Long-Term Orbito-ocular Outcomes Following LeFort III and Monobloc Distraction Osteogenesis in Patients with Syndromic Craniosynostosis

Introduction: Exorbitism in patients with syndromic craniosynostosis is often managed by LeFort III (LF3) or Monobloc (MB) distraction osteogenesis (DO). This study compared short- and long-term orbital craniometrics after LF3DO/MBDO and related these findings to symptom relief. Methods: Patients undergoing LF3DO or MBDO from 2000-2021 with pre- and postoperative imaging were included. Postoperative CTs were categorized as early (<1 year) or late (>1 year), and age-matched control CTs were compared to late postoperative scans. Superior/inferior orbital rim position, relative globe position, and orbital volume were analyzed. Symptoms were assessed by a patient-reported outcome (PRO) analysis. Results: Thirty-four patients (16 LF3DO, 18 MBDO) were matched by age at surgery, sex, syndrome, and age at imaging. Time to late CT was 6.2 years (LF3DO) and 7.5 years (MBDO). Between early and late postoperative time points, LF3DO patients experienced no change in inferior rim position. MBDO patients experienced a decrease in inferior orbital rim position of 4.7mm (p=0.005), but superior orbital rim distance remained stable. Comparison of late scans and age-matched controls revealed no difference in inferior or superior orbital rim position in LF3DO patients, but the superior orbital rim distance was longer in MBDO patients (p=0.015). PRO response rate was 76% with a median follow up of 13.7 years. Most (81%) symptomatic patients improved, 19% remained symptomatic, and no patients worsened. Conclusions: LF3DO and MBDO achieved stable orbital craniometric changes, with improved stability at the inferior orbital rim after LF3DO. Craniometric changes were associated with long-term exorbitism symptom relief.