Is there a link between ICP-derived infusion test parameters and outcome after shunting in normal pressure hydrocephalus?

Abstract

Objective: The term “hydrocephalus” encompasses a range of disorders characterised by clinical symptoms, abnormal brain imaging and derangement of cerebrospinal fluid (CSF) dynamics. The ability to elucidate which patients would benefit from CSF diversion (a shunt or third ventriculostomy) is often unclear. Similar difficulties are encountered in shunted patients to predict the scope for improvement by shunt re-adjustment or revision. Materials and methods: We compared retrospective pre-shunting infusion test results performed in 310 adult patients diagnosed with normal pressure hydrocephalus (NPH) and their improvement after shunting. Results: Resistance to CSF outflow correlated significantly with improvement (p < 0.05). Other markers known from the literature, such as amplitude in CSF pulse pressure, the slope of the amplitude–pressure regression line, or elasticity did not show any correlation with outcome. Conclusion: Outcome following shunting in adult NPH is associated with resistance to CSF outflow; however, the latter cannot be taken as an absolute predictor of shunt response.