{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T05:10:55Z","timestamp":1778217055046,"version":"3.51.4"},"reference-count":35,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T00:00:00Z","timestamp":1778198400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Bioeng. Biotechnol."],"abstract":"\n Objective<\/jats:title>\n \n This study aimed to systematically compare the enhancing effects of different UVA irradiation intensities on the biomechanical properties of\n ex vivo<\/jats:italic>\n porcine cornea and sclera, to clarify the differences in the \u201cdose-response\u201d relationships between the two tissues during cross-linking, and to provide a parametric basis for extending cross-linking technology to the treatment of scleral diseases such as pathological myopia.\n <\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n \n Eighty fresh\n ex vivo<\/jats:italic>\n porcine eyes were used. The cornea and sclera were each randomly divided into 4 groups according to irradiation intensity: a control group (no irradiation), and experimental groups treated at 3,15and 30\u00a0mW\/cm\n 2<\/jats:sup>\n (total energy 5.4\u00a0J\/cm\n 2<\/jats:sup>\n ). Following infiltration with a 0.1% riboflavin solution, irradiation was performed with 370\u00a0nm UVA light, the procedure was assisted by pure oxygen blowing. Key parameters extracted included the secant modulus (at 2%, 6%, and 10% strain points), the tangent modulus (slope of the linear elastic region), and the Yeoh hyperelastic model parameters (C\n 1<\/jats:sub>\n , C\n 2<\/jats:sub>\n ).\n <\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n In the cornea, both the secant modulus and tangent modulus showed a increase with rising irradiation intensity, with the 30\u00a0mW\/cm\n 2<\/jats:sup>\n group exhibiting the greatest enhancement magnitude (approximately a 146.2% increase in secant modulus at 10% strain). For the sclera, the modulus enhancement displayed a non-linear relationship, the 15\u00a0mW\/cm\n 2<\/jats:sup>\n group showed the optimal reinforcement effect (approximately a 176.13% increase in secant modulus), while the effect diminished in the 30\u00a0mW\/cm\n 2<\/jats:sup>\n group. Analysis of model parameters indicated that the increase in C\n 2<\/jats:sub>\n (governing nonlinear stiffening) after cross-linking was far greater than that in C\n 1<\/jats:sub>\n (governing initial stiffness), suggesting that cross-linking primarily enhances the tissue\u2019s resistance under large deformations. Inter-group comparisons revealed that under identical parameters at low to medium intensities (3 and 15\u00a0mW\/cm\n 2<\/jats:sup>\n ), the sclera exhibited a higher modulus increase rate than the cornea; at high intensity (30\u00a0mW\/cm\n 2<\/jats:sup>\n ), the cornea showed more significant enhancement.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusion<\/jats:title>\n \n The responses of the cornea and sclera to cross-linking intensity are fundamentally different: the reinforcement effect in the cornea increases with intensity, whereas the sclera has an optimal intensity (15\u00a0mW\/cm\n 2<\/jats:sup>\n ), beyond which further intensity increase leads to diminishing returns.\n <\/jats:p>\n <\/jats:sec>","DOI":"10.3389\/fbioe.2026.1799822","type":"journal-article","created":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T04:43:53Z","timestamp":1778215433000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Differential dose-response relationships of collagen cross-linking in the cornea and sclera"],"prefix":"10.3389","volume":"14","author":[{"given":"Haiyan","family":"Wang","sequence":"first","affiliation":[{"name":"Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital","place":["Tianjin, China"]},{"name":"Department of Ophthalmology, Shijiazhuang People\u2019s Hospital","place":["Shijiazhuang, Hebei, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yanan","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Shijiazhuang People\u2019s Hospital","place":["Shijiazhuang, Hebei, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lingjuan","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Shijiazhuang People\u2019s Hospital","place":["Shijiazhuang, Hebei, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mingqi","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Shijiazhuang People\u2019s Hospital","place":["Shijiazhuang, Hebei, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiongwei","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, Shijiazhuang People\u2019s Hospital","place":["Shijiazhuang, Hebei, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ruibo","family":"Yang","sequence":"additional","affiliation":[{"name":"Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital","place":["Tianjin, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,5,8]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"10","DOI":"10.1167\/tvst.10.5.10","article-title":"High-fluence accelerated epithelium-off corneal cross-linking protocol provides dresden protocol-like corneal strengthening","volume":"10","author":"Abrishamchi","year":"2021","journal-title":"Transl. 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