{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,2]],"date-time":"2026-11-02T21:59:07Z","timestamp":1793656747553,"version":"4.5.1"},"reference-count":30,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2021,3,21]],"date-time":"2021-03-21T00:00:00Z","timestamp":1616284800000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2021,3,21]],"date-time":"2021-03-21T00:00:00Z","timestamp":1616284800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["BMC Ophthalmol"],"published-print":{"date-parts":[[2021,12]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n                <jats:title>Purpose<\/jats:title>\n                <jats:p>To assess the corneal endothelial cells morphology and count in keratoconus patients and their correlation with different stages of keratoconus.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Methods<\/jats:title>\n                <jats:p>Prospective non randomized multi-centric clinical study included 150 eyes of 150 keratoconus patients. Four centers in Egypt participated in this study included: Departments of Ophthalmology in Alexandria University, Tanta University and Port Said University and Alex I-Care hospital. Pentacam (Wavelight Oculyzer II) and specular microscopy (Tomey EM-3000) were done to all eyes. Keratoconic eyes were classified according to Amsler classification into stage 1, 2 and 3. Stage 1 included 99 eyes, stage 2 included 32 eyes &amp; stage 3 included 19 eyes.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>The mean age of keratoconus patients was 24.07\u2009\u00b1\u20096.154\u2009years. Forty five cases were males (30%) and 105 cases were females (70%). There was statistically significant difference in endothelial cell density (<jats:italic>p<\/jats:italic>\u2009&lt;\u20090.001) and coefficient of variation (<jats:italic>p<\/jats:italic>\u2009=\u20090.012) between different stages of keratoconus eyes. Regarding cell surface area, there was statistically significant difference in cell surface area between different stages of keratoconus eyes (<jats:italic>p<\/jats:italic>\u2009&lt;\u20090.001). In addition, for cell morphology, there was statistically significant difference between different stages of keratoconus eyes (<jats:italic>p<\/jats:italic>\u2009&lt;\u20090.001).<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>Qualitative and quantitative structural changes were seen in endothelial cells of keratoconus eyes by using specular microscopy. For stages 1 and 2, keratoconus may not affect the corneal endothelim significantly. The endothelium in stage 3 shows significant changes regarding polymegathism and pleomorphism.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1186\/s12886-021-01913-7","type":"journal-article","created":{"date-parts":[[2021,3,21]],"date-time":"2021-03-21T04:51:39Z","timestamp":1616302299000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Corneal endothelial cells changes in different stages of Keratoconus: a multi-Centre clinical study"],"prefix":"10.1186","volume":"21","author":[{"given":"Ahmed","family":"Elmassry","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ahmed","family":"Osman","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Moataz","family":"Sabry","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohamed","family":"Elmassry","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mai","family":"Katkat","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohamed Yousry","family":"Hatata","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohamed","family":"El-Kateb","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,3,21]]},"reference":[{"issue":"4","key":"1913_CR1","doi-asserted-by":"publisher","first-page":"379","DOI":"10.1038\/sj.eye.6700652","volume":"18","author":"T Georgiou","year":"2004","unstructured":"Georgiou T, Funnell CL, Cassels-Brown A, O'Conor R. 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