Cystic meninigioma.

To study the clinical characteristics of cystic meningiomas, we analyzed retrospectively 21 patients with cystic meningiomas and reviewed the literature with regard to clinical presentation, imaging features, preoperative diagnosis, surgical findings, and histopathological results. The cysts were classified into intratumoral and peritumoral cysts based on their relationship to the tumor, and also according to the classification method described by Nauta. For the 21 patients in our group, there were seven peritumoral cysts and 14 intratumoral cysts. Various pathophysiological mechanisms contribute to the formation of cystic meningiomas. The diagnosis of cystic meningiomas based on CT scan can be problematic, and differentiation from glioma or metastasis may be difficult. MRI scans show low signal intensity areas within the mass on T1-weighted images and high signal intensity areas on T2-weighted images, and the solid parts of tumors are contrast-enhanced after gadolinium administration. MRI with gadolinium enhancement dramatically increases the diagnostic accuracy for cystic meningiomas and provides critical information for their surgical care. Total surgical resection of cystic meningioma is ideal, but special attention should be paid to the cyst walls.