後腹膜出血で発症し，経動脈的および経静脈的塞栓術により根治に至ったparaspinal arteriovenous fistulaの1例

A Case of a Paraspinal Arteriovenous Fistula Presenting with Retroperitoneal Hemorrhage Treated by Staged Transarterial and Transvenous Embolization

Ⅰ．はじめに

　Paraspinal arteriovenous fistula（AVF）は非常に稀な疾患であり，硬膜内脊髄血管奇形や脊髄硬膜動静脈瘻とは異なり，動静脈シャントの部位は椎体周囲の軟部組織や筋組織，椎間孔，椎体内などの硬膜外に存在する．症状は血管性雑音のみを示すものから，硬膜内への逆流による静脈還流障害や脊髄・神経根の圧迫症状，さらには出血を呈するものまでさまざまである^2,6-10,12)．今回われわれは，交通外傷後に後腹膜出血で発症し，経動脈的および経静脈的塞栓術を施行したparaspinal AVFの1例を経験したので，文献的考察を含めて報告する．

　We report a rare case of a paraspinal arteriovenous fistula（AVF）treated by combined transarterial and transvenous embolization（TAE/TVE). A 72-year-old woman was admitted after a traffic accident.

　Abdominal enhanced CT disclosed pre-existing large varices at the L3-L4 level in the right retroperitoneum with multiple feeding arteries and veins draining into the extradural venous plexus in the spinal canal. The lesion was diagnosed as a paraspinal AVF. Four days later, the patient went into a state of shock.

　Emergency abdominal CT showed retroperitoneal hemorrhage due to rupture of the varix. TAE of the feeders from the right L1-L4 arteries was performed, and rebleeding from the varix was prevented. Three months later, follow-up CTA showed regrowth of the AVF, and TVE was performed. Two microcatheters were navigated transvenously into the varix, and detachable coils were delivered into the small compartment just downstream to the shunts, leading to complete obliteration. We conclude that transarterial flow reduction followed by occlusion of the venous side of the shunts is effective to achieve cure of a complex and high-flow paraspinal AVF.