TY - JOUR

T1 - Prediction of shunt response in idiopathic normal pressure hydrocephalus by combined lumbar infusion test and preoperative imaging scoring

AU - Hasselbalch, Steen Gregers

AU - Carlsen, Jonathan Frederik

AU - Alaouie, Mohamed Moussa

AU - Munch, Tina Nørgaard

AU - Holst, Anders Vedel

AU - Taudorf, Sarah

AU - Rørvig-Løppentien, Christina

AU - Juhler, Marianne

AU - Waldemar, Gunhild

N1 - Publisher Copyright: © 2023 The Authors. European Journal of Neurology published by John Wiley & Sons Ltd on behalf of European Academy of Neurology.

PY - 2023

Y1 - 2023

N2 - Background and purpose: Idiopathic normal pressure hydrocephalus (iNPH) is a potentially treatable disorder, but prognostic tests or biomarkers are lacking. The aim was to study the predictive power of clinical, neuroimaging and lumbar infusion test parameters (resistance to outflow Rout, cardiac-related pulse amplitude PA and the PA to intracranial pressure ICP ratio). Methods: In all, 127 patients diagnosed with iNPH who had a lumbar infusion test, a subsequent ventriculo-peritoneal shunt operation and at least 2 months of postoperative follow-up were retrospectively included. Preoperative magnetic resonance images were visually scored for NPH features using the iNPH Radscale. Preoperative and postoperative assessment was performed using cognitive testing, as well as gait and incontinence scales. Results: At follow-up (7.4 months, range 2–20 months), an overall positive response was seen in 82% of the patients. Gait was more severely impaired at baseline in responders compared to non-responders. The iNPH Radscale score was borderline significantly higher in responders compared with non-responders, whereas no significant differences in infusion test parameters were seen between responders and non-responders. Infusion test parameters performed modestly with high positive (75%–92%) but low negative (17%–23%) predictive values. Although not significant, PA and PA/ICP seemed to perform better than Rout, and the odds ratio for shunt response seemed to increase in patients with higher PA/ICP, especially in patients with lower iNPH Radscale scores. Conclusion: Although only indicative, lumbar infusion test results increased the likelihood of a positive shunt outcome. Pulse amplitude measures showed promising results that should be further explored in prospective studies.

AB - Background and purpose: Idiopathic normal pressure hydrocephalus (iNPH) is a potentially treatable disorder, but prognostic tests or biomarkers are lacking. The aim was to study the predictive power of clinical, neuroimaging and lumbar infusion test parameters (resistance to outflow Rout, cardiac-related pulse amplitude PA and the PA to intracranial pressure ICP ratio). Methods: In all, 127 patients diagnosed with iNPH who had a lumbar infusion test, a subsequent ventriculo-peritoneal shunt operation and at least 2 months of postoperative follow-up were retrospectively included. Preoperative magnetic resonance images were visually scored for NPH features using the iNPH Radscale. Preoperative and postoperative assessment was performed using cognitive testing, as well as gait and incontinence scales. Results: At follow-up (7.4 months, range 2–20 months), an overall positive response was seen in 82% of the patients. Gait was more severely impaired at baseline in responders compared to non-responders. The iNPH Radscale score was borderline significantly higher in responders compared with non-responders, whereas no significant differences in infusion test parameters were seen between responders and non-responders. Infusion test parameters performed modestly with high positive (75%–92%) but low negative (17%–23%) predictive values. Although not significant, PA and PA/ICP seemed to perform better than Rout, and the odds ratio for shunt response seemed to increase in patients with higher PA/ICP, especially in patients with lower iNPH Radscale scores. Conclusion: Although only indicative, lumbar infusion test results increased the likelihood of a positive shunt outcome. Pulse amplitude measures showed promising results that should be further explored in prospective studies.

KW - imaging

KW - infusion test

KW - normal pressure hydrocephalus

KW - prediction

KW - prognostic factors

KW - ventriculo-peritoneal shunt

U2 - 10.1111/ene.15981

DO - 10.1111/ene.15981

M3 - Journal article

C2 - 37433569

AN - SCOPUS:85165511001

VL - 30

SP - 3047

EP - 3055

JO - European Journal of Neurology

JF - European Journal of Neurology

SN - 1351-5101

IS - 10

ER -