Skull Base Growth in Craniosynostosis

Although considerable scientific work has been published on the role of the skull base in craniosynostosis, the changes with age throughout childhood have not been fully outlined. The realisation that little attention has been paid to the posterior skull in craniosynostosis, resulted in renewed interest in skull base growth. The availability of computer-based image analysis provides a new accurate method of study in three dimensions. Using three-dimensional visualisation techniques, 34 points of the skull base were identified on CT scans of 50 children with craniosynostosis of various types, aged from 1 month to 5 years. Several distances and angles between the various landmarks were measured in an attempt to quantify the growth of skull fossae with age. Comparisons were made with normal controls. In children with craniosynostosis, the anterior fossa was overdeveloped in the males, whereas in the females remained underdeveloped throughout the first 2 years of life. The body of the sphenoid showed moderate underdevelopment in the first 2 years in both sexes, the effect being more prominent in the males. The middle fossae showed overdevelopment in both sexes in the first 2 years of life. The posterior fossa was underdeveloped in both sexes in the first 2 years of life, the effect being more prominent in the females. Craniosynostosis seems to affect both sexes to a similar degree, but there are regional differences in the growth pattern. Better understanding of the normal growth pattern of the skull base and the effect of craniosynostosis upon it may assist our approach to surgical treatment and in particular the role of anterior and posterior skull expansive surgery.