title: Cerebrospinal fluid leaks and encephaloceles of temporal bone origin: nuances to diagnosis and management.
abstract: OBJECTIVE
  Temporal bone encephalocele has become less common as the incidence of chronic mastoid infection and surgery for this condition has decreased. As a result, the diagnosis is often delayed, and the encephalocele is often an incidental finding. This situation can result in serious neurologic complications with patients presenting with cerebrospinal fluid leak and meningitis. We review the occurrence of, characteristics of, and repair experience with temporal encephaloceles from 2000-2012.
  
  
  METHODS
  We conducted a retrospective review of 32 patients undergoing combined mastoidectomy and middle cranial fossa craniotomy for the treatment of temporal encephalocele.
  
  
  RESULTS
  The diagnosis of temporal encephalocele was made in all patients using high-resolution temporal bone computed tomography and magnetic resonance imaging. At the time of diagnosis, 12 patients had confirmed cerebrospinal fluid leak; other common presenting symptoms included hearing loss and ear fullness. Tegmen defect was most commonly due to chronic otitis media (n = 14). Of these patients, 8 had undergone prior mastoidectomy, suggesting an iatrogenic cause. Other etiologies included radiation exposure, congenital defects, and spontaneous defects. Additionally, 2 patients presented with meningitis; 1 patient had serious neurologic deficits resulting from venous infarction.
  
  
  CONCLUSIONS
  The risk of severe neurologic complications after the herniation of intracranial contents through a tegmen defect necessitates prompt recognition and appropriate management. Computed tomography and magnetic resonance imaging aid in definitive diagnosis. A combined mastoid/middle fossa approach allows for sustainable repair with adequate exposure of defects and support of intracranial contents.
authors.affiliation: Department of Neurosurgery, New York Medical College, Valhalla, New York, USA. Electronic address: dhruve.jeevan@me.com.
authors.forename: Dhruve S
authors.initials: DS
authors.lastname: Jeevan
authors.affiliation: Department of Neurosurgery, New York Medical College, Valhalla, New York, USA.
authors.forename: D Ryan
authors.initials: DR
authors.lastname: Ormond
authors.affiliation: Department of Otolaryngology, New York Medical College, Valhalla, New York, USA.
authors.forename: Ana H
authors.initials: AH
authors.lastname: Kim
authors.affiliation: Department of Otolaryngology, New York Medical College, Valhalla, New York, USA.
authors.forename: Lawrence Z
authors.initials: LZ
authors.lastname: Meiteles
authors.affiliation: Department of Otolaryngology, New York Medical College, Valhalla, New York, USA.
authors.forename: Katrina R
authors.initials: KR
authors.lastname: Stidham
authors.affiliation: Department of Otolaryngology, New York Medical College, Valhalla, New York, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Linstrom
authors.affiliation: Department of Neurosurgery, New York Medical College, Valhalla, New York, USA.
authors.forename: Raj
authors.initials: R
authors.lastname: Murali
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D065634:Cerebrospinal Fluid Leak / Q000175:diagnosis* / Q000209:etiology / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D004677:Encephalocele / Q000150:complications / Q000175:diagnosis* / Q000601:surgery*; D005260:Female; D034381:Hearing Loss / Q000209:etiology; D006801:Humans; D008297:Male; D008416:Mastoid / Q000601:surgery; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000379:methods; D010033:Otitis Media / Q000150:complications; D011183:Postoperative Complications / Q000453:epidemiology; D012189:Retrospective Studies; D013701:Temporal Bone; D055815:Young Adult
keywords: Cerebrospinal fluid leak; Cranial fossa; Encephaloceles; Hearing; Middle cranial fossa; Surgery; Temporal bone; Transmastoid