Posterior Fossa Volume Relates To The Pathogenesis Of Chiari Malformation Type â…  And The Treatment Response

ObjectivesThe aim of this paper was to analyze the posterior fossa volume’s (PFV) correlations with the pathogenesis of Chiari malformation Type I (CMI) as well as the treatment response.MethodsA retrospective study was performed on patients with CMI from December2011to June2013in our hospital, and the inclusion criteria were as followings:(1) the diagnosis of CMI in each patient confirmed by combined head, cervical spine MRI, with or without syringomyelia;(2) all patients had indications for operation with significant clinical features;(3) all patients underwent a posterior fossa decompression (PFD);(4) followed up for3month to2year. And matched healthy adults were recruited as control. The degree of PFV in CMI was compared with the control group. Then a further analysis was performed to determine the association between the posterior fossa volume in CMI patients and the severity of cerebellar tonsillar displacement as well as the surgical treatment response.ResultsSignificant differences were found in CMI patients compared with the control group. CMI patients with tonsillar descend of different degrees were found to have no significant difference. A statistically significant correlation was found between PFVand the treatment response.ConclusionsThe bony components of posterior fossa are malformed in CMI patients, which maybe the main cause of tonsillar descent. Surgical treatment response is significantly influenced by the degree of PFV.