解離性椎骨動脈瘤の破裂により動静脈瘻を来たした神経線維腫症の1例

A Case of Neurofibromatosis Type 1 Associated with Arteriovenous Fistula Caused by Re-bleeding of a Vertebral Dissecting Aneurysm

I．はじめに

　神経線維腫症1型（neurofibromatosis type 1）は第17染色体に異常のある常染色体優性遺伝性疾患であり，neurofibromaやcafé-au-lait spotなど主に外胚葉系の異常のほか，血管病変など中胚葉系の異常も合併することが知られている^4,11）．脳血管病変では閉塞性変化が大部分であるが動脈瘤や動静脈奇形（瘻）の報告も散見される．今回われわれは，くも膜下出血を来たした神経線維腫症の患者において解離性椎骨動脈瘤を認め，血管内手術中に動脈瘤の破裂により動静脈瘻となった症例を経験したので文献的考察を加え報告する．

We described a dissecting aneurysm of the vertebral artery (VA), which was associated with neurofibro-matosis type 1 (NF1). A 41-year-old man was referred to our hospital because of abrupt, severe headache.A CT scan revealed diffuse subarachnoid hemorrhage (SAH) predominantly in the prepontine cistern. Theangiograms showed a string sign in the left VA, just distal to the posterior inferior cerebellar artery(PICA). The vertebral dissection was considered responsible for SAH, and endovascular occlusion of theleft VA was attempted. During the intervention, the patient complained of severe neck pain at the time ofselective vertebral angiography, which revealed an arteriovenous fistula. The VA was occluded proximalto the PICA with GDC, which covered the fistula. Open surgery confirmed the two unruptured aneurysms. Intracranial dissection is rarely reported in association with NF1. However, ateriovenous fistula is not anuncommon combination with dissecting aneurysm and the extracranial segment of the VA is a characteris-tic target. Anatomical feasibility is conceivably the pathogenesis.