title: Schwannoma in head and neck: preoperative imaging study and intracapsular enucleation for functional nerve preservation.
abstract: OBJECTIVE
  In treating schwannoma patients, it is critical to determine the origin of the tumor to preserve nerve function. We evaluated the validity of preoperative imaging studies in distinguishing the neurological origin of the schwannomas of the head and neck, and the efficacy of intracapsular enucleation in preserving nerve function.
  
  
  METHODS
  In 7 cases of schwannomas in the head and neck region, we predicted whether the tumor originated from the vagus nerve or the cervical sympathetic chain through imaging studies including computed tomography (CT) and magnetic resonance imaging (MRI). All patients were performed intracapsular enucleation, and the function of the vagus nerve and the sympathetic nerve was evaluated preoperatively and postoperatively.
  
  
  RESULTS
  Preoperative imaging studies showed 6 cases where the tumor was located between the carotid artery and the internal jugular vein, and 1 case where the tumor was located posteriorly, displacing the carotid artery and the internal jugular vein anteriorly. At the time of operation, we confirmed schwannoma originating from the vagus nerve on the first 6 cases, and schwannoma originating from the sympathetic nervous system on the last case. All patients went through successful intracapsular enucleation, and of the seven schwannoma cases, 6 patients maintained normal postoperative neurological function (85.7%).
  
  
  CONCLUSIONS
  Preoperative imaging studies offer valuable information regarding the location and origination of the tumor, and intracapsular enucleation helped us to preserve the nerve function.
authors.affiliation: Department of Otorhinolaryngology, Yonsei University College of Medicine, Gangnam Severance Hospital, Gangnam-gu, Seoul, Korea.
authors.forename: Si Hong
authors.initials: SH
authors.lastname: Kim
authors.forename: Na Hyun
authors.initials: NH
authors.lastname: Kim
authors.forename: Kyung Rok
authors.initials: KR
authors.lastname: Kim
authors.forename: Ja Hyun
authors.initials: JH
authors.lastname: Lee
authors.forename: Hong-Shik
authors.initials: HS
authors.lastname: Choi
mesh_terms: D000368:Aged; D003952:Diagnostic Imaging / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006258:Head and Neck Neoplasms / Q000150:complications / Q000175:diagnosis / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009442:Neurilemmoma / Q000150:complications / Q000175:diagnosis / Q000473:pathology*; D017933:Peripheral Nervous System / Q000293:injuries / Q000502:physiology; D013564:Sympathetic Nervous System / Q000502:physiology; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome; D014630:Vagus Nerve / Q000502:physiology