Evidence map›Paper›PMID 41612456›Full record

ArticleFluids and barriers of the CNS2026

Evaluation of shunt valve flow dynamics in series.

Gwendolyn L M Williams, Kenae Thompson, Michael Meggyesy, Dipankar Biswas, Ryan Lee, Sai Chandan Reddy, S Farzad Maroufi, Carolyn A Harris, Mark Luciano

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Article in Fluids and barriers of the CNS, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. An erratum has been issued. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

9 authors.

Gwendolyn L M WilliamsDepartment of Chemical Engineering and Materials Science, Wayne State University, Detroit, MI, USA. hq4570@wayne.edu.
Kenae ThompsonDepartment of Biomedical Engineering, Wayne State University, Detroit, MI, USA.
Michael MeggyesyDepartment of Neurosurgery, Cleveland Clinic, Cleveland, OH, USA.
Dipankar BiswasDepartment of Neurosurgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
Ryan LeeDepartment of Neurosurgery, School of Medicine, Vanderbilt University, Nashville, TN, USA.
Sai Chandan ReddyDepartment of Neurosurgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
S Farzad MaroufiDepartment of Neurosurgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
Carolyn A HarrisDepartment of Chemical Engineering and Materials Science, Wayne State University, Detroit, MI, USA.
Mark LucianoDepartment of Neurosurgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

background and purposeDysregulation of cerebrospinal fluid (CSF) volume results in hydrocephalus, a disease that leads to over 30,000 surgical shunt-valve implantations annually in the US. These shunt-valves require a trial-and-error process to determine optimal settings for each individual, sometimes resulting in implantation of multiple valves in series. This work sought to evaluate two mathematical models of the relationship between valve opening pressure settings in series and resultant drainage using a benchtop system to aid clinicians in determination of optimal shunt-valve settings.

methodsA gravity-driven in-vitro flow system at 37 °C with a simulated ICP of 22 cmH

resultsIn isolation, differential pressure and gravitational valves had low intra- and inter-valve variability (p > 0.05). Valves in series had highly variable flowrates across trials and sets of valves in both supine and upright positions (p < 0.05). Using calculated combined valve coefficients to predict flowrates of valves in series, the average percent error was 15 ± 7% and 23 ± 18% in the supine and upright positions, respectively.

conclusionsIn all, neither of the two models outperformed the other and both were insufficient to properly characterize the relationship between drainage and opening pressures of valves in series. These results indicate low flowrate variability of isolated valves but high variability of valves placed in series. Without a consistent model from which opening pressure setting of valves in series can be determined, physicians must rely on a trial-and-error method in optimal opening pressure determination which directly impacts patient outcomes. These findings underscore the difficulties faced by physicians in determination of optimal valve settings for shunted patients.

Indexed as

Cerebrospinal Fluid ShuntsHydrocephalusHydrodynamicsModels, TheoreticalHumansCerebrospinal fluidCerebrospinal fluid dynamicsDifferential pressure valveGravitational valveHydrocephalusIntracranial pressureShunt-valves

Identifiers

PMID41612456
PMCPMC12857078

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.