Monobloc frontofacial or le fort III distraction osteogenesis in syndromic craniosynostosis: Three-dimensional evaluation of treatment outcome and the need for central distraction

Background: The objectives of this study were to investigate the treatment effect, morphology, and volumetric outcomes of monobloc frontofacial or Le Fort III distraction osteogenesis in syndromic craniosynostosis by 3-dimensional evaluation. Materials and Methods: Nine consecutive patients underwent monobloc frontofacial or Le Fort III distraction during 2003 to 2012 were included and evaluated.The patient's evaluation is aminimumof a 4-year follow-up. Pretreatment, post-Treatment advancement, and relapse were quantified. The changes in intracranial volume, upper airway volume, globe protrusion, advancement at bilateral malar eminence, and central face were calculated from computerized tomography before and after treatment. Results: After distraction, the intracranial volume was increased by 16.4% in average, and the upper airway volume increased by 64.1%. Orbital protrusion improved by 9.9mm in the left eye and 10.5mm in the right eye in comparison to the preoperative status. Bilateral malar eminences advancement was greater than the dorsum advancement by 7.1 mm. Conclusion: The external distraction osteogenesis device caused significant technical difficulties with advancement of the midface in growing bones. The central midface did not advance as hoped for. This finding may suggest a need for modification in the distraction device in order to improve the central facial distraction vector.