{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T20:19:02Z","timestamp":1777580342572,"version":"3.51.4"},"reference-count":30,"publisher":"SAGE Publications","issue":"2","license":[{"start":{"date-parts":[[2025,9,2]],"date-time":"2025-09-02T00:00:00Z","timestamp":1756771200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["European Journal of Ophthalmology"],"published-print":{"date-parts":[[2026,3]]},"abstract":"<jats:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>This study evaluated the safety and effectiveness of two models of intrastromal corneal ring segments (ICRS)\u2014symmetric (uniform thickness and base width) and asymmetric (progressive thickness and base width)\u2014for the treatment of oval phenotype keratoconus.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A prospective, randomized, controlled clinical study was conducted on 64 eyes from 47 patients, divided into two groups: Group 1 (33 eyes) received symmetric ICRS, and Group 2 (31 eyes) received asymmetric ICRS. Comprehensive ophthalmic evaluations, including visual acuity, corneal topography, tomography, and aberrometry, were performed preoperatively and at 1, 3, 6, and 12 months postoperatively.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>At 12 months, Group 2 demonstrated significantly greater reductions in K1, Km, Kmax, asphericity, vertical coma and spherical aberration, and most topographic indices compared to Group 1. Best-corrected visual acuity was higher in Group 2, reaching statistical significance at 6 months. No implant-related complications were observed in either group.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Asymmetric ICRS provided superior topographic, tomographic, and aberrometric outcomes compared to symmetric ICRS in the treatment of asymmetric keratoconus, leading to greater improvements in corneal regularity, asphericity, and cone inclination.<\/jats:p>\n                    <jats:p>\n                      <jats:bold>Clinical Trial Registration:<\/jats:bold>\n                      This study was registered with the National Research Ethics Commission (CONEP) under registration number 32212020.9.0000.5505.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1177\/11206721251372378","type":"journal-article","created":{"date-parts":[[2025,9,2]],"date-time":"2025-09-02T12:24:08Z","timestamp":1756815848000},"page":"211-223","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":0,"title":["A randomized controlled trial of symmetric versus asymmetric intrastromal corneal ring segments for asymmetric keratoconus"],"prefix":"10.1177","volume":"36","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7375-9964","authenticated-orcid":false,"given":"Belquiz Amaral","family":"Nassaralla","sequence":"first","affiliation":[{"name":"Instituto de Olhos de Goi\u00e2nia"},{"name":"Department of Ophthalmology and Visual Sciences, Escola Paulista de Medicina, Universidade Federal de S\u00e3o Paulo, S\u00e3o Paulo, SP, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6990-9798","authenticated-orcid":false,"given":"Jordana Sandes Barbosa","family":"Soares","sequence":"additional","affiliation":[{"name":"Universidade Federal de Goi\u00e1s"},{"name":"N\u00facleo de Medicina Ocular, Goi\u00e2nia, GO, Brazil"},{"name":"Bueno Medical Center Oftalmologia, Goi\u00e2nia, GO, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9448-8742","authenticated-orcid":false,"given":"Mauro","family":"Campos","sequence":"additional","affiliation":[{"name":"Universidade Federal de S\u00e3o Paulo"},{"name":"PEnsE, Research, Teaching and Experimentation, Vision One, S\u00e3o Paulo, SP, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"179","published-online":{"date-parts":[[2025,9,2]]},"reference":[{"key":"e_1_3_2_2_2","doi-asserted-by":"publisher","DOI":"10.1167\/tvst.8.3.38"},{"key":"e_1_3_2_3_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0886-3350(02)01495-5"},{"key":"e_1_3_2_4_2","doi-asserted-by":"publisher","DOI":"10.5005\/jp-journals-10025-1132"},{"key":"e_1_3_2_5_2","doi-asserted-by":"publisher","DOI":"10.3928\/1081597X-20131217-02"},{"key":"e_1_3_2_6_2","doi-asserted-by":"publisher","DOI":"10.1007\/978-3-030-85361-7_43"},{"key":"e_1_3_2_7_2","doi-asserted-by":"publisher","DOI":"10.3928\/1081597X-20161027-02"},{"key":"e_1_3_2_8_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1755-3768.2013.S053.x"},{"key":"e_1_3_2_9_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0886-3350(01)01172-5"},{"key":"e_1_3_2_10_2","doi-asserted-by":"publisher","DOI":"10.1097\/ICO.0000000000001075"},{"key":"e_1_3_2_11_2","doi-asserted-by":"publisher","DOI":"10.1097\/ICO.0000000000001449"},{"key":"e_1_3_2_12_2","doi-asserted-by":"publisher","DOI":"10.3928\/1081597X-20190916-01"},{"key":"e_1_3_2_13_2","first-page":"92","article-title":"The new Ferrara ring nomogram: the importance of corneal asphericity in ring selection","volume":"9","author":"Ferrara P","year":"2010","unstructured":"Ferrara P, Torquetti L. 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