Skeletal expansion via craniofacial distraction osteogenesis technique in syndromic craniosynostosis: impact on ophthalmic parameters.

BACKGROUND: This study aims to compare the changes in ophthalmic parameters among syndromic craniosynostosis patients who underwent craniofacial skeletal expansion procedures via distraction osteogenesis (DO). METHOD: A retrospective study was conducted involving syndromic craniosynostosis patients who underwent surgical expansion via the DO technique from the year 2012 to March 2022. Changes in six parameters which consist of visual acuity, refractive error, optic disc health, intraocular pressure, degree of proptosis and orbital volume were measured objectively pre and post-surgery. For categorical parameters, the Chi-square cross-tab test was done. Paired sample T-test was used for normally distributed variables. Wilcoxon signed-rank test was used for non-normally distributed data. RESULTS: Visual impairment was present in 21.4% of eyes before surgery and increased to 28.5% post-surgery. Three patients had changes of refractive error post-surgery with one developed hypermetropia, another developed anisometropia and the last had improvement to no refractive error. Two patients had optic disc swelling which was resolved post-surgery. Intraocular pressure changes were inconsistent post-surgery. All patients achieved a significant reduction in the degree of proptosis post-surgery. Orbital volume calculation using computed tomography (CT) scans shows a significant increase in volume post-surgery for all patients. CONCLUSION: Our study shows a significant increase in orbital volume post-surgery with a reduction in the degree of proptosis. Optic disc and nerve health improved after the surgery. Changes in terms of visual acuity, refractive error and IOP were inconsistent after the surgical intervention.

Severe midface and maxillary hypoplasia in non-cleft and non-syndromic patients: A 2-stage surgical strategy using distraction osteogenesis and orthognathic surgery.

Severe midface and maxillary hypoplasia can have an impact on an individual, either on the appearance, functions or psychologically. Based on literature review, severe maxillary hypoplasia with more than 25.0 mm reverse overjet in non-cleft and non-syndromic patients is very rare. It is more often seen in cleft lip and palate and syndromic patients. When the magnitude of correction exceeds the limit of what a single orthognathic surgery can achieve, multiple surgeries would be required, involving different surgical techniques. The authors report two rare cases of non-syndromic nor cleft severe hypoplastic midface and maxilla with 26.0 mm and 27.0 mm reverse overjet, respectively, treated with 2-stage surgery involving maxillary distraction osteogenesis and orthognathic surgery. Both cases recorded reasonably clinical and functional outcomes. The significance of both surgical interventions is further discussed.