Treatment of a Large Type II Endoleak via Extraperitoneal Dissection and Embolization of a Collateral Vessel Using Ethylene Vinyl Alcohol Copolymer (Onyx)

Type II endoleak is defined as persistent blood flow and pressure within an aneurysmal sac after endovascular deployment of a stent graft from patent aortic branches. This paper describes the simultaneous deployment of an endoluminal graft, with limited extraperitoneal dissection of a collateral vessel and use of an ethylene vinyl alcohol copolymer, Onyx, to obliterate a large type II endoleak.