Intellectual Outcomes in Children and Adolescents with Syndromic and Nonsyndromic Craniosynostosis

Abstract

Craniosynostosis, the premature fusion of the skull bones, is a congenital deformity that has functional and morphologic implications. Cranial vault reconstructive surgery is required to improve skull shape and increase intracranial volume. Craniosynostosis disorders carry a risk of brain insult and associated neurologic and cognitive dysfunction. This study investigated the long-term effects of craniosynostosis on intelligence in children and adolescents with syndromic and nonsyndromic disorders who had undergone cranial expansion surgery during infancy. Global intellectual evaluations were obtained on 31 children aged 7 to 16 years with mixed syndromic (n = 13) and nonsyndromic (n = 18) craniosynostoses. Results of intellectual assessment were compared with norm-referenced data. Age at surgery and gender comparisons were also made. Mean +/- SD general intelligence quotient of the total sample was within the average range (intelligence quotient, 95.6 +/- 21.2). Intellectual functioning was significantly lower in children with syndromic craniosynostosis (mean intelligence quotient, 83.1 +/- 21.9) than nonsyndromic craniosynostosis (mean intelligence quotient, 104.7 +/- 15.8). The majority of children with syndromic craniosynostosis (77 percent) were of normal intelligence. Children with nonsyndromic craniosynostosis did not display obvious evidence of intellectual dysfunction. There were no age or gender differences in intellectual outcomes in this sample. Findings are contrary to the historical impression that has regarded syndromic craniosynostosis as synonymous with intellectual disability. Children with nonsyndromic craniosynostosis are of normal intelligence during their school-age years.