{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,14]],"date-time":"2025-11-14T07:37:52Z","timestamp":1763105872919,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2022,7,15]],"date-time":"2022-07-15T00:00:00Z","timestamp":1657843200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002347","name":"BMBF RESPONSE FKZ","doi-asserted-by":"publisher","award":["03ZZ0922E","03ZZ0922B"],"award-info":[{"award-number":["03ZZ0922E","03ZZ0922B"]}],"id":[{"id":"10.13039\/501100002347","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>Otitis media is often connected to Eustachian tube dysfunction (ETD). Until now, there was no large animal model available for the examination of new treatment methods such as stents for the Eustachian tube (ET). Thus, the aim of the study was to develop a method to reproducibly induce ETD by injection of fillers and without permanent closure of the ET. Tools for safe injection of hyaluronic acid (HA) in the surrounding of the ET were developed. In ex vivo experiments, HA mixed with Imeron\u00ae was injected close to the nasopharyngeal orifice of the ET of blackface sheep. The established depot was visualized using cone beam computer tomography and magnetic resonance imaging, and stents could be placed into the ET. A reliable position of the HA depot was achieved. This method was transferred to in vivo, and middle ear ventilation was investigated by tympanometry. ETD was achieved with amounts of 2.5 mL HA or higher. None of the animals showed any sign of discomfort or complications. The induced ETD lasted for 3 to 13 (maximum observation period) weeks and was also combined with middle ear effusion. A model of ETD based on injection of HA next to the ET was successfully established and is now available to test novel treatment options for ET functionality.<\/jats:p>","DOI":"10.3390\/bioengineering9070317","type":"journal-article","created":{"date-parts":[[2022,7,15]],"date-time":"2022-07-15T00:17:10Z","timestamp":1657844230000},"page":"317","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Development of an In Vivo Model for Eustachian Tube Dysfunction"],"prefix":"10.3390","volume":"9","author":[{"given":"Niels","family":"Oppel","sequence":"first","affiliation":[{"name":"Department of Otorhinolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Malena","family":"Ezzat","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Philipp","family":"Kr\u00fcger","sequence":"additional","affiliation":[{"name":"bess pro GmbH, Gustav-Krone-Str. 7, 14167 Berlin, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-7259-3349","authenticated-orcid":false,"given":"Katharina","family":"Schmitt","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexandra","family":"Napp","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Friederike","family":"Pohl","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3438-0254","authenticated-orcid":false,"given":"Andre","family":"Bleich","sequence":"additional","affiliation":[{"name":"Institute for Laboratory Animal Science and Central Animal Facility, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9307-5989","authenticated-orcid":false,"given":"Thomas","family":"Lenarz","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany"},{"name":"Cluster of Excellence Hearing4all, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tobias","family":"Stein","sequence":"additional","affiliation":[{"name":"bess pro GmbH, Gustav-Krone-Str. 7, 14167 Berlin, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gerrit","family":"Paasche","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany"},{"name":"Cluster of Excellence Hearing4all, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7596-4566","authenticated-orcid":false,"given":"Robert","family":"Schuon","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"170","DOI":"10.1288\/00005537-189809000-00015","article-title":"Diseases of the Middle Ear","volume":"5","author":"Lapsley","year":"1898","journal-title":"Laryngoscope"},{"key":"ref_2","unstructured":"Snow, J.B., and Ballenger, J.J. 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