ステント併用コイル塞栓術を施行した椎骨動脈紡錘状動脈瘤の1例―ステント内へのコイル逸脱防止の工夫―

A Case of a Vertebral Artery Fusiform Aneurysm Treated with Stent Assisted Coil Embolization: Technique to Prevent Coil Migration

Ⅰ．は じ め に

　近年，頸部が広い脳動脈瘤に対してステントを併用したコイル塞栓術が行われるようになった^1,3)．椎骨動脈紡錘状動脈瘤に対してもステント併用コイル塞栓術では血流を温存でき，対側椎骨動脈低形成の症例などに適応となる．紡錘状動脈瘤に対してはステント周囲を全周性に塞栓することになり，その塞栓方法は通常の動脈瘤塞栓術と異なる．本稿では症例を提示し，ステント留置，マイクロカテーテルの誘導，コイルの選択，内腔側へのコイル逸脱の防止などに関して検討する．

　Placement of a stent over the aneurysm neck and secondary coil embolization prevents coil migration and allows attenuated packing of the coils. However,during the course of the embolization,coils project over and obscure the parent vessel. Here we report a novel technique for endovascular parent vessel reconstruction with aneurysm embolization. A 73-year-old male had an incidental fusiform aneurysm at the V4 segment of the left vertebral artery. The size of the aneurysm increased from 7 mm to 8 mm in diameter. Since the right vertebral artery was hypoplastic,endovascular parent vessel reconstruction with coil embolization was performed. A flexible balloon-expandable coronary stent was navigated to the lesion and deployed successfully followed by coil embolization using a microcatheter through the stent. The balloon was inflated intermittently during coil insertion avoiding coil migration to inside the stent. Furthermore,the angle of the image intensifier was manipulated to visualize the inside of the stent. Postoperative course was uneventful and follow-up MRI three moths later demonstrated obliteration of the aneurysm and patency of the parent artery. This technique provides a practical treatment strategy for the management of a circumferential aneurysm.