硬膜に発生したosteomaの1例

Osteoma Originating in the Dura : A Case Report

I．はじめに

　Osteomaは良性の骨腫瘍であり，頭蓋内に認められるのは稀である．その中でも，骨とのatta-chmentを有さず，硬膜下・脳内に認められるosteomaは報告例が極めて少ない．今回，われわれは硬膜外表が正常であり，硬膜内面にattach-mentを有したosteomaの症例を経験したので，文献的考察を加え，報告する．

We report a case of intracranial osteoma attatched to the dura. The patient, a 35-year-old man, had suf-fered several episodes of vertigo over the previous two years. Physical and neurological findings on admis-sion were unremarkable. A plain craniogram showed a dense calcified mass in the right frontal area, andCT revealed a homogeneous high-density mass without significant enhancement. MRI confirmed the duralorigin of the lesion, which showed hyperintensity in the T1-weighted image and low intensity in the T2-weighted image. The mass was 5cm in diameter and 2cm in thickness. Total resection was performedunder a preoperative diagnosis of calcified meningioma. Histopathology revealed the mass to be an ost-eoma.

Osteomas are common benign bone tumors that usually arise from long bones of the extremities. In-tracranial osteomas are extremely rare lesions. The literature on intracranial osteoma of dural origin is re-viewed.