[A case of dural arteriovenous fistula associated with bilateral thalamic lesions]

We report a 51-year-old man with a dural arteriovenous fistula (DAVF) associated with bilateral thalamic lesions. He was admitted to our hospital because of cognitive disorder. T2-weighted MRI and fluid-attenuated inversion recovery (FLAIR) sequence of the brain revealed symmetric hyperintense lesions of bilateral thalamus and abnormal flow void that represents the enlarged veins. Cerebral angiography demonstrated DAVF in the superior petrosal sinus (SPS). It was mainly supplied by the internal carotid arteries. The strait sinus was not revealed, and the venous drainage was retrograde into the internal cerebral vein. Therefore the mechanism of cognitive disorder in this case was considered to be vasogenic edema of the bilateral thalamus due to DAVF of SPS. We decided to treat the DAVF by embolization via the feeding arteries approach, because strait sinus was not revealed and venous approach was difficult. After embolization, the size of DAVF was remarkably reduced. His cognitive disorder was markedly improved and the hyperintense area on T2-weighted MRI and FLAIR sequence had disappeared. Cognitive disorder due to DAVF of SPS is very rare. It is also difficult to diagnose bilateral thalamic lesions as DAVF, but it may be reversible by DAVF treatment. Thus, early diagnosis and treatment is important. Like this case, abnormal flow void that represents the enlarged veins could help to diagnose bilateral thalamic lesions due to DAVF.