title: Porencephalic cyst: a review of the literature and management of a rare cause of cerebrospinal fluid otorrhea.
abstract: OBJECTIVE
  To discuss the first reported case of spontaneous cerebrospinal fluid (CSF) otorrhea caused by a massive CSF-containing porencephalic cyst.
  
  
  METHODS
  A case report and review of the literature (MEDLINE 1962-2005).
  
  
  METHODS
  A tertiary neurotologic referral center.
  
  
  METHODS
  A 65-year-old woman with congenital hemiplegia presented with left-sided spontaneous CSF otorrhea of 4-month duration. An audiogram revealed a mixed hearing loss. High-resolution computed tomography revealed a thinning of the tegmen and epitympanum without an obvious defect. Magnetic resonance imaging revealed a massive porencephalic cyst essentially replacing the entire left cerebral hemisphere.
  
  
  METHODS
  A transmastoid approach with three-layered closure was used to successfully repair the sieve-like defects that were discovered in her tegmen.
  
  
  RESULTS
  The patient remains free of drainage, and the conductive hearing loss has resolved.
  
  
  CONCLUSIONS
  Spontaneous CSF otorrhea caused by a porencephalic cyst is an uncommon cause of conductive hearing loss that has never been reported before. Only a few cases of traumatic CSF otorrhea/rhinorrhea associated with a porencephalic cyst have been reported. A high level of suspicion, a beta2-transferrin assay, and appropriate radiographic imaging are required for diagnosis in adults without a history of trauma, meningitis, chronic ear disease, or previous ear surgery.
authors.affiliation: The Ohio Ear Institute, LLC, Columbus, Ohio, USA. eardoctor@ohioear.com
authors.forename: John M
authors.initials: JM
authors.lastname: Ryzenman
authors.forename: Vanessa S
authors.initials: VS
authors.lastname: Rothholtz
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Wiet
mesh_terms: D000368:Aged; D001927:Brain Diseases / Q000150:complications* / Q000175:diagnosis / Q000601:surgery*; D002558:Cerebrospinal Fluid Otorrhea / Q000175:diagnosis / Q000209:etiology* / Q000601:surgery*; D003560:Cysts / Q000150:complications* / Q000175:diagnosis / Q000601:surgery*; D005260:Female; D006314:Hearing Loss, Conductive / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008416:Mastoid / Q000601:surgery; D013506:Otologic Surgical Procedures / Q000379:methods*; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed