Persistent primitive trigeminal arteryに合併した脳動脈瘤の新生

De Novo Aneurysm Associated with a Persistent Primitive Trigeminal Artery:Case report

I．はじめに

　Persistent trigeminal artery（以下PTA）は遺残血管の中でも最も頻度が高く，脳動脈瘤や脳動静脈奇形の合併が報告されている．脳動脈瘤の新生を早期に認識することは，クモ膜下出血を扱う脳神経外科医にとって，一つの理想である．しかし，脳動脈瘤がいつ新生されるかは不明であり，現在までPTAを追跡し，脳動脈瘤の新生を確認したという報告はない．著者らは6年前の脳血管撮影でPTAを指摘され，今回新たに未破裂脳動脈瘤を見いだし，クリッピングを行った症例を報告する．

This paper presents a case of a de novo unruptured anterior communicating aneurysm associated with a persistent primitive trigeminal artery. The patient was a 65-year-old female with tinitis, for whom computed tomography with contrast medium indicated right dural enhancement. Dural arteriovernous malformation was suspected and angiography was thus conducted. A right persistent primitive trigeminal artery was demon-strated but no aneurysm could be found. Six years later, magnetic resonance angiography indicated an aneurysm on the anterior communicating artery. It was subse-quently removed by surgery. A persistent primitive artery is frequently found to accompany aneurysm but de novo aneurysm associated with such an artery does not appear in the literature to date. The authors empha-size the importance of follow-up angiography in cases of persistent primitive artery not accompanied by an aneurysm.