title: Bilateral reversible deafness after surgery for unilateral epidermoid tumor: an unusual complication: case report.
abstract: OBJECTIVE
  We present an unusual complication of bilateral hearing loss after surgery for unilateral epidermoid tumor situated at the right pontocerebellar junction. The neurosurgeon must know the possible causes of this catastrophic complication and should take every possible measure to avoid it.
  
  
  METHODS
  A 43-year-old male patient presented with progressive hearing loss in the right ear. A radiological examination demonstrated a mass lesion at the right pontocerebellar junction. A pure tone audiogram revealed sensorineural hearing impairment of the right ear. A brainstem auditory evoked potential test confirmed this with reduced amplitudes and a prolonged I-V interval.
  
  
  METHODS
  The patient was operated on via a right paramedian suboccipital craniectomy. The tumor was completely excised, and all of the cranial nerves were preserved during the operation. Postoperatively, the patient developed total bilateral hearing loss, which improved significantly over time.
  
  
  CONCLUSIONS
  Controlled cerebrospinal fluid drainage during exposure and tumor excision may reduce the possibility of shift and traction on the neural structures and help to prevent ischemic injury. Frequent irrigation of the surgical field and minimizing the spilling of the tumor contents may reduce the risk of chemical irritation. The use of corticosteroids may also help during the postoperative period.
authors.affiliation: Department of Neurosurgery, Social Security Ankara Education and Research Hospital, Ankara, Turkey.
authors.forename: Mustafa Efkan
authors.initials: ME
authors.lastname: Colpan
authors.forename: Zeki
authors.initials: Z
authors.lastname: Sekerci
authors.forename: Caglar
authors.initials: C
authors.lastname: Berk
mesh_terms: D000328:Adult; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000601:surgery*; D003399:Craniotomy / Q000009:adverse effects*; D003638:Deafness / Q000209:etiology*; D007839:Functional Laterality; D006319:Hearing Loss, Sensorineural / Q000209:etiology*; D006801:Humans; D008297:Male; D011859:Radiography