Background: Non-syndromic coronal synostoses oxycephaly and brachycephaly (NSCSOB) are rare. Their natural history, surgical management, and outcome are debated.
Material and methods: We reviewed the available literature on NSCSOB. In addition, we reviewed retrospectively our experience with cases of NSCSOB, managed and operated by our joint craniofacial team since 1984. Newborns underwent perifrontal craniectomy, while infants and older children underwent fronto-orbital advancement with frontoparietal remodeling. Cases with delayed onset of faciosynostosis were excluded.
Results: Some cases of NSCSOB present at birth or even prenatally with gross dysmorphism and severe brachycephaly; others present later in life with harmonious restriction of intracranial volume and are at risk for development and vision. Some NSCSOB evolve from initially unisutural synostoses. We treated 61 cases, operated aged 1.4 to 106.7 months, 30 with brachycephaly and 31 with oxycephaly. Twelve of these (19.7 %), had been treated initially for sagittal or unicoronal synostosis, and evolved into NSCSOB. Intracranial hypertension was present initially in 28 (45.9 %), with ophthalmological consequences in 13 (21.3 %) and mental retardation in 6 (9.6 %). No patient had hydrocephalus; only two had asymptomatic Chiari malformation. The mean postoperative follow-up was 113.6 months. At last control, 21 patients had developmental delay and 5 had visual impairment.
Conclusions: NSCSOB are a complex entity. They have in common a high risk of severe intracranial hypertension and rare hydrodynamic complications. Genetic screening is necessary to assert their non-syndromic nature. Prolonged follow-up of all craniosynostoses is necessary because unisutural synostoses can evolve into NSCSOB, and NSCSOB can evolve into craniofaciosynostosis.