Quantitative approach to the posterior cranial fossa and craniocervical junction in asymptomatic children with achondroplasia.

Our analysis demonstrates a relationship between the shortening of the clivus and the ventriculomegaly. On the other hand the premature closure of PCF synchondroses, the shape, and the growth direction of supraocciput bone contribute to reduce the FM area, causing in some patients medullary compression.