Dynamic compliance of the CSF system in iNPH (Part I) - in vitro investigation of the impact of spinal canal stenoses

Dynamic compliance of the CSF system in iNPH (Part I) - in vitro investigation of the impact of spinal canal stenoses | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Dynamic compliance of the CSF system in iNPH (Part I) - in vitro investigation of the impact of spinal canal stenoses Anne E. Benninghaus, Kevin Ebers, Chuh-Hyoun Na, Hans Clusmann, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7376295/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 12 You are reading this latest preprint version Abstract Spinal canal stenosis is an age-related degenerative condition observed mainly in the cervical and lumbar regions. Recent research has suggested that such stenoses influence cerebrospinal fluid (CSF) dynamics in idiopathic normal pressure hydrocephalus (iNPH) patients by increasing spinal canal flow resistance thereby directly impacting craniospinal dynamic compliance and intracranial pressure (ICP). This study experimentally investigates the effects of cervical and lumbar spinal stenoses on CSF dynamics using a validated in vitro model. To simulate varying degrees of stenosis, controlled reductions in the spinal canal cross-sectional area were applied, and resulting changes in bidirectional cervical CSF flow, ICP, and compliance were measured. The results indicate that mild to moderate stenoses have minimal impact on CSF dynamics, whereas severe stenoses (cervical < 33 % and lum-bar < 17 % of initial cross sectional area) significantly alter CSF dynamics. These alterations were characterised by reduced dynamic compliance, decreased spinal CSF flow and increased ICP amplitudes up to 7.85 mmHg. These findings suggest that spinal stenoses critically alter key CSF dynamics, potentially contributing to iNPH. Further studies are required, especially on other influencing factors such as age-related changes in viscoelastic properties of the dural sac and the relevance of dynamic compliance of the CSF system, which will be addressed in Part II of this series. Spinal Canal Stenosis Compliance CSF Dynamics iNPH Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 22 Sep, 2025 Reviews received at journal 17 Sep, 2025 Reviews received at journal 17 Sep, 2025 Reviews received at journal 07 Sep, 2025 Reviewers agreed at journal 19 Aug, 2025 Reviewers agreed at journal 19 Aug, 2025 Reviewers agreed at journal 19 Aug, 2025 Reviewers agreed at journal 18 Aug, 2025 Reviewers invited by journal 18 Aug, 2025 Editor assigned by journal 16 Aug, 2025 Submission checks completed at journal 14 Aug, 2025 First submitted to journal 14 Aug, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7376295","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":502654447,"identity":"df1faa27-c588-4770-bae0-0c3a0247d7b0","order_by":0,"name":"Anne E. 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