Aim: Patients with syndromic craniosynostosis often suffer from shallow orbits due to midface hypoplasia. The present study aims to evaluate quantitatively the influence of Le Fort III advancement on orbital volume, position of the infra-orbital rim and globe-position.

Material and method: Pre- and postoperative CT-scans of 18 syndromic craniosynostosis patients were analyzed. In each scan, segmentation of the left and right orbit was performed and the infra-orbital rim and globe were marked. By superimposing the pre- and postoperative scan and the creation of a reference coordinate system, the movement of the infra-orbital rim and globe was evaluated.

Results: Orbital volume increased significantly ( p < 0.001) with 27.2% for the left and 28.4% for the right orbit. A significant anterior movement of the left infra-orbital rim of 12.0 mm (sd 4.2) and right infra-orbital rim of 12.8 mm (sd 4.9) were found. A significant medial movement of 1.7 mm (sd 2.2) of the left globe and 1.5 mm (sd 1.9) of the right globe were found ( p < 0.005). There was a significant correlation ( r _s = 0.498, p = 0.035 (left) and 0.642, p = 0.018 (right)), between the anterior infra-orbital rim movement and the orbital volume gain.

Summary: Significant orbital volume gain has been demonstrated after Le Fort III advancement. The position of the infra-orbital rim was significantly transferred anterior, whereas the position of the globe remained relatively unaffected.

Conflict of interest: None declared.