CSF flowmetry: an innovative technique in diagnosing normal pressure hydrocephalus
Keywords:CSF flowmetry, Hydrocephalus, NPH, Phase contrast MRI
Background: Normal pressure hydrocephalus is a very gloomy entity. The objective of this study is to analyse aqueductal velocity parameters by phase contrast MRI CSF flowmetry in Idiopathic Normal pressure hydrocephalus patients (NPH).
Methods: This study consists of 72 participants which included 36 patients and 36 matched healthy controls. The study stretched over three years in multicentre tertiary research hospitals using 3T MRI scanner. Both normal MRI sequences and phase contrast CSF flowmetry was done for both group of patients and result analysed using SPSS 17 software.
Results: Mean age of patients in our study is 61.07 years. The most common clinical symptom was gait unsteadiness in our study. Most common conventional MRI finding was ventriculomegaly with transependymal seepage of CSF. Amongst CSF flowmetry parameters Aqueductal stroke volume, peak systolic velocity, mean systolic velocity, forward flow volume and backward flow volume were statistically significant in differentiating cases from controls.
Conclusions: MRI CSF flowmetry using phase contrast method is an advanced imaging parameter which can non-invasively and reliably detect NPH. Also, it can be used to follow the response to treatment following shunting and can act as a prognostic marker.
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