Proof-of-Principle for AVM Embolization Complications Caused by the Proximal Occlusion Technique Using Onyx: A Theoretical Basis for Ante-Grade Drifting Technique

To analyze the complications of the standard proximal plug technique in arteriovenous malformations (AVMs) embolization by Onyx and promote ante-grade drifting technique for AVM embolization. Seven publications reporting complications of AVM embolization by Onyx were identified and reviewed. Render descriptive statistics regarding causes of ischemic and hemorrhagic complications within 1 month following treatment were provided. A novel Onyx injection technique was proposed to overcome these problems. All reported transarterial Onyx AVM embolizations were conducted by employing the proximal plug technique. Causes of complications elicited by utilizing this strategy may generally be attributed to long-fluoroscopy and long-procedure times, embolisate reflux across a considerable extent of the vessel, catheter entrapment, extravasation of Onyx from the arterial lumen, catheter transgression through the arterial wall, the use of an Onyx volume exceeding, and venous occlusion preceding arterial feeder shutdown. Complications occurring during the course of attempts at embolizing AVMs utilizing Onyx constitute unfortunate causes of patient morbidity resulting from this conventional technique. We suggest that institution of a novel "ante-grade drifting technique" for Onyx injection may avoid these commonly elicited deficits. The proximal plug technique has a series of drawbacks that lead to serious adverse outcomes of AVM embolization. The Onyx embolization technology for AVM could be updated to improve clinical outcomes.