title: Petrous apex cephalocele and empty sella/arachnoid cyst coexistence: a clue for cerebrospinal fluid pressure imbalance?
abstract: OBJECTIVE
  To reveal the magnetic resonance imaging (MRI) properties of incidental petrous apex cephalocele (PAC) and coexisting empty sella-arachnoid cyst.
  
  
  METHODS
  We reviewed our archive from June 2005 to July 2008. Four patients were diagnosed with PAC (four females; age range, 41-60 years; mean, 48.5). All patients underwent MRI examination of the cranium. We evaluated the lesions for extension into the neighboring structures, content, signal intensity, enhancement, and relation to Meckel's cave, petrous apex and for the presence of empty sella.
  
  
  RESULTS
  The presenting symptoms included headache for three patients and diplopia for one patient. All patients had bilateral PAC, more prominent on one side. All lesions were centered posterolateral to the Meckel's cave. They were isointense to cerebrospinal fluid signal intensity and continuous with Meckel's cave on T1W, T2W and FLAIR sequences. In two patients, there was no diffusion restriction on diffusion-weighted MR images and the ADC map. Three patients had empty sella. One patient had arachnoid cyst.
  
  
  CONCLUSIONS
  Coexistence with empty sella-arachnoid cyst raises the possibility of cerebrospinal fluid inbalance in the etiology.
authors.affiliation: Department of Radiology, Ankara Numune Education and Research Hospital, Ankara, Turkey. gulhatip@yahoo.com
authors.forename: Hatice Gül
authors.initials: HG
authors.lastname: Hatipoğlu
authors.forename: Mehmet Ali
authors.initials: MA
authors.lastname: Cetin
authors.forename: Mehmet Ali
authors.initials: MA
authors.lastname: Gürses
authors.forename: Ergun
authors.initials: E
authors.lastname: Dağlioğlu
authors.forename: Bülent
authors.initials: B
authors.lastname: Sakman
authors.forename: Enis
authors.initials: E
authors.lastname: Yüksel
mesh_terms: D000328:Adult; D016080:Arachnoid Cysts / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology; D003937:Diagnosis, Differential; D004172:Diplopia / Q000209:etiology; D004652:Empty Sella Syndrome / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology; D004677:Encephalocele / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D006261:Headache / Q000209:etiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D011859:Radiography