難治性てんかんと誤まられた後脈絡叢動脈動静脈奇形の1根治例

A CASE OF RADICAL TREATMENT OF A-V MALFORMATION FROM POSTERIOR CHOROIDAL ARTERY

はじめに

　最近私どもは，過去10年間「てんかん」という診断名で内科的治療を加え，さらに外科的治療としてForel-H野破壊術（陣内^4）5））を付加したにもかかわらず，明らかな効果をえぬまま経過中，全身痙攣発作後左半身麻痺を起こしたので，その際行なつた椎骨動脈写で脳動静脈奇形が発見され，根治の機会をえた18歳男子の1症例を経験したので報告する。

　てんかん様発作（epileptiform fit, Jackson^15））を伴なう脳動静脈奇形は珍しいものではない。しかし，本症例は前腕焦点性痙攣発作のため，そのepileptogeniclesionを皮質運動領およびそのcaudal structure，すなわち内頸動脈の支配領域にのみ求めてきたばかりに，「てんかん」という誤つた診断を下していたものであり，治療上反省すべき症例であった。

A case of paraventricular arteriovenous malfor-mation (AVM) was reported, which had long been diagnosed focal motor epilepsy. The patient was a 18-year-old boy. At age of 8 he had the first epileptiform convulsion, concomitant with head in-jury, at left forearm. Since then he had similar focal convulsion 2-3 times a month, which some-times developed to generalized seizure. Seizures were strongly resistant to any kinds of anti-con-vulsant medication, so that he was sent to our neurosurgical department for consultation whether surgery was indicated or not. X-ray examination such as plain skull films, right carotid angiography and pneumoencephalography revealed no abnormal organic findings. On electroencephalogram sharp wave was recorded in the right central region only by Metrazol provocation.

Considering these findings, instead of direct cor-tical intervention, cryosurgical Forel-H-tomy (Jin-nai) was carried out at the right side on December 16, 1965. But this operation could not bring re-markable results. He finally suffered from left hemiplegia after seizure on December 2, 1968, and he was readmitted in our department.

A round calcification of 1 cm in diameter, which was previously not seen, was found on plain skull x-ray films. This was demonstrated by vertebral angiography to correspond to paraventricular AVM, which was fed by lateral posterior choroidal artery and drained by plexus vein. On February 25, 1969, clipping of these vessels and extirpation of the AVM were carried out. Since surgery, he has had no convulsion for this one year, although he had twitching of face muscle at the first 2 months.

In review of literatures, paraventricular AVM is rare in occurrence and also very infrequent to cause epileptiform seizures.

We, neurosurgeons, must attempt all sorts of diagnostic procedures to differentiate symptomatic epilepsy from idiopathic epilepsy by establishing the diagnosis of organic lesions, especially in so-called intractable 'epileptic' patients.