Vestibular orientation for craniofacial surgery: application to the management of unicoronal synostosis.
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.
Vinchon
Matthieu
M
Department of Pediatric Neurosurgery, University Hospital, Lille, France. M-Vinchon@CHRU-LILLE.Fr
Pellerin
Philippe
P
Pertuzon
Bruno
B
Fénart
Raphaël
R
Dhellemmes
Patrick
P
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*