中脳水道狭窄症の1例

A CASE OF NON-TUMORAL STENOSIS OF THE AQUEDUCT OF SYLVIUS

I．はじめに

　非腫瘍性の中脳水道狭窄症についてはHilton^7）の報告がその最初と思われる。その後の報告で剖検材料によつて狭窄部の連続切片を作成し，非腫瘍性であることを確認されたものは50数例である。剖検によらずレントゲン学的にまたは手術的に腫瘍性の狭窄であると認めた例は著者の調べ得た範囲でも約110例あり，さして稀なものとはいえないが^{5）8）12）16）17）}，本邦における報告は意外に少なく，数例を数えるにすぎない。ただし経験しても報告しなかつた症例は少なくないと思われる。今日われわれがここに報告しようとする症例も組織所見を得ていないので確証はないが，その手術所見，臨床経過よりみて非腫瘍性の中脳水道狭窄症と思われる。特にこのような疾患の治療にさいして，手術中のレ線検査により狭窄部の状態を確認しておくことが重要と考えるので，若干の文献的考察を加えてここに報告する。

A case of suspicious stenosis of the aqueduct of Sylvius of a 14 year old boy was reported. He com-plained of progressive headache and vomiting over the last one year and had distinct bilateral papil-ledema but neither nystagmus nor incoordination. Cerebrospinal fluid pressure by lumbar puncture revealed 40 cmH₂O. Plain film of the skull showed the evidence of chronic increased intracranial pres-sure and air from lumbar puncture filled the suharachnoid cistern and the 4 th ventricle but failed to show over the 3 rd ventricle. Air from ventricular tapping showed extensive ventricular dilation with obstruction at the upper end of the aqueduct. Myodilventriculogram demonstrated the same obstructive lesion. As we could find in the examination only the stenosis in the upper end of the aqueduct but no signs of cerebellar or brainstem tumors, a diagnosis of non-tumoral stenosis of the aqueduct was made. The aqueduct of Sylvius was explored through suboccipital craniotomy with a small vinyl-catheter. The catheter stopped at the point 5cm from the Foramen of Magendii and passed through with moderate resistance and then Myodil from 4 th ventricle was recognized to pass into the 3rd ventricle. No catheter was left in the aqueduct. His postoperative course was uneventful and papil-ledema has disappeared 3 months after the operation. Since we have no histological findings, we cannot state whether the lesion is truly non-tumoral ste-nosis of the aqueduct or not.