Balloon-assist technique for endovascular coil embolization of geometrically difficult intracranial aneurysms

OBJECTIVE: The balloon-assist or neck-remodeling technique is an adjunctive method devised for the endovascular coil embolization of aneurysms charact erized by a wide neck or unfavorable geometric features. Since its initial description, there have been few data to corroborate its utility, efficacy, and safety in aneurysm embolization. METHODS: Twenty patients (19 female patients and 1 male patient) with 22 an eurysms (19 unruptured aneurysms and 3 ruptured aneurysms) underwent balloo n-assisted coil embolization. The balloon-assist technique was performed in the same treatment session after conventional coil embolization had failed in 55% of cases (12 of 22 cases) and was the primary treatment in 45% of c ases. The majority of aneurysms were located in the supraclinoid carotid ar tery (13 paraophthalmic and 3 superior hypophyseal aneurysms). The mean ang iographic measurements included a fundus of 8.7 +/- 3.7 mm, a neck of 5.3 /- 2.2 mm, and a comparatively unfavorable fundus/neck ratio of 1.33 +/- 0. 23. RESULTS: Technical success was achieved in 77% of cases (17 of 22). The rat e of aneurysm obliteration at the end of the procedures was 97 +/- 3.8%. An giographic follow-up data (mean follow-up period, 10.3 mo) obtained for 89% of the treated aneurysms (15 of 17) confirmed stable mean occlusion of 97. 8 +/- 3.8%. Technical complications included two cases of asymptomatic dist al vessel thromboembolism, which resolved angiographically within 24 hours, and one case of intraprocedural rupture of an arteriovenous malformation-r elated feeder artery aneurysm, which resulted in no neurological deficits a nd required no further treatment (transient complication rate, 13.6%; 3 of 22 cases). There were no deaths and no procedure-related 30-day or permanen t morbidity. CONCLUSION: The balloon-assist method of coil embolization is characterized by promising intermediate-term angiographic and clinical outcomes and acce ptable morbidity and mortality rates. Although this adjunctive method requi res the use of an additional microcatheter and consequently involves a high er level of technical complexity, it extends the range of aneurysms that ca n be successfully treated with electrolytically detachable coils via an end ovascular approach.