Longitudinal study of the neurodevelopmental characteristics of treated and untreated nonsyndromic craniosynostosis in infancy

Purpose: Nonsyndromic craniosynostosis (NSC) are a group of congenital disorders sharing premature fusion of one or more of the cranial sutures that restricts and distorts growth of the skull and underlying brain. This study examined the neurodevelopmental sequelae of NSC both prior to and following reconstructive cranial surgery. Methods: Sixty-four consecutive referrals with mixed forms of untreated NSC aged 4 to 16 months (M = 8.9, SD = 2.9) comprised the pre-operative cohort. Forty-four of these patients aged 6 to 32 months (M = 21.2, SD = 4.5) underwent post-operative developmental evaluation. Neurodevelopmental function was assessed with the mental (Mental Development Index) and motor (Psychomotor Development Index) scales of the Bayley Scales of Infant Development - 2nd edition. Results: Children with untreated NSC displayed significantly lower mental (M = 97.5) and motor (M = 87.7) scores than normative expectations, with the distribution of scores also differing significantly from the normative distribution. Post-operatively, children continued to display significantly lower mental (M = 89.5) and motor (M = 88.0) abilities, with mental abilities falling significantly lower than pre-operative levels. An increased prevalence of severe motor delay was found, and no child displayed accelerated development. Subgroup comparisons revealed no differences in mental or motor skills between the primary diagnostic subtypes (sagittal and metopic synostosis) both prior to and following corrective surgery. Conclusions: NSC is associated with an increased incidence of developmental delay in both treated and untreated conditions. Timing of surgery appears unrelated to developmental outcome.