並列摘要
We report 9 cases of intracranial epidermoid tumors, one of them was a very rare type of epidermoid cyst. The mean age of patients was 46 years, 8 female, 1 male. In 7 cases the tumor was located in the CP angle cistern, and 6 of them suffered from trigeminal neuralgia, in 2 other cases it was located in the 3 rd and 4 th ventricles. All 9 cases received CT scan, and 8 of them showed low density without contrast enhancement. The other case had two kinds of density low density (26 HU) on the left side of the lesion, and high density (96 HU) on the right side. Two cases received MRI examinations. The low density on CT was found to correspond to low signal intensity on T 1 WI and high signal intensity on T 2 WI of MRI, which were typical findings of epidermoid tumor ”pearly tumor” surgically. The tumor was grossly whitish, solid and soft, and microscopically involved squmaous epithelium which the contents contained keratinous material with cholesterol crystal. The high density of the epidermoid tumor on CT was called ”dense epidermoid cysts” and corresponded to very dark (very low signal intensity) on T 2 WI of MRI, which was a true cyst grossly, containing hemosiderin and calcium soap microscopically.