非外傷性天幕下硬膜下水腫の1手術治験例

A CASE OF NON-TRAUMATIC SUBTENTORIAL SUBDURAL HYGROMA

はじめに

　慢性硬膜下血腫の一特殊型として1894年，Mayo^1）により初あて記載された硬膜下水腫は，その成因の多くは頭部外傷に起因するといわれているが，その頻度は同じく頭部外傷に基づく外傷性硬膜下血腫よりもさらに稀なものとされている。

　本症の発生部位としては，その成因が外傷性，非外傷性を問わず天幕上が大部分を占め天幕下に発生せる報告例は，著者らの調べえた範囲では，城後^2）の1例，平井^3）の6例，Fischer^4）の7例，合計14例のみで，いずれも頭部外傷に起因する症例である。

Because of it's rarity, the authors had reported a case of non-traumatic subtentorial subdural hy-groma.

The patient was 23-year-old male without the history of head trauma and his present complaints had started two months prior to admission with the symptoms of increased intracranial pressure which was measured as high as 230 mm H2O in lying position.

After the regulation of the intracranial pressure was obtained following V-A shunt, the patient showed apparent improvement in general condition. However, mild cerebeller signs had become promi-nant suggesting cerebeller lesion. Brachial angio-graphy was done and it revealed thin avascular area between cerebeller surface and suboccipital skull with hypervascularity in subtentorial area in lateral view.

Subtentorial craniectomy done on 5-10-'65 with suspicion of cerebeller tumor revealed huge sub-duralhygroma containing fluid with amount of 30 cc. Several exploratory punctures was performed through bilateral cerebeller hemispheres and no tumor was found.

He had good convalescence post-operatively and discharged on 8-3-'69 with free of any neurologi-cal signs and symptoms.

The pathogenesis, incidence, symptoms and signs, and method of surgical treatment were discussed about the subdural hygroma and stressed rare inci-dence of subtentorial subdural hygroma due to non-traumatic origin.