{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T22:56:53Z","timestamp":1780959413116,"version":"3.54.1"},"reference-count":42,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2023,11,19]],"date-time":"2023-11-19T00:00:00Z","timestamp":1700352000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Life"],"abstract":"<jats:p>Purpose: Considering that peripheral corneal thinning occurs in keratoconus (KC), the anterior scleral thickness (AST) profile was measured to compare thickness variations in healthy and KC eyes across several meridians. Methods: This cross-sectional case\u2013control study comprised 111 eyes of 111 patients: 61 KC eyes and 50 age- and axial-length-matched healthy eyes. The AST was explored at three scleral eccentricities (1, 2, and 3 mm from the scleral spur) across four scleral zones (nasal, temporal, superior, and inferior) by using swept-source optical coherence tomography. The AST variations among eccentricities and scleral regions within and between groups were investigated. Results: The AST significantly varied with scleral eccentricity in healthy eyes over the temporal meridian (p = 0.009), whereas in KC eyes, this variation was observed over the nasal (p = 0.001), temporal (p = 0.029) and inferior (p = 0.006) meridians. The thinnest point in both groups was 2 mm posterior to the scleral spur (p &lt; 0.001). The sclera was thickest over the inferior region (control 581 \u00b1 52 \u03bcm, KC 577 \u00b1 67 \u03bcm) and thinnest over the superior region (control 448 \u00b1 48 \u03bcm, KC 468 \u00b1 58 \u03bcm) in both populations (p &lt; 0.001 for all eccentricities). The AST profiles were not significantly different between groups (p &gt; 0.05). The inferior\u2013superior thickness asymmetry was statistically different 2 mm posterior to the scleral spur between groups (p = 0.009), specifically with subclinical KC (p = 0.03). There is a trend where the asymmetry increases, although not significantly, with the KC degree (p &gt; 0.05). Conclusions: KC eyes presented significant thickness variations among eccentricities over the paracentral sclera. Although AST profiles did not differ between groups, the inferior\u2013superior asymmetry differences demonstrated scleral changes over the vertical meridian in KC that need further investigation.<\/jats:p>","DOI":"10.3390\/life13112223","type":"journal-article","created":{"date-parts":[[2023,11,20]],"date-time":"2023-11-20T00:30:50Z","timestamp":1700440250000},"page":"2223","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Anterior Scleral Thickness Profile in Keratoconus"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0508-1431","authenticated-orcid":false,"given":"Neus","family":"Burguera-Gim\u00e9nez","sequence":"first","affiliation":[{"name":"Anterior Segment and Cornea and External Eye Diseases Unit, Foundation Ophthalmological Medical Hospital (FOM), Av. P\u00edo Baroja, 12, E-46015 Valencia, Spain"},{"name":"Department of Optics and Optometry and Vision Sciences, Physics School, University of Valencia, Dr. Moliner, 50, E-46100 Valencia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8146-4039","authenticated-orcid":false,"given":"Mar\u00eda Amparo","family":"D\u00edez-Ajenjo","sequence":"additional","affiliation":[{"name":"Anterior Segment and Cornea and External Eye Diseases Unit, Foundation Ophthalmological Medical Hospital (FOM), Av. P\u00edo Baroja, 12, E-46015 Valencia, Spain"},{"name":"Department of Optics and Optometry and Vision Sciences, Physics School, University of Valencia, Dr. Moliner, 50, E-46100 Valencia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Noem\u00ed","family":"Burguera","sequence":"additional","affiliation":[{"name":"Q Vision, Ophthalmology Department, Vithas Virgen del Mar Hospital, Ctra. el Mami a Viator, Km.1, E-04120 Almer\u00eda, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristina","family":"Peris-Mart\u00ednez","sequence":"additional","affiliation":[{"name":"Anterior Segment and Cornea and External Eye Diseases Unit, Foundation Ophthalmological Medical Hospital (FOM), Av. P\u00edo Baroja, 12, E-46015 Valencia, Spain"},{"name":"Surgery Department, Ophthalmology, School of Medicine, University of Valencia, Av. Blasco Ib\u00e1\u00f1ez, 15, E-46010 Valencia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,19]]},"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. Ophthalmol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"8592","DOI":"10.1167\/iovs.11-7732","article-title":"Oxidative Stress in Keratoconus?","volume":"52","author":"Arnal","year":"2011","journal-title":"Investig. Ophthalmol. Vis. 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