脳梁脂肪腫の一例

A CASE OF LIPOMA OF THE CORPUS CALLOSUM

I．はじめに

　頭蓋内に発生する脂肪腫は，Sosman, M．C．^13）の頭蓋単純写所見の報告以来，特異な石灰化像を示すことが知られている。近年，脂肪腫の血管写所見についても，他に類をみない奇型的変化を呈している報告がなされている^8,9）。

　我々は，頭蓋単純写所見で，典型的石灰化像を示し，血管写所見では，特異な血管異常を呈した脳梁脂肪腫の一例を経験したので報告し，臨床所見，レ線所見，治療および予後について文献的な考察をおこなう。

Presented here is a case of lipoma developed in the corpus callosum of a 16-year-old girl. Her chief complaints were the convulsion with a pos-sible psychomotor component and the urinary disturbance. The patient, being more or less obesity, revealed no special sign in the neurological examinations.

Saggital view of the plain skull film showed the two crescentic calcifications symmetrically. Lateral view showed a comma-shaped calcification in the genu of the corpus callosum as well as an walnut size area of increased trancelucency in the back.

Left carotid angiogram, in saggital view, arterial phase, observed anterior cerebral artery with ir-regural dilatation penetrating into the tumor. In lateral view was observed the dilated anterior cerebral artery taking vertical course as compared to a normal case, and missing an artery equivalent to the pericallosal artery. The lateral view of the right carotid angiogram, arterial phase, revealed that the pericallosal artery dilated into the posterior portion perpendicular to the anterior cerebral artey. The lateral view of the left carotid angiogram, venous phase, showed well-developed anterior caudiate vein dislocating upward and the septal vein downward, almost surrounding from both sides the tumor itself.

The finding of PEG performed simultaneously with the left carotid angiogram revealed the wide separation of the lateral ventricles as well as the elevation of the third ventricle.

Pre-operative diagnosis had been lipoma. Biopsy was performed 18 days after the hospitalization by the right frontal craniotomy. Lipoma was thus confirmed histologically. At operation the tumor capsule was yellow and hard. In the yellow tissue, numerous arterioles were observed penetrating.

After the operation the patient was administered with anticonvulsant and her epilepsy was well controlled. She attends school but still has urinary disturbance.

Post operative prognosis of lipoma in the corpus callosum is negative. The reason for this is that the anomalous anterior cerebral artery, because it is penetrating into the tumor, tends to be ligated during removing the tumor.

We studied 18 cases, including ours, of lipoma of the corpus callosum. Their clinical data demon-strated that the removal of the tumor was not recommendable, except for a most serious case from neurological viewpoint.