{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,27]],"date-time":"2026-06-27T04:46:40Z","timestamp":1782535600305,"version":"3.54.5"},"reference-count":31,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T00:00:00Z","timestamp":1782086400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: Corneal collagen cross-linking (CXL) halts keratoconus progression, yet potential differences between conventional and accelerated protocols at one year remain uncertain. We analyzed the completed 12-month follow-up of a previously reported 6-month cohort to compare conventional (3 mW\/cm2 \u00d7 30 min; CXL 30) versus accelerated (9 mW\/cm2 \u00d7 10 min; CXL 10) CXL, interpreting outcomes within the ABCD framework alongside Kmax and curvature radii. Materials and Methods: In this single-center retrospective longitudinal analysis of prospectively collected routine clinical data, 22 eyes were included, with assessments performed at baseline and at 1, 3, 6, and 12 months of follow-up. Evaluated outcomes comprised ABCD stages (A\u2013D), anterior and posterior radius of curvature (ARC and PRC), Kmax, pachymetric and elevation indices, as well as UDVA and BCVA. Within-group change used Friedman with Wilcoxon post hoc; between-group differences used Mann\u2013Whitney (\u03b1 = 0.05). Results: Both protocols resulted in significant visual improvement and Kmax reduction at 12 months (overall time effect: CXL 30 p &lt; 0.001; CXL 10 p = 0.026). Median Kmax decreased 56.5 \u2192 52.3 D (CXL 30) and 59.3 \u2192 58.3 D (CXL 10). UDVA improved 0.2 \u2192 0.6 (CXL 30) and 0.2 \u2192 0.3 (CXL 10); BCVA 0.4 \u2192 0.8 (CXL 30) and 0.2 \u2192 0.5 (CXL 10). Tomographic analysis showed predominantly anterior changes, with a significant decrease in A stage in the CXL 30 group and an increase in ARC in both groups, more pronounced in CXL 30. In the late 6 \u2192 12-month window, posterior metrics (PRC and posterior elevation) were largely stable; raw PRC change did not reach significance. Conclusions: Conventional and accelerated CXL both stabilized keratoconus at one year with meaningful functional gains. Beyond 6 months, remodeling was predominantly anterior; within-group findings suggested a more pronounced anterior tomographic response in the CXL 30 group. The 12-month visit may be useful for reassessing stability after CXL, although this study was not designed to determine optimal retreatment timing or optical rehabilitation strategy. Longer-term studies with standardized biomechanical and densitometric endpoints are warranted to assess durability and refine protocol selection.<\/jats:p>","DOI":"10.3390\/medicina62061209","type":"journal-article","created":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T06:13:37Z","timestamp":1782195217000},"page":"1209","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["One-Year Comparative Outcomes of Conventional Versus Accelerated Corneal Cross-Linking in Progressive Keratoconus"],"prefix":"10.3390","volume":"62","author":[{"given":"Iva","family":"Be\u0161li\u0107","sequence":"first","affiliation":[{"name":"Department of Ophthalmology, University Hospital Centre Zagreb, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8229-7826","authenticated-orcid":false,"given":"Sania","family":"Vidas Pauk","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, University Hospital Centre Zagreb, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7535-3631","authenticated-orcid":false,"given":"Martina","family":"Tomi\u0107","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Vuk Vrhovac University Clinic for Diabetes, Endocrinology and Metabolic Diseases, Merkur University Hospital, Dugi dol 4a, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miro","family":"Kalauz","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, University Hospital Centre Zagreb, 10000 Zagreb, Croatia"},{"name":"School of Medicine, University of Zagreb, \u0160alata 3, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7137-5059","authenticated-orcid":false,"given":"Tomislav","family":"Kuzman","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, University Hospital Centre Zagreb, 10000 Zagreb, Croatia"},{"name":"School of Medicine, University of Zagreb, \u0160alata 3, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sonja","family":"Jandrokovi\u0107","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, University Hospital Centre Zagreb, 10000 Zagreb, Croatia"},{"name":"School of Medicine, University of Zagreb, \u0160alata 3, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2872-7351","authenticated-orcid":false,"given":"Ivan","family":"\u0160kegro","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, University Hospital Centre Zagreb, 10000 Zagreb, Croatia"},{"name":"School of Medicine, University of Zagreb, \u0160alata 3, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonela","family":"Geber","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, University Hospital Centre Zagreb, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lorena Karla","family":"\u0160klebar","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, University Hospital Centre Zagreb, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dina","family":"Le\u0161in Ga\u0107ina","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, University Hospital Centre Zagreb, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Petar","family":"Be\u0161li\u0107","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Clinical Hospital Sveti Duh, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sanja","family":"Masnec","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, University Hospital Centre Zagreb, 10000 Zagreb, Croatia"},{"name":"School of Medicine, University of Zagreb, \u0160alata 3, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1016\/S0039-6257(97)00119-7","article-title":"Keratoconus","volume":"42","author":"Rabinowitz","year":"1998","journal-title":"Surv. 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