title: Vestibular orientation for craniofacial surgery: application to the management of unicoronal synostosis.
abstract: BACKGROUND
  Standardized cephalometric measurements are necessary to compare skulls of different ages and sizes, in normal and diseased subjects, and in different species. In diseases involving the skull base, classical cephalometry is often impossible because the cranial landmarks are modified. In vestibular orientation (VO), the plane of the lateral semicircular canal (LSCC) of the inner ear, which has a constant relation to gravity, defines the horizontal plane of reference. Defining a reference plane independent of external landmarks is especially important in unicoronal craniosynostosis (UCCS), because the skull base is asymmetrical.
  
  
  OBJECTIVE
  To illustrate the interest of VO in clinical practice, we report on our experience with VO-based correction of UCCS.
  
  
  METHODS
  Since 1992, we have used VO-3D computed tomography scanner for surgical planning of all patients with UCCS, measuring the required correction as the discrepancy between the theoretical and the observed midline.
  
  
  RESULTS
  Thirty-eight children were operated under the age of 2 years for UCCS and evaluated after a mean follow-up of 66 months. Thirty-two (84%) were considered perfect, four (11%) had mild imperfection not requiring reoperation, and two (5%) required reoperation because of progressive craniosynostosis involving the sagittal suture. Good surgical results were obtained when the orbits were correctly oriented relative to the plane of the LSCC.
  
  
  CONCLUSIONS
  VO is a useful reference system for the evaluation and surgical planning of UCCS. We hypothesize that the mismatch between the visual and labyrinthic sensorial inputs plays a role in the pathophysiology of UCCS.
authors: Department of Pediatric Neurosurgery, University Hospital, Lille, France. M-Vinchon@CHRU-LILLE.Fr
authors: Matthieu
authors: M
authors: Vinchon
authors: Philippe
authors: P
authors: Pellerin
authors: Bruno
authors: B
authors: Pertuzon
authors: Raphaël
authors: R
authors: Fénart
authors: Patrick
authors: P
authors: Dhellemmes
mesh_terms: D002508:Cephalometry / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D019465:Craniofacial Abnormalities / Q000150:complications / Q000473:pathology / Q000601:surgery; D003398:Craniosynostoses / Q000150:complications / Q000473:pathology / Q000601:surgery*; D005146:Facial Asymmetry / Q000209:etiology / Q000473:pathology / Q000601:surgery*; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional; D007223:Infant; D019651:Plastic Surgery Procedures / Q000379:methods*; D012886:Skull / Q000033:anatomy & histology* / Q000473:pathology / Q000601:surgery; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014722:Vestibule, Labyrinth / Q000033:anatomy & histology*