Endovascular Treatment of 300 Consecutive Middle Cerebral Artery Aneurysms: Clinical and Radiologic Outcomes

BACKGROUND AND PURPOSE:There is controversy as to the best mode of treating MCA aneurysms. We report the results of a large endovascular series of patients treated at our center.MATERIALS AND METHODS:This study was a retrospective analysis of a prospectively acquired data base. All patients with saccular MCA aneurysms treated between November 1996 and June 2012 were included. World Federation of Neurosurgical Societies grade, aneurysm site, size, and aneurysm neck size were recorded, along with clinical outcome assessed with the Glasgow Outcome Scale and radiographic occlusion assessed with the Raymond classification at 6 months and 2.5 years.RESULTS:A total of 295 patients with 300 MCA aneurysms were treated including 244 ruptured aneurysms (80.7%). The technical failure rate was 4.3% (13 patients). Complete occlusion or neck remnant was achieved in 264 (91.4%). Complications included rupture in 15 patients (5%), thromboembolism in 17 patients (5.7%), and early rebleeding in 3 patients (1%). Overall permanent procedural-related morbidity and mortality were seen in 12 patients (7.8%). Of the ruptured aneurysms, 189 (79.4%) had a favorable clinical outcome (Glasgow Outcome Scale score, 4–5). A total of 33 patients (13.6%) died. On initial angiographic follow-up, aneurysm remnant was seen in 18 aneurysms (8.1%). A total of 13 patients (4.3%) were re-treated.CONCLUSIONS:Our experience demonstrates that endovascular treatment of MCA aneurysms has an acceptable safety profile with low rates of technical failure and re-treatment. Therefore, coiling is acceptable as the primary treatment of MCA aneurysms.

The International Subarachnoid Aneurysm Trial (ISAT) demonstrated an absolute 6.9% reduction in the rate of death or dependency at 1 year for patients treated with endovascular coiling (EVC).¹ ISAT did not, however, address the specific issue of patients with MCA aneurysms, who represented only 303 (14.1%) of the 2143 enrolled patients. This has resulted in controversy as to the best mode of treatment of aneurysms at this location. Surgical clipping remains the standard treatment in many institutions. The anatomic location aids surgical access, and in some cases, surgery facilitates hematoma evacuation. There is also a perceived increased risk for EVC at this site because these aneurysms are often wide-neck and have branches arising from the neck.^2,3 Recently, several surgical series have been published that demonstrate excellent clinical results with low rates of morbidity and mortality.^4–7 Therefore, we analyzed the strategy at our institution where EVC is the first-line therapy for aneurysm treatment at any location and focused on the more controversial MCA aneurysms.