S2-14 SESSION 2: POSTERIOR VAULT DISTRACTION QUANTITATIVE OUTCOMES IN POSTERIOR AND TRANSVERSE CRANIAL VAULT DISTRACTION FOR CRANIOSYNOSTOSIS

Abstract

Introduction: CVD osteogenesis has been shown to establish greater cranial volume overall than conventional remodeling. Quantitative measurement with systematic evaluation of outcomes is vital for the comparison of surgical outcomes across international institutions. Computed tomography (CT) or magnetic resonance imaging (MRI) in addition to image analysis software has been increasingly used in recent times to predict ICV changes after cranial vault surgery. The primary study aim was to quantify ICV increase in CVD and secondarily to gauge acceptability of using a simple modality to measure ICV. Methods: A retrospective review of a prospectively maintained database of posterior and transverse cranial vault distraction procedures at the National Paediatric Craniofacial Centre in Temple Street Children’s University Hospital from May 2010 to September 2016 was performed. ICV was calculated using Osirix® Version 3.3 from post-operative CT-scans. Cephalometric analysis was also performed using lateral and anteroposterior radiographic views of the cranium. Data was analyzed with GraphPad Prism®. Results: 21 patients (9 PCVD and 13 TransCVD), underwent successful cranial vault distraction. Patients in the PCVD group achieved a mean ICV increase of 2947mm, 32.5% (range: 12.8% to 80.2%, p<0.0001).95% CI 2135 to 3758mm3. In the TransCVD group, an average ICV increase of 1912.96,15.8% (range: 4.4% to 24.2%, p<0.0001) was achieved. 95% CI 1507 to 2320 mm3. Cephalic index values moved towards normal range, average change of 10.1% (range: 2.04% to 19.83%, p<0.0552) in the PVD group and 6.8% in the TransCVD (range: 2.7% to 14.8%, p<0.0001) respectively. Conclusion: This institutional review of outcomes post cranial vault distraction for syndromic and non-syndromic synostosis contributes to the existing literature and confirms the satisfactory reliable results afforded by distraction surgery along with a favorable morbidity profile. Quantitative analysis of cranial vault expansion by distraction has shown a reproducible increase in total ICV and is an effective method for rapid expansion of ICV with normalization of head morphology. We found Osirix® used with CT scans an acceptable modality that does not compromise accuracy and confer excellent interactive user-software interface.