Prospective anthropometric analysis of sagittal orbital-globe relationship following fronto-orbital advancement in childhood

Fronto-orbital advancement is a common procedure for correction of supraorbital retrusion in patients with coronal craniosynostosis. The aim of this study was two-fold: to quantitate change in the sagittal orbital-globe relationship following fronto-orbital advancement in childhood and to determine the ratio of skeletal-to-soft tissue movement. Soft-tissue points on the orbital rim, orbitale superius (os), orbitale laterale (ol), orbitale inferius (oi), and nasion (n), referenced to apex corneae (ac), were measured preoperatively and postoperatively by a custom-made anthropometer. Intraoperative bony advancement was measured with a caliper. Patients were selected with uniform advancement at the fronto-nasal suture and laterally at the mortise and tenon. Fifteen patients with syndromic craniosynostosis were included in the study (six male, nine female): Apert (n = 2), Crouzon (n = 5), Pfeiffer (n = 4), Saethre-Chotzen (n = 3), and Boston type (n = 1). Average age at operation was 8.7 years (range, 4.5 to 10.5 years). Age, sex, method of fixation, postoperative interval, diagnosis, and skeletal movement were analyzed for possible effect on the magnitude of soft-tissue advancement. Average intraoperative skeletal advancement was 12.1 mm, and average postoperative soft-tissue movement was 10.3 mm (p < 0.001), measured at the midpoint of the supraorbital rims (os). The soft tissue: skeletal movement ratio was 0.9:1. Os was the only point at which soft-tissue advancement could be predicted (Spearman's rank correlation coefficient = 0.67); soft-tissue changes at ol, oi, and n were unpredictable. Skeletal movement was the only determinant of soft-tissue advancement of all variables tested, i.e., diagnosis, age, sex, previous fronto-orbital advancement, and wire versus plate fixation. We make recommendations for calculating the magnitude of fronto-orbital advancement, based on preoperative anthropometry and a soft-to-hard tissue advancement factor.