脳幹部に嵌入したVarixを有する上錐体静脈洞部硬膜動静脈奇形の一例—症例報告と文献的考察

Superior Petrosal Sinus Dural Arteriovenous Malfomation with Varix Indenting Brain Stem : Report of a Case and Review of the Literature

　くも膜下出血および左小脳脚内出血にて発症した64歳男性で，左上錐体静脈洞部に主座を置くtentorial dural AVMの稀な一例を報告した。本例は，左外頸動脈の複数の硬膜枝よりfeedされ，drainerは脳幹部に嵌入したvarixを伴う脳底部皮質静脈を経て，狭窄した直静脈洞，および胎生期遺残の大脳鎌静脈洞に還流されていた。治療はまず，superselective catheterization法により，左外頸動脈よりのfeeding arteryの塞栓術を行った後，左後頭下開頭によるdrainer clippingを行い，完全なnidusの消失が得られた。症例は，新たな症状の発現も無く，発症時より存在した軽度の右片麻痺を残し退院した。Tentorial dural AVM症例でその臨床症状，feeding artery, nidusの位置，draining veinおよびその状態，治療法等の記載の明らかな報告は，本例も含め27例が検索しえた。これらを基に，その臨床症状，脳血管写所見，治療法，成因について若干の考察を加え報告した。

A rare case of the dural AVM mainly around the left petrosal sinus was reported. A 64 years old man was admitted just after the sudden onset of severe headach and nausea. The CT scan revealed subara-chnoid hemorrhage in the left ambient cisterns. A small hematoma was also found in the left cerebel-lar peduncle. External carotid angiogram showed a dural AVM which nidus was located adjacent to the left superior petrosal sinus. Its feeding arteries were as follows ; the middle meningeal artery, the artery of foramen rotundum, the accessory menin-geal artery, the dural branch of occipital artery and the ascending pharyngeal artery. The voluminous petrosal vein and the dilated cortical veins were identified as drainers and, the portion of the latter appeared as "varix" embedded in the pons, which was clearly delineated by MRI. In the venous phase, stenotic straight sinus and residual Falcine sinus were illustrated. Superselective embolization of the feeding arteries was employed followed by the direct clippings of draining vein. Postoperative course was uneventful. The present case should be classified into the tentorial dural AVM. Only 26 cases of this rarely encountered entity was reported in the literature. Based on both the present and the previously reported cases, the clinical features, treatment and pathogenesis of this disease were briefly discussed.