title: Clear cell meningioma: clinical features, CT, and MR imaging findings in 23 patients.
abstract: BACKGROUND
  Clear cell meningioma (CCM) is a rare meningioma, with radiologic features not well characterized in literature. The purpose of this study was to describe and characterize the clinical features and imaging findings of CCM.
  
  
  METHODS
  The computed tomography (n = 16) and magnetic resonance (n = 23) images of 23 patients (12 men and 11 women; mean age, 34.6 years) were retrospectively reviewed. All of the patients underwent surgical resection. Follow-up was performed through clinical observations.
  
  
  RESULTS
  Cerebellopontine angle was the most frequently presenting location (n = 10). The tumors were isointense (n = 12) or hypointense but associated with isointense (n = 7) appearance to gray matter on T1-weighted images. However, the tumors seemed to be isointense (n = 6) or isointense and hyperintense (n = 13) on T2-weighted images. On gadolinium-enhanced T1-weighted images, heterogeneous enhancement was seen in 14 lesions. Four lesions had amorphous calcifications, 18 showed peritumoral edema, 14 had cystic areas, 2 had bone hyperostosis, and 8 manifested bone destruction. On initial surgery, 17 patients underwent complete resection, whereas 5 patients underwent subtotal resection of their tumors. The operative result for the remaining patient was unknown. Follow-up was possible in 22 patients. Eleven patients had recurrence and 2 had died.
  
  
  CONCLUSIONS
  Clear cell meningioma is a rare subtype of meningioma that occurs in younger patients and often recurs. Cerebellopontine angle is the most affected area in this series. The extent of initial surgical resection is the most important prognostic factor. In radiological studies, CCM tends to have marked heterogeneous enhancement, prominent peritumoral edema, intratumoral cystic components, and involvement of the adjacent bone.
authors.affiliation: From the *Department of Neurosurgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine; †Department of Oncology, Fudan University Shanghai Cancer Center; ‡Department of Ultrasound Medicine, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; and §Department of Neurosurgery, Wayne State University School of Medicine, Detroit, MI.
authors.forename: Xiao-Qiang
authors.initials: XQ
authors.lastname: Wang
authors.forename: Ming-Zhu
authors.initials: MZ
authors.lastname: Huang
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.forename: Feng-Bing
authors.initials: FB
authors.lastname: Sun
authors.forename: Bang-Bao
authors.initials: BB
authors.lastname: Tao
authors.forename: Bao-Hui
authors.initials: BH
authors.lastname: Feng
authors.forename: Chen-Long
authors.initials: CL
authors.lastname: Liao
authors.forename: Ryan
authors.initials: R
authors.lastname: Kochanski
authors.forename: Xu-Ming
authors.initials: XM
authors.lastname: Hua
authors.forename: Shi-Ting
authors.initials: ST
authors.lastname: Li
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008577:Meningeal Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D008579:Meningioma / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D012189:Retrospective Studies; D015996:Survival Rate; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA