CSF FLOWMETRY USING PHASE-CONTRAST MRI FOR DIAGNOSIS OF NORMAL PRESSURE HYDROCEPHALUS AND PREDICTION OF SHUNT RESPONSE.

Abstract

Background: Differentiating NPH from cerebral atrophy due to other neurodegenerative diseases and normal aging remains a challenge. NPH- related dementia is the only surgically manageable dementia. Response to ventricular shunting in NPH is variable. This study aims to nd the CSF ow indices in NPH patients and their prognostic use in selection of shunt candidates. The study group consisted of 36 patients with NPHMethods: diagnoses and 10 asymptomatic age-matched controls. Quantitative assessment (peak systolic velocity and stroke volume) of CSF ow through the cerebral aqueduct using Phase-contrast MRI was done. Mean value ± SD of peak systolic velocity in controls was 5.5 ± 1.2 cm/s, while inResults: cases was 9.9 ± 3.5 cm/s. It was 10.9 ± 2.9 cm/s in shunt responders and 6.9 ± 2.0 cm/s in non-responders. Mean value ± SD of stroke volume in controls was 29.5 ± 3.2 μl, while in cases was 94.7 ± 60.5 μl. It was 115.2 ± 60.9 μl in shunt responders and 46.7 ± 17.1 μl in non-responders. Conclusion: Peak systolic velocity and stroke volume of CSF ow through the cerebral aqueduct are greater in NPH patients as compared to age- matched controls, and also greater in shunt-responsive NPH patients as compared to the non-responders. MRI CSF owmetry using phase-contrast method can act as a prognostic marker for shunt responsiveness.