A Retrospective Cohort Study of 5-Year Aesthetic Outcomes: Fronto-orbital Distraction Osteogenesis Versus Fronto-orbital Advancement & Remodeling

Abstract

INTRODUCTION: Unicoronal craniosynostosis (UCS) phenotypically presents with ipsilateral frontal and parietal bone flattening, supraorbital rim elevation and recession, temporal retrusion, palpebral fissure widening, and vertical orbital dystopia – known as the ‘harlequin deformity.’ Fronto-orbital advancement and remodeling (FOAR) is currently the most common surgical approach for UCS, although outcomes suggest high rates of ocular dysfunction, failure to achieve long-term aesthetic normalcy, and relapse over time. Fronto-orbital distraction osteogenesis (DO) is an alternative treatment for UCS, with literature suggesting improved anterior cranial base deviation, decreased perioperative morbidity, and lower rates of ocular dysmotility. This study compared long-term objective photogrammetric aesthetic and postoperative outcomes of patients with UCS treated with DO and FOAR. METHODS: Patients presenting with non-syndromic UCS between 2007 and 2021 undergoing DO were compared to a matched cohort of patients undergoing FOAR. Clinical photographs and ImageJ were used to quantify palpebral fissure height and width, pupil-to-brow distance (PTB), and margin-reflex distance (MRD1) in pixels. The formula symmetry ratio = - [|(1 - (s/n)| × 100] was used to compare synostosed (s) and nonsynostosed (n) sides, where a symmetry ratio value of ‘0’ indicated perfect symmetry, and lower (more negative) symmetry ratio values indicated increased asymmetry. Positive differences in pre- and post-operative symmetry ratios indicate improved symmetry. The difference in canthal tilt angles was calculated with canthal tilit angle = |(s - n)|. Whitaker classification was assigned in a blinded fashion by two attending craniofacial surgeons. Statistical analysis was performed with unpaired t-tests. RESULTS: Forty patients (ten males) were included. The average age at surgery for FOAR and DO groups was 9.4 vs. 6.5 months (p < 0.001) and average length of follow up was 6.0 vs. 5.1 years (p = 0.456), respectively. Photogrammetric analysis and unpaired t-tests demonstrated significantly improved postoperative symmetry in the DO cohort for palpebral width [FOAR: -2.24, DO: 3.07 (p = 0.020)], MRD1 [FOAR: -9.92, DO: 12.87, (p = 0.045)], and canthal tilt [FOAR: 0.97°, DO: 6.54°, (p = 0.010)]. Analysis did not reveal significant symmetry ratio improvement in palpebral height (p = 0.157) and PTB (p = 0.202) between DO and FOAR cohorts. Unpaired t-tests revealed no significant difference in Whitaker Classification scores between FOAR and DO cohorts, with average scores of 1.97 ± 0.56 and 1.78 ± 0.54, respectively (p = 0.394). CONCLUSION: Photogrammetric analysis of the periorbital region in UCS patients five years after surgery reveals significant improvement in those treated with both FOAR and DO, with DO patients demonstrating superior results in palpebral width and canthal tilt symmetry. However, patients treated with DO achieved similar Whitaker Classification compared to their FOAR counterparts. It will be important to continue to follow these cohorts to craniofacial maturity prior to making any definitive conclusions.