Microcatheter looping facilitates access to both the acutely angled parent artery and cerebral aneurysms for effective embolization.

Aneurysms with an acutely angled parent artery are difficult to access for coiling. This study aimed to investigate the safety and effectiveness of microcatheter looping for embolization of cerebral aneurysms with access difficulty. Ten patients (male:female=5:5) with cerebral aneurysms treated with the microcatheter looping technique were analyzed retrospectively. The parent artery formed an acute angle with the major artery in five aneurysms. The microcatheter was looped into a "α" loop for treatment in the anterior temporal artery aneurysm and a "U" loop in the remaining nine aneurysms. All ten aneurysms were successfully treated with the microcatheter looping technique. The microcatheter tip was successfully navigated into the aneurysm sac and remained stable throughout the embolization process. All aneurysms were occluded with total occlusion in five and near-total occlusion in five, and the parent artery remained patent in all cases. No complications occurred peri-procedurally. The Glasgow Outcome Scale was 5 in all patients before discharge. Follow-up angiography six to 12 months later revealed a good occlusion status of the aneurysms. The microcatheter looping technique is effective when the conventional embolization technique fails to treat cerebral aneurysms with difficult access especially when the parent artery forming an acute angle with the major artery exacerbates difficult access to the aneurysms.