Balloon-assisted Onyx Embolization of an Extensive Mandibular Gingival Arteriovenous Malformation: a case report

This is a rare case of mandibular arteriovenous gingival malformations with episodes of spontaneous bleeding and referred to our department for emergent interventional therapy. Onyx was chose as embolic agent due to its specific physical properties and infuse under balloon-assisted technique for good penetration of embolic particles into the nidus and feeders. We present this case and share the experience of this technique. We also describe the technical details, properties of embolic agents and review some literatures in public. Correspondence Author to: Feng-Chi Hsieh Department of Radiology, Yuan’s General Hospital, Kaohsiung, Taiwan No.162, Cheng-Gong 1st Road, Kaohsiung 802, Taiwan J Radiol Sci 2014; 39: 121-125 Onyx embolization of gingival arteriovenous malformation 122 J Radiol Sci December 2014 Vol.39 No.4 (Cook Medical, USA) at proximal left external carotid artery to introduce coaxial balloon catheter. A 6-Fr Neuron (Penumbra, USA) catheter was approached into proximal left lingual artery. A 4 x 11 mm Scepter X-tra compliant coaxial balloon catheter (Microvention, USA) was then navigated deeply into left lingual artery crossing over the aneurysm mentioned previously and inflated the balloon (Fig. 2a, arrow). Before embolic agent injection, the Onyx vials were put on a shaker (Vortex-Genie, Scientific Industries, USA) for at least 30 minutes to ensure complete shaking and mixing tantalum for radiopacity. Embolic agent of Onyx 34 (Fig. 2b, arrow) (1.5 ml per vial, 8% EVOH, Covidien, USA) was infused slowly about 0.1 ml per second under balloon-assisted technique. We stopped injecting Onyx immediately and pull back the balloon slightly while the Onyx retrograde reflux near tip of balloon catheter to avoid Onyx entrapment. The upstream aneurysm was then filled up by relatively large volume of Onyx after distal feeders and nidus closure in order to prevent large amount embolic material passing through the shunt into the internal carotid circulation. Another feeder of left inferior alveolar artery was embolized as the same way. At the end of embolization, a total 7.5 ml Onyx 34 was injected. The lateral mandibular plain image revealed Onyx embolic cast 1a