title: Endoscopic image-guided transcervical odontoidectomy:  outcomes of 15 patients with basilar invagination.
abstract: BACKGROUND
  Ventral decompression with posterior stabilization is the preferred treatment for symptomatic irreducible basilar invagination. Endoscopic image-guided transcervical odontoidectomy (ETO) may allow for decompression with limited morbidity.
  
  
  OBJECTIVE
  To describe the perioperative outcomes of patients undergoing anterior decompression of basilar invagination with the use of ETO.
  
  
  METHODS
  Fifteen patients who had a follow-up of at least 16 months were retrospectively reviewed. Intraoperatively, the vertebral body of C2 was removed and the odontoid was resected in a "top-down" manner using endoscopic visualization and frameless stereotactic navigation. Posterior instrumented stabilization was subsequently performed.
  
  
  RESULTS
  The average (± standard deviation) age of the patients was 42.6 ± 24.5 (range, 11-72) years. Postoperative complications occurred in 6 patients, including a urinary tract infection (n = 2), upper airway swelling (n = 2), dysphagia (n = 2), gastrostomy tube placement (n = 1), and an asymptomatic pseudomeningocele (n = 1). No patients required a tracheostomy, had bacterial meningitis, or developed a venous thromboembolic event; only 1 patient was intubated for more than 48 hours postoperatively. With a mean follow-up of 41.9 ± 14.4 (range, 16-59) months, myelopathy improved in all patients and no patient experienced late neurological deterioration. The mean modified Japanese Orthopedic Association (JOA) score increased from 11.2 ± 4.2 to 15.9 ± 1.4 (P = .002). Patients with a diagnosis other than rheumatoid arthritis or who had a higher preoperative JOA score had a significantly better postoperative neurological recovery (P = .005).
  
  
  CONCLUSIONS
  ETO may be a valid treatment for patients with symptomatic irreducible basilar invagination that avoids some of the morbidity of transoral surgery and leads to long-term improvement in myelopathy.
authors.affiliation: School of Medicine, Johns Hopkins University, Baltimore, Maryland 21287, USA.
authors.forename: Hormuzdiyar H
authors.initials: HH
authors.lastname: Dasenbrock
authors.forename: Michelle J
authors.initials: MJ
authors.lastname: Clarke
authors.forename: Ali
authors.initials: A
authors.lastname: Bydon
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Sciubba
authors.forename: Timothy F
authors.initials: TF
authors.lastname: Witham
authors.forename: Ziya L
authors.initials: ZL
authors.lastname: Gokaslan
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Wolinsky
mesh_terms: D000328:Adult; D000368:Aged; D002648:Child; D019299:Decompression, Surgical / Q000009:adverse effects / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D044583:Neuroendoscopy / Q000009:adverse effects / Q000379:methods*; D038361:Neuronavigation / Q000009:adverse effects / Q000379:methods*; D009809:Odontoid Process / Q000601:surgery*; D010985:Platybasia / Q000601:surgery*; D011183:Postoperative Complications / Q000453:epidemiology; D012189:Retrospective Studies; D055815:Young Adult