Objective: Because of their anatomic configuration, middle cerebral artery (MCA) aneurysms are most often treated with surgical clipping. However, endovascular coil embolization of these aneurysms is an increasingly used alternative. We retrospectively reviewed the anatomic and clinical outcomes of patients with MCA aneurysms who underwent endovascular treatment at our institution.
Methods: One hundred fifteen MCA aneurysms in 115 patients (mean age, 55.1 years) were treated by an endovascular technique from April 1990 to March 2007. Forty-eight patients (42%) presented with acute subarachnoid hemorrhage, and 67 patients (58%) had unruptured aneurysms. Fifty-three aneurysms (46%) were small with a small neck, 28 (24%) were small with a wide neck, 22 (19%) were large, and 12 (11%) were giant.
Results: Angiographic results immediately after embolization showed complete occlusion in 53 aneurysms (46%), a neck remnant in 51 (44%), and incomplete occlusion in 3 (3%). Because of anatomic difficulties, we could not embolize 8 aneurysms (7%). Thirteen patients underwent combined treatment that included endovascular and extracranial-intracranial bypass surgery. Morbidity and mortality rates were 6.9% (8 patients) and 3% (3 patients), respectively. Procedure-related complications were encountered in 10 patients (9%). Seventy patients had long-term follow- up angiograms. Seven aneurysms (10%) were recanalized; all were large or giant. One partially embolized large aneurysm ruptured 13 months after embolization.
Conclusion: In this series, endovascular coil embolization of MCA aneurysms has morbidity and mortality rates comparable to those of conventional surgical clipping. Combined treatment of endovascular and bypass surgery can successfully treat large or giant complex fusiform MCA aneurysms.