{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T06:18:26Z","timestamp":1787811506253,"version":"build-2784847793"},"reference-count":34,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:00:00Z","timestamp":1787788800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Med."],"abstract":"<jats:sec>\n                    <jats:title>Aim<\/jats:title>\n                    <jats:p>This study aimed to investigate the effect of COVID-19 infection on corneal endothelial cell density and morphology, and to analyze the related factors.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This cross-sectional study included patients who underwent corneal endothelial examination at our institute from August 2022 to May 2023. Patients were categorized into COVID-19 recovery group and non-COVID-19-infection group according to their SARS-CoV-2 infection history. Endothelial cell density (ECD), s tandard deviation of cell area (SD-Area), average cell area (ACA), and hexagonal cell percentage (HEX), among others, were compared between the two groups. To account for confounding factors, univariate analysis assessed the relationship between COVID-19 infection, demographics, medical history, and corneal endothelial cell characteristics. Subsequently, multiple linear regression pinpointed independent factors linked to cell density and morphology.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Three hundred seventy-eight patients recovering from COVID-19 and 382 individuals without a history of COVID-19 infection were included in the study. Analysis of corneal endothelial parameters demonstrated a statistically significant decrease in ECD (\n                      <jats:italic>p<\/jats:italic>\n                      \u202f&amp;lt;\u202f0.001) and HEX (\n                      <jats:italic>p<\/jats:italic>\n                      \u202f=\u202f0.005) in the COVID-19 recovery group compared to the non-COVID-19 infection group. Additionally, higher SD-Area (\n                      <jats:italic>p<\/jats:italic>\n                      \u202f&amp;lt;\u202f0.001), increased ACA (\n                      <jats:italic>p<\/jats:italic>\n                      \u202f&amp;lt;\u202f0.001), and greater MAX (\n                      <jats:italic>p<\/jats:italic>\n                      \u202f&amp;lt;\u202f0.001) were observed in the COVID-19 recovery group. Multiple linear regression analysis suggested that COVID-19 infection history and advanced age were independent factors associated with decreased corneal endothelial density and irregular morphology.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>A history of COVID-19 infection was found to be significantly associated with decreased corneal endothelial cell density and altered morphology in convalescent patients. While these findings suggest potential long-term ocular surface implications, further prospective studies with pre-infection baselines are warranted to establish causality and to define specific, evidence-based guidelines for perioperative corneal endothelial protection in this population.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fmed.2026.1878263","type":"journal-article","created":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T05:35:10Z","timestamp":1787808910000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Impact of COVID-19 on corneal endothelial density and morphology: a cross-sectional study in convalescent patients"],"prefix":"10.3389","volume":"13","author":[{"given":"Ling","family":"Zhang","sequence":"first","affiliation":[{"name":"Department of Ophthalmology, The Second Affiliated Hospital of Fujian Medical University","place":["Quanzhou, Fujian, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenjian","family":"Shi","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, The Second Affiliated Hospital of Fujian Medical University","place":["Quanzhou, Fujian, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiumei","family":"Guo","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, The Second Affiliated Hospital of Fujian Medical University","place":["Quanzhou, Fujian, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Runhua","family":"Lv","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, The Second Affiliated Hospital of Fujian Medical University","place":["Quanzhou, Fujian, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huilin","family":"Guan","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, The Second Affiliated Hospital of Fujian Medical University","place":["Quanzhou, Fujian, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Feng","family":"Zheng","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, The Second Affiliated Hospital of Fujian Medical University","place":["Quanzhou, Fujian, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yingying","family":"Gao","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, The Second Affiliated Hospital of Fujian Medical University","place":["Quanzhou, Fujian, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,8,27]]},"reference":[{"key":"ref1","year":"2023"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"141","DOI":"10.1038\/s41579-020-00459-7","article-title":"Characteristics of SARS-CoV-2 and COVID-19","volume":"19","author":"Hu","year":"2021","journal-title":"Nat Rev 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