title: [Spontaneous defects of the lateral skull base. 2. Etiology and review of the literature].
abstract: BACKGROUND
  Isolated cases of spontaneous cerebrospinal fluid otorrhea (SCFO) of temporal bone origin with or without meningo(encephalo)cele have been reported. Diagnosis is predicted on a high index of suspicion. Since meningitis may occur secondary to SCFO, optimal therapy with surgical closure of the defect should immediately be performed. This study was undertaken to evaluate the incidence, characteristics and type of SCFO in literature.
  
  
  METHODS
  We reviewed the reports on SCFO in the world literature since the first description in 1897 by Escat. Clinical presentation, gender, age and surgical management were aspects of our classification. Not included were patients with cerebrospinal fluid leak following any kind of previous temporal bone surgery, head trauma or rupture of the round window membrane.
  
  
  RESULTS
  A total of 241 CSFO in 236 patients were found to accomplish the search criteria. Gender was not found to be a risk factor. Two subtypes of SCFO exist: the majority (161 cases) developing through the tegmen tympani and a smaller number (80 cases) with a translabyrinthine SCFO. The latter group can be regarded as the childhood-type with congenital defects of the otic capsule (Mondini dysplasia) presenting with meningitis in 85% of all cases. Adulthood-type SCFO are typically located in the tegmen tympani area presenting with conductive hearing loss or otorrhea following tube placement in 86% of all cases. Recent literature recommends a combined (transmastoidal and middle fossa) approach for closure of defects in the tegmen.
  
  
  CONCLUSIONS
  Copious otorrhea through a perforated tympanic membrane or following placement of a ventilation tube, conductive hearing loss or meningitis without impairment of cochlear or vestibular function should be regarded as warning signs for an existing SCFO in adults. Children usually present with symptoms of inner ear anomalies, meningitis and loss of cochlear-vestibular function. High-resolution computer tomography is the diagnostic procedure of choice. A follow-up of several years to disclose any recurrence of SCFO or occurrence at a different area should be considered in any patient.
authors.affiliation: Klinik für HNO-Krankheiten, Kopf-, Hals- und Plastische Gesichtschirurgie, Malteser Krankenhaus St. Anna, Albertus-Magnus-Strasse 33, 47259 Duisburg. jwindfuhr@aol.com
authors.forename: J P
authors.initials: JP
authors.lastname: Windfuhr
authors.forename: K
authors.initials: K
authors.lastname: Sesterhenn
mesh_terms: D002558:Cerebrospinal Fluid Otorrhea / Q000209:etiology* / Q000601:surgery; D002559:Cerebrospinal Fluid Rhinorrhea / Q000209:etiology* / Q000601:surgery; D006801:Humans; D019291:Skull Base / Q000601:surgery