Embolectomy Through Aneurysm Wall for Iatrogenic Occlusion of M1 Portion During Coil Embolization: Technical Note for Transaneurysmal Embolectomy.

Objective: We describe the technique for surgical "transaneurysmal" embolectomy in a patient with subarachnoid hemorrhage and multiple cerebral aneurysms who manifested large-vessel occlusion during coil embolization.

Methods: An 84-year-old woman with subarachnoid hemorrhage and bilateral internal carotid artery (ICA)-posterior communicating artery and bilateral middle cerebral artery aneurysms (MCAs) was admitted to our institution. We performed clipping to the left ICA and MCAs; however, we could not find the rupture point of both aneurysms. We chose to treat 2 aneurysms on the other side by coil embolization. After complete coil embolization of a right ICA aneurysm, angiograms showed occlusion of the right MCA just proximal to an MCA aneurysm. Considering the risk of bleeding of an untreated MCA distal to the occlusion by endovascular thrombectomy, we performed open transaneurysmal embolectomy at the occlusion site and surgical clipping of the MCA. After cutting the aneurysmal wall, we inserted a suction tube into the cut surface of the aneurysm. The clot was gradually and completely pulled through the cut surface of the aneurysm. Finally, the aneurysm was completely clipped with titanium clips to preserve the M1 and M2 branches.

Conclusions: Different from usual surgical thrombectomy, suturing the vessel wall is not required for transaneurysmal embolectomy and the area of brain ischemia is confined. Aneurysms with the fragile wall may rupture during clearance of tissue on the aneurysmal surface, and suction may increase vessel damage. Conclusions: Transaneurysmal thrombectomy may be useful and safe for large-vessel occlusion just distal to cerebral aneurysms.