Focal dural arteriovenous fistula (DAVF) presenting with progressive cognitive impairment including amnesia and alexia.

A 75-year-old woman with a dural arteriovenous fistula (DAVF) presented with progressive cognitive impairment including amnesia and alexia. Neuroradiological studies showed a relatively confined DAVF lesion in the left temporal lobe. The patient did not have a history of trauma and did not complain of headache or tinnitus. Amnesia and alexia dramatically improved upon treatment of the DAVF, and this was associated with attenuation of an abnormal MRI signal in the left temporal lobe. The results suggest that gradually impaired cerebral circulation due to focal venous hypertensive encephalopathy localized to the left temporal lobe and resulting from a DAVF could be involved in slowly progressive amnesia and alexia. The case also shows that an intracranial DAVF may present as a variety of neurological symptoms, depending on its localization, size and clinical stage.