痴呆症状で発症し治療に難渋したテント部硬膜動静脈瘻の2例  [in Japanese] Tentorial Dural Arteriovenous Fistula Presenting as Dementia : Report of 2 Cases  [in Japanese]

Unlike dural arteriovenous fistula (AVF) of the transverse sigmoid and cavernous sinuses that usually have a benign natural history, tentorial dural AVF typically present with hemorrhage or progressive neurological deficit. But relatively few reports are available on tentorial dural AVF accompanied by dementia. We report here 2 cases of dementia caused by a tentorial dural arteriovenous fistula. The first case is that of a 75-year-old male complaining of dementia and gait disturbance. CT scan showed ventricular dilatation and a high density area in the posterior fossa. Cerebral angiography revealed a dural AVF of the cerebellar tentorium with retrograde drainage into cerebral cortical veins. We performed transarterial embolization and V-P shunt several times, finally adding radiosurgery. Two years later, shunting flow remained but symptoms improved. The second case is that of a 70-year-old male who presented with dementia and right hemiparesis. CT and MRI revealed venous infarction of the left thalamus. Cerebral angiography revealed a tentorial dural AVF with retrograde leptomeningeal venous drainage. We performed TAE twice and symptoms improved. But dementia recurred and MRI revealed a new venous infarction of the right thalamus. We added TAE but symptoms did not improve. So we performed surgical treatment. Two days postoperation, however, complications developed in the form of intra right occipital lobe hemorrhage. His outcome 3 months later was moderate disability. Tentorial dural AVF should be performed completely and early because of the high risk of intracranial hemorrhage. Tentorial dural AVF has been successfully treated by endovascular occlusions and/or surgical treatment sometimes in conjunction with radiosurgery. However, in elderly patients, surgical complications may be caused by rapid changes of intracranial pressure and blood flow patterns.