The role of the posterior fossa in developing Chiari I malformation in children with craniosynostosis syndromes.

Objective: Patients with craniosynostosis syndromes are at risk of increased intracranial pressure (ICP) and Chiari I malformation (CMI), caused by a combination of restricted skull growth, venous hypertension, obstructive sleep apnea (OSA), and an overproduction or insufficient resorption of cerebrospinal fluid. This study evaluates whether craniosynostosis patients with CMI have an imbalance between cerebellar volume (CV) and posterior fossa volume (PFV), that is, an overcrowded posterior fossa.

Methods: Volumes were measured in 3D-SPGR T1-weighted MR scans of 28 'not-operated' craniosynostosis patients (mean age: 4.