嚢胞性髄膜腫腫

THE CYSTIC MENINGIOMAS

はじめに

　髄膜腫が，まれに嚢胞を形成することは，成書にも記載され周知のことであるが，実際にこのような嚢胞性髄膜腫に遭遇することはきわめてまれで，その報告も少ない。われわれの教室で1970年6月末まで経験した420例の髄膜腫のうちで，かかる嚢胞を形成したものは，わずか5例にすぎない。そこで，これらの症例を報告し，あわせて病理組織学的および臨床的にその病理発生について，種々の考察を加えてみたいと思う。

The authors reported five cases of the cystic men-ingioma. The first case was 36 years old female, whose complaints were attacks of generalized con-vulsion, headache and dimness of vision. At the operation, a goose-egg sized tumor attached to the falx was removed and the tumor was found to contain a large cyst within.

The scond case was 41 years old male, who had spells of hemiconvulsion and hemiparesis on the right side with hypesthesia of the arm on the same side. At the operation, a tumor in the left frontal parasa-gittal area accompanied by multiple cysts was as-certained.

The third case was 23 years old male, who de-veloped headache, blurred vision and episodes of generalized convulsions. At the operations, a large cyst beneath the cerebral cortex was encountered in the left temporal lobe. The cyst was covered with the bloody dark red tumor which invaded diffusely into the surrounding brain.

The fourth case was 22 years old female, who developed auditory impairment on the right side, bilateral tinnitus, headache and staggering gait. At the operation, a pigeon-egg sized cystic tumor was found at the right cerebellopontine angle.

The fifth case was 49 years old female, whose chief complaints were the occasional attacks of hea-dache with nausea and the slight hemiparesis on the left side. At the operation, a cyst was dis-covered in the right frontal parasagittal area and the tumor was present as a mural nodule on the wall.

The reports of the pathological examination were all meningiomas of fibroblastic type except for men-ingothelial type of the fourth case and myxomatous or hydrotropic degeneration was notorious in all cases. As the pathogenesis of such degeneration, the vascular insufficiency caused by the hyaliniza-tion of wallsof vessels was suggestive.

By the review of 420 cases of meningiomas ever experienced in the clinic, the authors made consider-ations on the pathogenesis of the macroscopic cyst formation which may be intimately correlated with the microscopic myxomatous degeneration.

The conclusion was as follows ; age, sex, location of the tumor, pathological type of the tumor, head injury or convulsive seizure was not considered as the sole cause of the cyst formation.