Dynamic MRI and Quantitative MR CSF Flow Studies in Craniovertebral Junction Anomalies

Inclusion Criteria: * Healthy volunteers must be 18 yrs of age or older. * Patients w/Chiari 1 or CVJ malformations aged 12 yrs or older, * Able to cooperate in flexing and extending their neck within the cervical spine coil used for MR Imaging. * Pediatric patients will be included only if they can cooperate for additional sequences done for the study who don't require sedation or any form of anesthesia. Exclusion Criteria: * Patients who are medically unstable or cannot voluntarily flex or extend their necks. * Patients who have hardware in the head or necks which are incompatible with MR imaging. * Patient requiring any form of sedation which can lead to compromise of the airway with maneuvers described above. * History of prior head trauma or history of neurological conditions which can result in altered CSF dynamics.