Flow reversal bypass surgery: a treatment option for giant serpentine and dolichoectatic aneurysms-internal maxillary artery bypass with an interposed radial artery graft followed by parent artery occlusion.

Giant serpentine and dolichoectatic aneurysms (GSDAs) are a small subgroup of intracranial aneurysms that often have poor clinical outcomes and are hardly to be treated by either conservative or endovascular management. We assessed seven patients who underwent internal maxillary artery bypass using radial artery graft interposition followed by parent artery occlusion to treat GSDAs. Intraoperative Doppler ultrasonography was used to assess the patency of the graft. CT angiogram or DSA were used postoperatively. The patients received follow-up after discharge and their neurological outcomes were measured using the Glasgow Outcome Score. Postoperative angiogram demonstrated that all the grafted conduits were patent, and the aneurysms were absent in two and collapsed or shrank in five of the patients. The rate of normal life or independent daily activities after internal maxillary artery bypass in the anterior and posterior GSDA patients was 66.7 and 75 %, respectively. One patient experienced postoperative frontal ischemia and was managed conservatively. His symptoms had completely resolved at discharge. No patient encountered perforator's occlusion in the series. During 2.6 years follow-up, six patients experienced favorable outcomes. One patient died in the third year after discharge attribute to unrelated disease. Based on the mechanism of flow reversal, internal maxillary artery bypass with radial artery graft followed by patent artery occlusion is an effective, minimally invasive treatment modality for select patients with GSDAs.