被殼出血の像を示した末梢性中大脳動脈瘤の1例—診断上のpitfall

A Case of Aneurysm of the Peripheral Middle Cerebral Artery Presenting Putaminal Hemorrhage : Pitfall in Diagnosis

　CTにて高血圧性被殼出血の像を呈しCT定位的血腫吸引術施行後，脳血管撮影にて左中大脳動脈末梢部に動脈瘤が認められた症例を報告する。症例は高血圧症の既往のある41歳の右利きの女性。突然の頭痛と右不全片麻痺にて発症し，CTにて左被殼出血がみられた。意識は嗜眠で右不全片麻痺を伴っていたため，翌目CT定位的血腫吸引術施行。意識は清明となるも運動性失語症と右上肢の軽度麻痺がみられた。術後14日目の脳血管撮影にて左中大脳動脈M₂部位に動脈瘤があり，左前頭側開頭にてneck clipping術施行。動脈瘤は一部血栓化しbroad neckでclippingにてparent arteryに狭窄が生じたためparent artery末梢部と浅側頭動脈との吻合術を加えた。術後，軽度の運動性失語症を残し独歩退院した。画像上，典型的な高血圧性被殼出血と考えられる症例でも末梢性中大脳動脈破裂の可能性を念頭に置き診断治療を進める必要がある。

A case mimicing hypertensive putaminal hemor rhage which was first treated by CT-guided stereo-tactic aspiration and eventually diagnosed as a sequence of the ruptured aneurysm of the left peripheral middle cerebral aretry on postoperative angiography is presented. This 41 old, right-handed, hypertensive female suffered sudden onset of head-ache and right hemiparesis. Next day hematoma was evacuated by the CT-guided stereotactic aspi-ration because of progressive deterioration of the consciousness and patient recovered well. Fourteen days after the evacuation when she presented mild right hand weakness and motor aphasia, angoigra-phy revealed a saccular aneurysm with broad neck derived from left posterior parietal artery. A neck clipping necessitated an additional anastomosis between superficial temporal artery and distal mid-dle cerebral artery because of parent artery stenosis. Postoperatively she is doing well with slight motor aphasia.

Among the typical hypertensive putaminal hemor-rhage diagnosed on CT scan, it is stressed that there may be a possibility of ruptured aneurysm situated on the peripheral middle cerebral artery.