Abstract
Cystic meningiomas are rare. The authors presented a case of cystic meningioma in the right frontal convexity of a 36-year-old female. The patient was admitted because of progressive headache, foggy sight, diplopia, and left-sided motor weakness of two months' duration. The preoperative diagnosis of cystic meningioma was made by plain skull X-rays, CT scans, and cerebral arteriograms. At surgery, a tumor was found adherent to the dura in the right frontal convexity with multiloculated intratumoral cysts containing xanthochromic fluid. Histologically, the tumor was a transitional meningioma with intratumoral infarction in the vicinity of the cysts. The pathogenesis of the intratumoral cysts in this particular case were considered intratumoral infarction resulting in microcysts and then finally macrocysts.
Ninety-six cases of cystic meningiomas reported in the literature were reviewed and the pathogenesis of cyst formation was discussed. Nauta's classification of four types of cystic meningiomas is important when considering the different pathogenesis of cyst formation in meningiomas. Adding to the four types of cystic meningiomas classified by Nauta et al., the authors suggested another type, namely, the subdural cyst mainly seen in infant meningiomas.
