Microsurgical Findings of Pial Arterial Feeders in Intracranial Dural Arteriovenous Fistulae: A Case Series

BACKGROUND Pial arterial feeders in an intracranial dural arteriovenous fistula (dAVF) are risk factors for both ischemic and hemorrhagic complications during endovascular embolization. Microsurgery in dAVF with pial arterial feeders has rarely been reported. OBJECTIVE To assess our original experience with microsurgery for dAVF with pial arterial feeders by investigating surgical findings and outcomes. METHODS In 40 patients with intracranial dAVF who underwent microsurgery, we found 8 patients who had pial arterial feeders. A retrospective review was conducted. RESULTS The locations of the dAVFs were as follows: tentorium, 2 patients; Galenic system, 1; straight sinus, 1; torcula, 1; transverse sinus, 1; ethmoid, 1; and convexity, 1. Preoperative angiography revealed that the pial arterial feeders originated from the middle cerebral artery in 2 patients, the anterior cerebral artery in 1, the posterior cerebral artery in 2, and the posterior medial choroidal artery in 1. Of note, in 2 patients (6.7%), feeders from the superior cerebellar artery were determined to be angiographically occult during preoperative examination and were detected through careful intraoperative observation and arachnoid dissection. In 5 cases, the additional obliteration of the pial arterial feeders and/or more distal cortical venous drainers after the simple disconnection of proximal cortical drainers was necessary to cure the dAVF. Finally, all shunts were cured with only 1 minor complication. CONCLUSION Although microsurgical results were acceptable, the surgeon should be aware of the presence of pial arterial feeders even after the simple disconnection of cortical venous drainage. Angiographically occult feeders may also exist.