{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,31]],"date-time":"2026-10-31T00:34:31Z","timestamp":1793406871065,"version":"4.5.0"},"reference-count":35,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,2,14]],"date-time":"2025-02-14T00:00:00Z","timestamp":1739491200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background\/Objectives: The evaluation of the differences in corneal epithelial thickness profiles in healthy eyes and eyes with mild and moderate stages of keratoconus, using optical coherence tomography (OCT). Methods: Fifty-two healthy eyes (group 0), forty-one eyes with mild keratoconus (group I), and thirty eyes with moderate keratoconus (group II) were included in this study. Only one of the patient\u2019s eyes was enrolled, and they were divided into groups using the Amsler\u2013Krumeich (A\u2013K) classification\u2014stage I and II. All patients underwent a visual acuity assessment, slit-lamp examination, corneal tomography, and automatic mapping of corneal thickness and epithelial thickness on a diameter of 9 mm. Corneal tomography with a Placido\/Scheimpflug instrument (Sirius, CSO, Florence, Italy) and OCT with a corneal adaptor module (Avanti RTVue XR, Optovue, Lombard, IL, USA) were used. Results: Minimum corneal epithelium thickness was 49.5, 43, and 40 \u00b5m in groups 0, I, and II, respectively (Kruskal\u2013Wallis test, p &lt; 0.001). A moderate correlation was found between minimum epithelial thickness and the apex curvature (Pearsons\u2019s coefficient r = \u22120.62, p &lt; 0.001) and posterior radius of central corneal curvature (Pearsons\u2019s coefficient r = 0.62, p &lt; 0.001). The difference between minimum and maximum epithelial thickness showed a high correlation (r = \u22120.770, p &lt; 0.001). In groups I and II, on corneal epithelial thickness maps the thinnest sector, located inferiorly and temporally to the center, was surrounded by sectors with increased thickness. Conclusions: At the apex of the cone, the corneal epithelium becomes thinner, and a thicker ring forms around the cone. Although there is a moderate-to-strong correlation to parameters linked with the severity of keratoconus, and minimum epithelial thickness as well as the minimum\u2013maximum difference, it is not possible to establish cut-off values for stages I and II in the Amsler\u2013Krumeich (A\u2013K) classification.<\/jats:p>","DOI":"10.3390\/jcm14041256","type":"journal-article","created":{"date-parts":[[2025,2,14]],"date-time":"2025-02-14T03:20:52Z","timestamp":1739503252000},"page":"1256","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Corneal Epithelial Thickness Maps in Eyes with Mild and Moderate Keratoconus"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2321-8411","authenticated-orcid":false,"given":"Patryk","family":"Mlyniuk","sequence":"first","affiliation":[{"name":"Department of Ophthalmology, Collegium Medicum, Nicolaus Copernicus University, ul. Ujejskiego 75, 85-168 Bydgoszcz, Poland"},{"name":"Oftalmika Eye Hospital, ul. Modrzewiowa 15, 85-631 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Magdalena","family":"Kaszuba-Modrzejewska","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Collegium Medicum, Nicolaus Copernicus University, ul. Ujejskiego 75, 85-168 Bydgoszcz, Poland"},{"name":"Oftalmika Eye Hospital, ul. Modrzewiowa 15, 85-631 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jagoda","family":"Rzeszewska-Zamiara","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Collegium Medicum, Nicolaus Copernicus University, ul. Ujejskiego 75, 85-168 Bydgoszcz, Poland"},{"name":"Oftalmika Eye Hospital, ul. Modrzewiowa 15, 85-631 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ilona","family":"Piotrowiak-Slupska","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Collegium Medicum, Nicolaus Copernicus University, ul. Ujejskiego 75, 85-168 Bydgoszcz, Poland"},{"name":"Oftalmika Eye Hospital, ul. Modrzewiowa 15, 85-631 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1332-3592","authenticated-orcid":false,"given":"Bartlomiej J.","family":"Kaluzny","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Collegium Medicum, Nicolaus Copernicus University, ul. Ujejskiego 75, 85-168 Bydgoszcz, Poland"},{"name":"Oftalmika Eye Hospital, ul. Modrzewiowa 15, 85-631 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,14]]},"reference":[{"key":"ref_1","unstructured":"Krachmer, J., Mannis, M., and Holland, E. (2010). Cornea, Mosby Elsevier. [3rd ed.]."},{"key":"ref_2","unstructured":"Trattler, W.B., Majmudar, P.A., Luchs, J.I., and Swartz, T.S. (2010). Cornea Handbook, SLACK Incorporated."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"190","DOI":"10.4103\/ijo.IJO_646_17","article-title":"Anatomy of cornea and ocular surface","volume":"66","author":"Sridhar","year":"2018","journal-title":"Indian J. Ophthalmol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"588","DOI":"10.1016\/j.jcrs.2010.12.037","article-title":"Anatomy and physiology of the cornea","volume":"37","author":"DelMonte","year":"2011","journal-title":"J. Cataract. Refract. 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