AUTHOR=Giannini Giulia , Jusue-Torres Ignacio , Mantovani Paolo , Mazza Liliana , Pirina Alessandro , Valsecchi Nicola , Milletti David , Albini-Riccioli Luca , Cevoli Sabina , Yasar Sevil , Palandri Giorgio 

TITLE=INPH and parkinsonism: A positive shunt response with a negative tap test

JOURNAL=Frontiers in Neurology

VOLUME=Volume 14 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2023.1150258

DOI=10.3389/fneur.2023.1150258

ISSN=1664-2295

ABSTRACT=Introduction
The aim of this study was to compare clinical and functional performances of INPH patients with and without Parkinsonism at initial evaluation, 72 hours after cerebrospinal fluid tap test (CSF TT) and six months after ventriculoperitoneal shunt (VPS) surgery. 

Materials and Methods 
This is an observational prospective study on INPH patients who underwent VPS. Patients were classified in INPH with (INPH-P+) and without parkinsonism (INPH-P-). We used time up and go (TUG), Tinetti performance oriented mobility assessment (POMA), INPH grading scale (INHPGS) and modified rankin scale (mRS) at baseline, 72 hours after CSF TT and six months after VPS surgery. 

Results
64 patients with probable INPH were included, 12 patients INPH-P+ and 52 controls INPH-P-. INPH patients showed significant improvement in all clinical and neurological parameters after VPS including TUG, Tinetti POMA, INPHGS and mRS (p<0.001) with the exception of mRS where there was no significant change 72h after CSF TT compared to baseline for INPH patients (p=0.182). INPH-P+ patients performed significantly worse when compared to INPH-P- patients on Tinetti POMA and mRS at baseline, at 72h post CSF TT and at 6 months post VPS with INPHGS worst at 72h post CSF TT. There was no difference between INPH-P+ and INPH-P- patients for TUG at baseline (p=0.270), at 72h post CSF TT (p=0.487) and at 6 months post VPS (p=0.182). INPH-P+ patients did not changes in any of the parameters at 72h post CSF TT compared to baseline, however, there was a trend towards improvement on TUG (p=0.058), Tinetti Gait (p=0.062) and Tinetti Total (p=0.067). INPH-P+ significantly improved in all parameters 6 months post VPS compared to baseline except for mRS (p=0.124). INPH-P- patients significantly improved in all parameters at 72h post CSF TT and at 6 months post VPS compared to baseline respectively, except on mRS 72h after CSF TT (p=0.299).

Conclusions
Patients with INPH and parkinsonism overall do worse than patients without parkinsonism. Unsatisfying response to CSF tap test in INPH patients with parkinsonism should not be used as an exclusion criterion from VPS surgery, since patients with and without parkinsonism showed significant improvement post VPS.