title: Facial and Cochlear Nerve Complications following Microsurgical Resection of Vestibular Schwannomas in a Series of 221 Cases.
abstract: BACKGROUND
  Despite improvements in microsurgical technique and the use of intraoperative electrophysiological monitoring, the potential for facial and cochlear nerve injury remains a possibility in the resection of vestibular schwannomas (VS). We reviewed a series of 221 cases of VS resected via a retrosigmoid approach at our institution from October 2008 to April 2014 and determined the incidence of postoperative facial and cochlear deficits.
  
  
  METHODS
  A total of 221 patients - 105 (47.5%) male and 116 (52.5%) female - with a mean age of 46.1 years (range 29-73 years), with VS ≥3 cm (n=183, 82.8%) and <3 cm (n=38, 17.2%) underwent surgical resection via a retrosigmoid approach and were evaluated for postoperative facial and cochlear nerve deficits.
  
  
  RESULTS
  Near-total resection (>95% removal) was achieved in 199 cases (90%) and subtotal resection (>90% removal) in 22 cases (10%). At 6 month follow-up, House-Brackmann grades I-III were observed in 183 cases (82.8%), grade IV in 16 cases (7.2%), and grade V in 22 cases (10%). Of the 10 patients that had preoperative functional hearing, 3 (33%) retained hearing postoperatively. Cerebrospinal fluid leakage occurred in 6 patients (2.7%), lower cranial nerve palsies in 9 patients (4.1%), and intracranial hematomas 3 cases (1.4%).
  
  
  CONCLUSIONS
  The observed incidence of persistent postoperative nerve deficits is very low. Meticulous microsurgical dissection of and around the facial and cochlear nerves with the aid of intraoperative electrophysiological nerve monitoring in the retrosigmoid approach allows for near-total resection of medium and large VS with the possibility of preservation of facial and cochlear nerve function.
authors.affiliation: Department of Neurosurgery, General Hospital of the People's Liberation Army, Beijing, China (mainland).
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Neurosurgery, General Hospital of the People's Liberation Army, Beijing, China (mainland).
authors.forename: Bai-Nan
authors.initials: BN
authors.lastname: Xu
authors.affiliation: Department of Neurosurgery, General Hospital of the People's Liberation Army, Beijing, China (mainland).
authors.forename: Yuan-Zheng
authors.initials: YZ
authors.lastname: Hou
authors.affiliation: Department of Neurosurgery, General Hospital of the People's Liberation Army, Beijing, China (mainland).
authors.forename: Guo-Chen
authors.initials: GC
authors.lastname: Sun
authors.affiliation: Department of Neurosurgery, General Hospital of the People's Liberation Army, Beijing, China (mainland).
authors.forename: Yan
authors.initials: Y
authors.lastname: Jiang
mesh_terms: D000328:Adult; D000368:Aged; D003056:Cochlear Nerve / Q000293:injuries*; D020220:Facial Nerve Injuries / Q000209:etiology / Q000473:pathology*; D005260:Female; D006801:Humans; D064795:Intraoperative Neurophysiological Monitoring / Q000379:methods; D008297:Male; D008866:Microsurgery / Q000009:adverse effects* / Q000379:methods; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000601:surgery*; D019635:Neurosurgical Procedures / Q000009:adverse effects*; D013506:Otologic Surgical Procedures / Q000009:adverse effects*; D016896:Treatment Outcome