The goal of the proposed study is to assess the utility of novel, MR-based hydrodynamic measures of spinal canal resistance and compliance by showing differences: (1) between adult patients diagnosed with Chiari Malformation (CM) and healthy, age/gender-matched volunteers; and (2) within the CM patient group before and after surgical treatment.
We hypothesize that hydrodynamic changes to the CSF system, specifically longitudinal impedance, pulse wave velocity, and volumetric expansion, may better reflect the underlying pathophysiology associated with CM disease, and serve as a better prognostic indicator than standard static methods that are currently being used clinically.
Alterations to the hydrodynamics of CSF into, and out of, the cranium can be due, in part to structural anomalies leading to increased flow resistance or changes in spinal canal compliance, or both. The present study will employ non-invasive MR methods to standard clinical care for CM to determine the relationship between CSF dynamic measurements and static (i.e., anatomical/structural) measurements of tonsillar herniation, posterior fossa volume, and syrinx size (extent and width).
This work will serve as a pilot study for larger clinical studies to determine if an improved diagnosis of CM can be obtained from the assessment of CSF resistance and compliance, and whether this method may be useful in follow-up treatments. Future clinical studies would be required to determine the underlying causal relationship between these hydrodynamic parameters and neurological symptoms, radiological severity, and surgical success.
The significance of the current study will be to demonstrate the importance of CSF hydrodynamics in CM patients. As such, a new and more accurate method to assist in standard clinical diagnosis and treatment of CM may be possible which is important for the more 20,000 patients who are evaluated each year for decompression surgery.