後頭蓋窩メニンジオーマ

MENINGIOMA IN THE POSTERIOR CRANIAL FOSSA

序言

　メニンジォーマ（meningioma）という言葉は1922年Cushing^1）により始めて与えられたもので，頭蓋内に比較的屡々みられる発育の遅い良性の腫瘍であり，arachnoidから発生すると考えられている。本疾患は発育が遅いので，天幕上のみならず，天幕下でも周囲の臓器即ち後頭蓋窩では，小脳や脳幹部が之に適応して腫瘍が比較的大きくなるまで放置されていることが多く，周囲の臓器との関係で全剔出が困難になり易い。最近本疾患の手術死亡率が低下して来ているようであるが，之はMarkharn^2）等が指摘しているように，最近の抗生物質の急速な発達や，麻酔特に低体温法の応用等も関与しているが，更に大きな要素は早期診断がなされるようになつたからであつて，手術が早ければ早い程死亡率が減り，予後も良いということであろう。ここに吾々の教室が経験した後頭蓋窩meningioma15例を中心として，文献的考察を加え概要を述べたいと思う。

At Kyoto University's Surgical Department, First Division, 15 cases of meningiomas in the posterior cranial fossa were brought up for discussion, with a study of the reports con-cerning meningioma. It was found that :

1) Out of 897 of all brain tumors handled, 125 were found to be meningiomas,but only 15 of them (12%) were found in the posterior cranial fossa.

2) The age of patients was between 15 and 58,(38 was average).

3) More cases were found among females than males : the sex ratio was 2 : 3.

4) As reported in most cases,the favoura-ble site of this tumor was at the cerehello-pontine angle, the tentorium, and then at the cerebellar convexity.

5) The periods between onset and operation were generally long (3 years in average).

6) The clinical pictures were mostly re-presented by increased intracranial pressure ; cerebellar or cerebral nerve symptoms were associated with many cases.

7) General diagnostic measures were dis-cussed, and special emphasis was placed on the necessity of angiography (especially ver-tebral angiography) and iodized oil ventricu-lography.