{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,5]],"date-time":"2026-11-05T00:15:04Z","timestamp":1793837704378,"version":"4.6.1"},"reference-count":19,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2024,9,3]],"date-time":"2024-09-03T00:00:00Z","timestamp":1725321600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2024,9,3]],"date-time":"2024-09-03T00:00:00Z","timestamp":1725321600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["BMC Ophthalmol"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Regional anaesthesia education, especially for ocular procedures, necessitates reliable surgical training models. While cadaveric models offer anatomical fidelity, conventional embalming methods may compromise tissue integrity. We aimed to assess the effectiveness of Thiel cadavers for training in sub-Tenon\u2019s blocks by evaluating ocular tissues and measuring insertion forces.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Experimental design, using twenty eyes from ten Thiel cadaver heads. These cadavers were specifically prepared to test the administration of sub-Tenon\u2019s blocks. The research was conducted in a controlled laboratory setting appropriate for handling cadaveric materials and conducting precise measurements. Each cadaver eye underwent an initial ultrasound examination, and its axial length was noted. An intravitreal injection of heptastarch solution followed, to re-establish the eye\u2019s sphericity. After this volume injection, the axial length and intraocular pressure were measured again. Mock sub-Tenon\u2019s blocks were administered in 2 separate quadrants of the eye, with insertion forces measured using a pressure gauge. These were compared to a data set of insertion forces measured in a series of isolated pig\u2019s eyes on which STBs had been performed. Main outcome measurements were macroscopic assessment of the ocular tissue layers and the insertion forces required for the sub-Tenon\u2019s blocks. In a second set of 10 Thiel cadaver heads, 5 ml of sodium chloride were injected as sub-Tenon\u2019s blocks and the emergence of a periocular \u201cT-sign\u201d ascertained and measured by ultrasound.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Four of twenty eyes (20%) retained near-natural sphericity, with the remaining requiring volume injection to approximate physiological shape and pressure. The conjunctiva and Tenon\u2019s layer were intact, and correct cannula placement was achieved in all cases. In 16 of 20 eyes where T-signs could be measured, the median thickness of the T-sign amounted to 2.72\u00a0mm (range 1.34\u00a0mm\u20135.28\u00a0mm). The average maximum cannula insertion force was 2.92 Newtons. Insertion forces in intact Thiel cadaver heads were consistently higher than in isolated pig\u2019s eyes (3.6 N vs 2.0 N).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>These findings suggest that Thiel cadavers are a promising model for training in sub-Tenon\u2019sblocks, despite the challenge of often desiccated and involuted eyes.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1186\/s12886-024-03630-3","type":"journal-article","created":{"date-parts":[[2024,9,3]],"date-time":"2024-09-03T07:02:07Z","timestamp":1725346927000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Thiel cadaver eye as a training model for sub-Tenon\u2019s blocks: a feasibility study"],"prefix":"10.1186","volume":"24","author":[{"given":"Friedrich","family":"Lersch","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Damian","family":"Schnidrig","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Susanne","family":"Boemke","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Valentin","family":"Djonov","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Damian","family":"Jaggi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Florian M.","family":"Heussen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2024,9,3]]},"reference":[{"key":"3630_CR1","doi-asserted-by":"crossref","unstructured":"Kumar NJ, George B, Sivaprakasam M, Jaichandran VV. A mannequin-based training system with integrated sensors for ophthalmic sub-Tenon anesthesia. IEEE Sens J. 2021;21(3):3839\u201348.","DOI":"10.1109\/JSEN.2020.3025963"},{"issue":"5","key":"3630_CR2","doi-asserted-by":"publisher","first-page":"400","DOI":"10.1177\/0310057X211063892","volume":"50","author":"AWY Chua","year":"2022","unstructured":"Chua AWY, Chua MJ, Harrisberg BP, Kumar CM. Inexpensive home-assembled human skull model for training and learning the peribulbar block technique. Anaesth Intensive Care. 2022;50(5):400\u20132.","journal-title":"Anaesth Intensive Care"},{"key":"3630_CR3","unstructured":"Lersch F. Sub-Tenon\u2019s training model: cherry tomato-model. www.roah.ch; 2020. 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Donors provided formal consent for using their body parts post-mortem in research through signed donation forms filed by the Berne university institutional review board (Kantonale Ethikkommission f\u00fcr die Forschung, Bern). According to national legislation of 2009 and 2014 (cited above) ethical approval for this study was not required as it did not involve living patients.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare no competing interests.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"391"}}