hospital because she had lost all memory of the 5 hours she was out. She had transient anterograde amnesia. DWI revealed no ischemic lesions, but magnetic resonance angiography (MRA) revealed branch occlusion of the right posterior cerebral artery. MRA on hospital day 7 revealed partial recanalization. TEE showed aortic arch atheroma of 3.9 mm in diameter with extension to the branch. In both cases, aortogenic embolism to the hippocampus might have been causally related to transient memory disturbance. In patients with acute memory disturbance, the possibility of ischemic stroke should be considered.