Transcirculation Approach for Endovascular Embolization of Intracranial Aneurysms, Arteriovenous Malformations and Dural Fistulas: A Multicenter Study

Abstract Background Unfavorable anatomy can preclude traditional anterograde endovascular interventions. Transcirculation approaches, which consists of primary catheterization of a target artery from the contralateral side or opposite cerebral circulation, can provide alternative pathways for successful treatment of these cases. We aimed to assess the safety, efficacy and outcomes of endovascular embolization through transcirculation approaches. Methods Nine centers provided retrospective data on patients whom underwent transcirculation procedures for embolization of intracranial aneurysms (IAs), dural arteriovenous fistulas (dAVFs) and arteriovenous malformations (AVMs). Raymond-Roy Occlusion Classification grades (RROC) and degree of obliteration were used to evaluate treatment success. Minor/major complications and clinical/angiographic outcomes were also assessed. A review of the literature reporting on patients whom underwent transcirculation embolizations was also performed. Results Forty patients were included in the study = 34 IAs, 3 AVMs and 3 dAVFs. Most IAs (22/34, 64.7%) were treated electively. Three AVMs and 2 dAVFs presented ruptured. RROC I–II was achieved in 97% of IAs. All AVMs and dAVFs were completely obliterated. One patient developed a transient arterial thrombus that was successfully treated with intravenous tirofiban. The most common indications for a transcirculation approach were: difficult access angle of the target lesion (42.5%) and occlusion of the parent artery (27.5%). The review of the literature pooled a total of 152 IAs treated via transcirculation approaches. Most common locations were basilar tip (27%), posterior inferior cerebellar artery (25%), and internal carotid artery (15.1%). PCOM was crossed in 60 (39.5%), ACOM in 48 (31.6%) and VA in 37 (24.3%) cases. Primary coiling alone was performed in 22 (14.5%), stent-assisted (SAC) in 67 (44.1%), balloon-assisted (BAC) in 36 (23.7%), SAC + BAC in 20 (13.2%) and flow-diversion in 7 (4.6%) cases. After intervention, 142 (93.4%) IAs achieved successful RROC grades I-II. Two (1.3%) major complication leading to death were reported, both intra-procedural aneurysmal ruptures with massive subarachnoid hemorrhage and herniation. After a mean angiographic follow-up of 11.3 months, only 6/108 (5.6%) IAs showed intrasaccular filling/recurrence. Conclusions Transcirculation approaches appear to the safe and effective in the treatment of IAs, dAVFs and AVMs. The most common indication for a transcirculation approach is the presence of a difficult angle to access the target lesion and occlusion of the parent artery.