Preoperative and postoperative orbital volume in patients with Crouzon and Apert syndrome

Crouzon and Apert syndromes are frequently complicated by ocular abnormalities and patients with these syndromes often present with abnormal ocular morphology. The present study assesses orbital volume and ocular complications in patients associated with Crouzon and Apert syndromes.During an 8-year period starting in 2002, fronto-orbital advancement was used for cranial expansion on 23 cases of syndromic craniosynostosis. Of those, it was possible to evaluate 5 Crouzon and eight Apert syndrome cases. Orbital volume was measured using multislice CT scans. Both preoperative and postoperative orbital volumes were compared with normal orbital volume.Preoperative orbital volume was 5.8 to 10.0 cm (mean, 7.1 cm) in patients with Crouzon syndrome and 7.2 to 10.8 cm (mean, 9.1 cm) in patients with Apert syndrome. Postoperative intraorbital volume was 9.4 to 11.2 cm (mean, 10.4 cm) in patients with Crouzon syndrome and 11.6 to 13.2 cm (mean, 12.4 cm) in patients with Apert syndrome. The mean of orbital volume relative to the normal volume was 58% preoperatively and 74% postoperatively in patients with Crouzon syndrome and 69% (56-81%) preoperatively and 88% (81-95%) postoperatively in patients with Apert syndrome.In conclusion, orbital volume was smaller in the Crouzon syndrome group than in the Apert syndrome group, and symptoms, such as exophthalmos and exotropia, were noted in the Crouzon syndrome group. Orbit expansion did not fully restore normal orbital volume, but in most cases, it was useful for alleviation of preoperative symptoms (exophthalmos/eyeball prolapse, corneal erosion, conjunctivitis).