Characterization of Regional Morphological Changes in Metopic Craniosynostosis Following Endoscopic Strip Craniectomy With Postoperative Helmeting: Predictors for Success

Abstract

Background: Metopic craniosynostosis (MC) represents 10% to 25% of craniosynostosis cases. Endoscopic-assisted strip craniectomy (ESC) with orthotic molding therapy provides a minimally invasive alternative to open fronto-orbital advancement. Herein, we describe a 3D photogrammetry methodology for measurement of regional cranial growth and inter-frontal angle (IFA) as well as examine factors that may contribute to successful outcomes after ESC. Methods: A retrospective review was performed on patients with MC treated with ESC and band therapy from 2015 to 2019. Patients obtained 3D photogrammetry preoperatively, postoperatively, and post-helmet therapy. A survey was administered to 14 independent raters, who were asked to determine treatment success based on subjective visual assessment of preoperative and post-banding images. Patients were considered to have successful therapy when ≥75% of raters were in agreeance. Results: Thirteen patients met inclusion criteria. Average age at surgery was 3.5 months, with 53.9% of these patients deemed as a successful outcome on aggregate reviewer scores. For patients with successful treatment, there was a trend toward younger at surgery (2.9 months vs 4.2 months, P = .09) and at initiation of helmeting (3.3 months vs 4.8 months, P = .07). Regional root mean square identified significant differences between frontal and temporal (14.04 mm vs 7.39 mm, P = .02) and temporal and parietal (7.39 mm vs 15.37 mm, P = .002) regions. Average postoperative IFA was significantly improved compared to preoperative values (128.19° vs 117.9°, P = .02). Logistic regression modeling found no significant predictors of success. Discussion: Though not statistically significant, patients with MC with successful outcomes following ESC and banding were younger at surgery and time of helmeting. Our analysis of regional cranial growth and IFA demonstrated significant differences, which coincide with expected morphologic changes in this patient population. Our results demonstrate the potential for this technology in surgical evaluation and support the importance of early diagnosis and treatment by craniofacial surgeons.