Guglielmi Detachable Coil Embolization of Posterior Circulation Aneurysms: A Systematic Review of the Literature

Background— Early multicenter trials of Guglielmi detachable coil embolization of posterior circulations aneurysms have been followed by the publication of numerous single-center experiences. Summary of Review— We performed a MEDLINE literature search and extracted data from single-center reports containing at least 10 posterior circulation aneurysms. Twelve reports (495 aneurysms) were specific to the posterior circulation. Eighty-two percent of aneurysms arose near the basilar apex. Eighty-one percent of patients harbored unruptured aneurysms or presented in good clinical condition. Sixty-three percent of lesions were small, and 41% exhibited a narrow neck. Coil deposition was achieved in 97.6% of cases. Procedural complication and morbidity rates were 12.5% and 5.1%, respectively. Procedural and 30-day mortality rates were 1.4% and 6.7%, respectively. Complete aneurysm occlusion was achieved in 47.6%, near-complete occlusion (90% to 99%) in 43.4%, and incomplete occlusion in 9.0% of cases. There were a total of 52 recurrences (22.2%) in a subset of 234 evaluable patients. Ninety-two percent of these aneurysms exhibited wide necks. The annual risk of subarachnoid hemorrhage after embolization was 0.8%. Eighty-five percent of patients achieved functional independence, while only 5.3% lived dependent lifestyles. The overall mortality rate was 9.8%. Conclusions— The published literature approximates a large series of basilar apex aneurysms. Embolization is moderately effective in completely excluding an aneurysm from the posterior circulation. The incidence of recurrence in wide-neck aneurysms and incompletely coiled aneurysms is substantial. Coil embolization is effective in preventing early rebleeding. Its role in the treatment of unruptured aneurysms remains unclear.