{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T05:37:47Z","timestamp":1770788267912,"version":"3.50.0"},"reference-count":56,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,4,13]],"date-time":"2025-04-13T00:00:00Z","timestamp":1744502400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100007569","name":"Carl-Zeiss-Stiftung \u201cBreakthroughs at Universities 2020: Intelligent Solutions for an Aging Society\u201d","doi-asserted-by":"publisher","award":["P2019-01-001"],"award-info":[{"award-number":["P2019-01-001"]}],"id":[{"id":"10.13039\/100007569","id-type":"DOI","asserted-by":"publisher"}]},{"name":"University of Tuebingen, the Faculty of Medicine of the University of Tuebingen, and the Center for Ophthalmology at the University of Tuebingen","award":["P2019-01-001"],"award-info":[{"award-number":["P2019-01-001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>The measurement of electrical potentials in the human body is becoming increasingly important in healthcare as a valuable diagnostic parameter. In ophthalmology, while these signals are primarily used to assess retinal function, other applications, such as recording accommodation-related biopotentials from the ciliary muscle, remain poorly understood. Here, we present the development and evaluation of a novel implantable ring electrode for recording biopotentials from the ciliary muscle. Inspired by capsular tension rings, the electrode was fabricated using laser cutting, wiring, and physical vapor deposition coating. The constant impedance and weight over a simulated aging period of 391 days, demonstrated the electrode\u2019s stability. In vivo testing in non-human primates further validated the electrode\u2019s surgical handling and long-term stability, with no delamination or tissue ingrowth after 100 days of implantation. Recorded biopotentials from the ciliary muscle (up to 700 \u00b5V) exceeded amplitudes reported in the literature. While the results are promising, further research is needed to investigate the signal quality and origin as well as the correlation between these signals and ciliary muscle activity. Ultimately, this electrode will be used in an implanted device to record ciliary muscle biopotentials to control an artificial lens designed to restore accommodation in individuals with presbyopia.<\/jats:p>","DOI":"10.3390\/bios15040247","type":"journal-article","created":{"date-parts":[[2025,4,14]],"date-time":"2025-04-14T04:42:07Z","timestamp":1744605727000},"page":"247","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Design and In Vivo Evaluation of an Intraocular Electrode for Ciliary Muscle Biopotential Measurement in a Non-Human Primate Model of Human Accommodation"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-6029-5280","authenticated-orcid":false,"given":"Sven","family":"Schumayer","sequence":"first","affiliation":[{"name":"Faculty Mechanical and Medical Engineering (MME), Institute for Microsystems Technology (iMST), Furtwangen University, 78120 Furtwangen, Germany"},{"name":"Institute for Ophthalmic Research, University of Tuebingen, 72076 Tuebingen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Esmaeil Ghadiri","family":"Zahrani","sequence":"additional","affiliation":[{"name":"Institute for Advanced Manufacturing (KSF), Furtwangen University, 78532 Tuttlingen, Germany"},{"name":"Department of Microsystems Engineering (IMTEK), University of Freiburg, 79110 Freiburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4393-4500","authenticated-orcid":false,"given":"Bahman","family":"Azarhoushang","sequence":"additional","affiliation":[{"name":"Institute for Advanced Manufacturing (KSF), Furtwangen University, 78532 Tuttlingen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Volker","family":"Bucher","sequence":"additional","affiliation":[{"name":"Faculty Mechanical and Medical Engineering (MME), Institute for Microsystems Technology (iMST), Furtwangen University, 78120 Furtwangen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7725-7961","authenticated-orcid":false,"given":"Torsten","family":"Stra\u00dfer","sequence":"additional","affiliation":[{"name":"Institute for Ophthalmic Research, University of Tuebingen, 72076 Tuebingen, Germany"},{"name":"University Eye Hospital Tuebingen, 72076 Tuebingen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"14383","DOI":"10.3402\/jchimp.v2i1.14383","article-title":"A Brief Review: History to Understand Fundamentals of Electrocardiography","volume":"2","author":"AlGhatrif","year":"2012","journal-title":"J. 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