title: Facial Nerve Function and Quality of Resection in Large and Giant Vestibular Schwannomas Surgery Operated By Retrosigmoid Transmeatal Approach in Semi-sitting Position with Intraoperative Facial Nerve Monitoring.
abstract: BACKGROUND
  Large and giant vestibular schwannomas pose a real problem in their management. The preservation of facial nerve function may limit tumor resection despite the use of intraoperative monitoring of the facial nerve. In Algeria, vestibular schwannomas represent 5% of all intracranial tumors operated on, 80.5% of which are large or giant.
  
  
  METHODS
  From January 2010 to December 2015, 151 large and giant vestibular schwannomas were operated in our department. Tumor diameter was between 30 and 60 mm. The most common presenting symptom was hearing loss, which was observed in 41.66% of all our patients. All patients were operated in the semi-sitting position with opening of the posterior wall of the internal auditory canal and under continuous intraoperative facial nerve function monitoring.
  
  
  RESULTS
  Tumor resection was total in 126 patients. Anatomic preservation of the facial nerve was the reason for nontotal resection in 25 patients. The facial nerve was anatomically preserved in 149 patients. Two years after surgery, the facial nerve function was grade I-II House-Brackmann (H-B) score in 124 cases (82%), grade III-IV H-B score in 21 cases (14%), and grade V-VI H-B score in 06 cases (04%). The status and the improvement of postoperative facial nerve function depend on 4 factors: anatomic preservation of nerve, stimulation threshold, cystic form, and the presence of train activity.
  
  
  CONCLUSIONS
  The development of anesthesia techniques and microsurgery and the systematic use of intraoperative monitoring of the facial nerve have allowed us to move from a life preservation era to another era of preservation of function.
authors.affiliation: Neurosurgery Department, Ali Ait Idir Specialized Hospital, Algiers, Algeria. Electronic address: lotfiboublata@gmail.com.
authors.forename: Lotfi
authors.initials: L
authors.lastname: Boublata
authors.affiliation: Neurosurgery Department, Ali Ait Idir Specialized Hospital, Algiers, Algeria.
authors.forename: Mohamad
authors.initials: M
authors.lastname: Belahreche
authors.affiliation: Neurosurgery Department, Ali Ait Idir Specialized Hospital, Algiers, Algeria.
authors.forename: Rafik
authors.initials: R
authors.lastname: Ouchtati
authors.affiliation: Neurosurgery Department, Ali Ait Idir Specialized Hospital, Algiers, Algeria.
authors.forename: Zarina
authors.initials: Z
authors.lastname: Shabhay
authors.affiliation: Neurosurgery Department, Ali Ait Idir Specialized Hospital, Algiers, Algeria.
authors.forename: Leila
authors.initials: L
authors.lastname: Boutiah
authors.affiliation: Neurosurgery Department, Ali Ait Idir Specialized Hospital, Algiers, Algeria.
authors.forename: Mohamad
authors.initials: M
authors.lastname: Kabache
authors.affiliation: Neurosurgery Department, Ali Ait Idir Specialized Hospital, Algiers, Algeria.
authors.forename: M'hamed
authors.initials: M
authors.lastname: Nadji
authors.affiliation: Neurosurgery Department, Batna University Hospital, Batna, Algeria.
authors.forename: Zoheir
authors.initials: Z
authors.lastname: Djenna
authors.affiliation: Epidemiology Department, Batna University Hospital, Batna, Algeria.
authors.forename: Hocine
authors.initials: H
authors.lastname: Bounecer
authors.affiliation: Neurosurgery Department, Ali Ait Idir Specialized Hospital, Algiers, Algeria.
authors.forename: Nafa
authors.initials: N
authors.lastname: Ioualalen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000462:Algeria; D005154:Facial Nerve; D020220:Facial Nerve Injuries / Q000209:etiology / Q000503:physiopathology* / Q000517:prevention & control; D005260:Female; D020233:Gait Disorders, Neurologic / Q000209:etiology; D034381:Hearing Loss / Q000209:etiology; D006801:Humans; D064795:Intraoperative Neurophysiological Monitoring / Q000379:methods*; D008297:Male; D008866:Microsurgery / Q000379:methods*; D008875:Middle Aged; D018365:Neoplasm, Residual; D009464:Neuroma, Acoustic / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D019635:Neurosurgical Procedures / Q000009:adverse effects / Q000379:methods*; D056888:Patient Positioning; D011183:Postoperative Complications / Q000209:etiology / Q000503:physiopathology* / Q000517:prevention & control; D012189:Retrospective Studies; D014012:Tinnitus / Q000209:etiology; D014057:Tomography, X-Ray Computed; D047368:Tumor Burden; D055815:Young Adult
keywords: Facial nerve function; Intraoperative facial nerve monitoring; Quality of resection; Vestibular schwannoma