{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,6]],"date-time":"2026-02-06T00:28:29Z","timestamp":1770337709846,"version":"3.49.0"},"reference-count":28,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2023,8,27]],"date-time":"2023-08-27T00:00:00Z","timestamp":1693094400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Commission Horizon 2020 research and innovation programme","award":["956720"],"award-info":[{"award-number":["956720"]}]},{"name":"European Commission Horizon 2020 research and innovation programme","award":["PZ00P2_174113"],"award-info":[{"award-number":["PZ00P2_174113"]}]},{"name":"Swiss National Science Foundation","award":["956720"],"award-info":[{"award-number":["956720"]}]},{"name":"Swiss National Science Foundation","award":["PZ00P2_174113"],"award-info":[{"award-number":["PZ00P2_174113"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>To build a representative 3D finite element model (FEM) for intracorneal ring segment (ICRS) implantation and to investigate localized optical changes induced by different ICRS geometries, a hyperelastic shell FEM was developed to compare the effect of symmetric and progressive asymmetric ICRS designs in a generic healthy and asymmetric keratoconic (KC) cornea. The resulting deformed geometry was assessed in terms of average curvature via a biconic fit, sagittal curvature (K), and optical aberrations via Zernike polynomials. The sagittal curvature map showed a locally restricted flattening interior to the ring (Kmax \u221211 to \u221225 dpt) and, in the KC cornea, an additional local steepening on the opposite half of the cornea (Kmax up to +1.9 dpt). Considering the optical aberrations present in the model of the KC cornea, the progressive ICRS corrected vertical coma (\u22123.42 vs. \u22123.13 \u00b5m); horizontal coma (\u22120.67 vs. 0.36 \u00b5m); and defocus (2.90 vs. 2.75 \u00b5m), oblique trefoil (\u22120.54 vs. \u22120.08 \u00b5m), and oblique secondary astigmatism (0.48 vs. \u22120.09 \u00b5m) aberrations stronger than the symmetric ICRS. Customized ICRS designs inspired by the underlying KC phenotype have the potential to achieve more tailored refractive corrections, particularly in asymmetric keratoconus patterns.<\/jats:p>","DOI":"10.3390\/bioengineering10091014","type":"journal-article","created":{"date-parts":[[2023,8,28]],"date-time":"2023-08-28T01:56:57Z","timestamp":1693187817000},"page":"1014","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Localized Refractive Changes Induced by Symmetric and Progressive Asymmetric Intracorneal Ring Segments Assessed with a 3D Finite-Element Model"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8169-8791","authenticated-orcid":false,"given":"Gonzalo","family":"Garc\u00eda de Oteyza","sequence":"first","affiliation":[{"name":"Cl\u00ednica Oftalmol\u00f3gica Garc\u00eda de Oteyza, 08017 Barcelona, Spain"},{"name":"Escuela de Doctorado, Universidad Aut\u00f3noma de Barcelona (UAB), 08193 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Juan","family":"\u00c1lvarez de Toledo","sequence":"additional","affiliation":[{"name":"Oftalvist Barcelona, 08017 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rafael I.","family":"Barraquer","sequence":"additional","affiliation":[{"name":"Centro de Oftalmolog\u00eda Barraquer, 08021 Barcelona, Spain"},{"name":"Universitat Internacional de Catalunya (UIC), 08017 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7202-7200","authenticated-orcid":false,"given":"Sabine","family":"Kling","sequence":"additional","affiliation":[{"name":"Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, 8092 Zurich, Switzerland"},{"name":"ARTORG Center for Biomedical Engineering Research, University of Bern, 3010 Bern, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"107","DOI":"10.1111\/cxo.12230","article-title":"Corneal biomechanics: A review","volume":"98","year":"2015","journal-title":"Clin. 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