{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,20]],"date-time":"2026-04-20T16:33:08Z","timestamp":1776702788334,"version":"3.51.2"},"reference-count":33,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2021,10,2]],"date-time":"2021-10-02T00:00:00Z","timestamp":1633132800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100012331","name":"Agentschap Innoveren en Ondernemen","doi-asserted-by":"publisher","award":["HBC.2018.0184"],"award-info":[{"award-number":["HBC.2018.0184"]}],"id":[{"id":"10.13039\/100012331","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003130","name":"Fonds Wetenschappelijk Onderzoek","doi-asserted-by":"publisher","award":["1804816N"],"award-info":[{"award-number":["1804816N"]}],"id":[{"id":"10.13039\/501100003130","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Making use of magnetic resonance imaging (MRI) for diagnostics on patients with implanted medical devices requires caution due to mutual interactions between the device and the electromagnetic fields used by the scanner that can cause a number of adverse events. The presented study offers a novel test method to quantify the risk of unintended output of acoustically stimulating hearing implants. The design and operating principle of an all-optical, MRI safe vibrometer is outlined, followed by an experimental verification of a prototype. Results obtained in an MRI environment indicate that the system can detect peak displacements down to 8 pm for audible frequencies. Feasibility testing was performed with an active middle ear implant that was exposed to several pulse sequences in a 1.5 Tesla MRI environment. Magnetic field induced actuator vibrations, measured during scanning, turned out to be equivalent to estimated sound pressure levels between 25 and 85 dB SPL, depending on the signal frequency. These sound pressure levels are situated well below ambient sound pressure levels generated by the MRI scanning process. The presented case study therefore indicates a limited risk of audible unintended output for the examined hearing implant during MRI.<\/jats:p>","DOI":"10.3390\/s21196589","type":"journal-article","created":{"date-parts":[[2021,10,10]],"date-time":"2021-10-10T21:37:49Z","timestamp":1633901869000},"page":"6589","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["A Miniature, Fiber-Optic Vibrometer for Measuring Unintended Acoustic Output of Active Hearing Implants during Magnetic Resonance Imaging"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0606-0103","authenticated-orcid":false,"given":"Guy","family":"Fierens","sequence":"first","affiliation":[{"name":"Laboratory of Soft Matter and Biophysics, Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200D, B-3001 Heverlee, Belgium"},{"name":"Cochlear Technology Centre, Schali\u00ebnhoevedreef 20I, B-2800 Mechelen, Belgium"},{"name":"Research Group Experimental Otorhinolaryngology, Department of Neurosciences, KU Leuven, Herestraat 49, B-3000 Leuven, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Joris","family":"Walraevens","sequence":"additional","affiliation":[{"name":"Cochlear Technology Centre, Schali\u00ebnhoevedreef 20I, B-2800 Mechelen, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7055-4039","authenticated-orcid":false,"given":"Ronald","family":"Peeters","sequence":"additional","affiliation":[{"name":"Department of Radiology, University Hospitals Leuven, Herestraat 49, B-3000 Leuven, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3512-1334","authenticated-orcid":false,"given":"Nicolas","family":"Verhaert","sequence":"additional","affiliation":[{"name":"Research Group Experimental Otorhinolaryngology, Department of Neurosciences, KU Leuven, Herestraat 49, B-3000 Leuven, Belgium"},{"name":"Department of Otorhinolaryngology, University Hospitals Leuven, Herestraat 49, B-3000 Leuven, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7740-5215","authenticated-orcid":false,"given":"Christ","family":"Glorieux","sequence":"additional","affiliation":[{"name":"Laboratory of Soft Matter and Biophysics, Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200D, B-3001 Heverlee, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"294","DOI":"10.1016\/j.burns.2007.11.008","article-title":"MRI induced fourth-degree burn in an extremity, leading to amputation","volume":"35","author":"Haik","year":"2009","journal-title":"Burns"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"457","DOI":"10.1053\/crad.2000.0688","article-title":"Thermal injuries associated with MRI","volume":"56","author":"Dempsey","year":"2001","journal-title":"Clin. 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