Abstract
Dural arteriovenous fistulas (DAVFs) are generally present in the transverse-sigmoid sinus as well as the cavernous sinus. To date, endovascular surgery has been mainstream; however, direct surgical treatment seems to be primarily limited to anterior skull base DAVFs. We herein report two cases of non-sinus-type DAVF located in the middle cranial fossa that were successfully treated with direct surgery. Both were symptomatic and angiographically classified as Cognard type IV. The first case was referred to our institution because of recurrence of a left middle fossa DAVF seven years after initial treatment with transarterial coil embolization (TAE). Drainer obliteration was performed using the subtemporal approach. The second case had severe headache with prominent clinical features similar to those of a carotid cavernous sinus fistula. TAE was applied to the branches of the right external carotid artery to reduce the flow rate. Drainer obliteration was performed without difficulty using the conventional frontotemporal approach.
The cortical vein-draining DAVF, classified as Cognard type III or type IV, presents a high risk of intracranial hemorrhage. When diagnosed, they should be treated completely, as early as possible. The aforementioned drainer obliteration appeared to be the best way to cure the DAVF. Endovascular surgery before direct surgical treatment was effective to reduce shunt flow and to enable an easy access to the shunt point.
