AVM手術における術中超音波の有用性

Intraoperative Ultrasonography in AVM Surgery

Ⅰ．は じ め に

　超音波は以前から脳神経外科領域で頻用されていたが⁹⁾，CTやMRIに比べ解像度が劣ることから，術前診断に使用されなくなった．しかし，最近の超音波装置の発達は目覚しく，特に血行動態や血流量も解析できるcolor Doppler imagingやpower Doppler imagingなどの画像処理技術の開発により^6,12)，頸動脈狭窄病変の診断を中心に頻繁に使用されるようになってきている．筆者らは，超音波装置の簡便性および非侵襲性に^5,7)，リアルタイムに情報を得られるという特長を考慮し，AVM（anteriovenous malformation）手術の術中使用で³⁾，その有用性について検討したので報告する．

Intraoperative ultrasonography was used for the surgical resection of arteriovenous malformations in three cases. In the first case,intraoperative ultrasonography clearly demonstrated residual micro-AVM,which had seemed to be resected completely during surgery. In the second case,diminished flow of the draining vein by clipping of the feeding artery was demonstrated by ultrasonography. In the third case,intraoperative ultrasonography revealed stasis of the flow in the varix by clipping of the feeding artery. Intraoperative ultrasonography is easy to use and less expensive compared with intraoperative digital subtraction angiography or MRI and it is also effective for identifying AVMs as well as the flow patterns of the feeding arteries or draining veins. Intraoperative ultrasonography is a useful device for AVM surgery.