title: Hearing preservation in management of epidermoids of the cerebellopontine angle: CPA epidermoids and hearing preservation.
abstract: OBJECTIVE
  Surgical approaches for epidermoid cysts of the cerebellopontine angle (CPA) are dictated by tumor location. Previous reports have advocated the sacrifice of usable hearing to achieve maximal tumor resection in a single operation. The aim of the current study is to demonstrate the applicability of hearing preservation approaches in the neurotologic management of epidermoids of the CPA.
  
  
  METHODS
  Retrospective chart review.
  
  
  METHODS
  A search of archived surgical cases at a single institution between January 1, 1997, and December 31, 2011, revealed 18 cases of epidermoid cysts involving the CPA.
  
  
  RESULTS
  Eighteen patients with a mean age 40.9 years underwent surgery. Average tumor size was 4.47 cm, and presenting symptoms included headache, vertigo, cranial neuropathies, and seizures. Thirteen patients underwent a retrosigmoid approach, 2 translabyrinthine, 2 pterional, and 1 retrolabyrinthine/presigmoid. Complications included CSF leak, pseudomeningocele, meningitis, cranial nerve dysfunction, and persistent imbalance. All but 5 patients had long-term follow-up imaging to chronicle tumor residua/recurrence, varying from 6 to 149 months postoperatively. The average length of follow-up was 71.4 months, and residual tumor was common, with most patients demonstrating a focal or small area of residual tumor on follow-up imaging. Two patients had undergone previous surgery for epidermoid excision elsewhere. Two patients required reoperation for epidermoid regrowth, and the times between surgeries were 44 and 78 months. Of the patients who underwent a retrosigmoid approach, 9 had postoperative audiograms. All of these patients maintained hearing at or near their preoperative level except for 2 patients whose hearing declined and one whose hearing significantly improved.
  
  
  CONCLUSIONS
  Hearing preservation approaches for epidermoids of the CPA is a feasible option for long-term control of these tumors. Resection from a retrosigmoid approach can provide years of useful hearing, and the majority of patients do not require reoperation.
authors.affiliation: University of California at San Diego Medical Center, San Diego, California, USA. mem001@ucsd.edu
authors.forename: Mia E
authors.initials: ME
authors.lastname: Miller
authors.forename: Bill
authors.initials: B
authors.lastname: Mastrodimos
authors.forename: Roberto A
authors.initials: RA
authors.lastname: Cueva
mesh_terms: D000328:Adult; D001301:Audiometry, Pure-Tone; D002526:Cerebellar Diseases / Q000150:complications / Q000473:pathology / Q000601:surgery*; D002530:Cerebellopontine Angle / Q000473:pathology / Q000601:surgery*; D004172:Diplopia / Q000209:etiology; D004814:Epidermal Cyst / Q000150:complications / Q000473:pathology / Q000601:surgery*; D005155:Facial Nerve Diseases / Q000209:etiology; D005260:Female; D006261:Headache / Q000209:etiology; D006309:Hearing / Q000502:physiology*; D034381:Hearing Loss / Q000453:epidemiology* / Q000517:prevention & control; D006801:Humans; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000009:adverse effects / Q000379:methods*; D011183:Postoperative Complications / Q000453:epidemiology* / Q000517:prevention & control; D012086:Reoperation / Q000706:statistics & numerical data; D012189:Retrospective Studies; D014012:Tinnitus / Q000209:etiology; D014717:Vertigo / Q000209:etiology; D055815:Young Adult