ISCFS 2019 Abstract Supplement
S7A-15 SESSION 7A: SAGITTAL SYNOSTOSIS EVALUATION OF DELAYED SAGITTAL SYNOSTOSIS BENEFITS FROM QUANTITATIVE CRANIAL SHAPE ANALYSIS
Introduction: Latent isolated sagittal craniosynostosis (ISC) typically results in scaphocephaly. Mild or even absent phenotypic changes with up to 44% incidence of raised ICP have been reported. Although cranial index (CI) in these patients appears normal, this metric may not provide a complete picture of cranial shape, and thus may not be used as a diagnostic tool in this population. The goal of this study is to better quantify the differences in cranial shape in patients with ISC using a proprietary cranial shape analysis (CSA) software.
Methods: We identified 19 patients with ISC (age 7.4 ± 2.28 years) and visibly normal head shape, who presented to our hospital between 2011 and 2016. Cranial shape was evaluated by CI measured from the CT image and by CSA, which calculates the distances between the patient’s cranial shape and its closest normal shape (from a multi-atlas of 220 healthy subjects). Adjunct to the head shape analysis, intracranial volume (ICV) was measured and compared to an established age-matched normative database from 550 healthy individuals.
Results: During the CI measurement we found fifteen patients (78.9%) that were within the mesocephalic range (CI 70 – 85) and four patients (25%) that were within the brachycephalic range (CI >85). Detailed CSA of the patients identified sixteen patients (84.2%) with abnormal head shape: fifteen (78.9%) with a variety of scaphocephalic phenotypes and one patient (5.3%) with overdevelopment malformations on the posterior part of the right parietal bone. Three patients (15.8%) had a CSA close to normal. Mean ICV was 1410.5 ±192.77 cc; the majority of patients (78.9%) fell within ± 2 standard deviations of the normative values.
Conclusion: The cranial shape in the majority of patients with latent sagittal fusion is not normal. Although most of the patients in this cohort had a normal ICV, quantitative cranial shape analysis demonstrated subtle changes that are poorly captured by visual exam or cephalic index. CSA provides a more accurate assessment of cranial malformations in patients with delayed isolated sagittal synostosis, and may provide more complete information to guide treatment options.Copyright © 2019 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of The American Society of Plastic Surgeons. All rights reserved.