{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T09:52:35Z","timestamp":1790502755306,"version":"4.1.0"},"reference-count":96,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2023,10,24]],"date-time":"2023-10-24T00:00:00Z","timestamp":1698105600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of Manchester"},{"name":"Canon Medical EU, Zilverstraat, The Netherlands"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Imaging"],"abstract":"<jats:p>Several optical coherence tomography angiography (OCT-A) studies have demonstrated retinal microvascular changes in patients post-SARS-CoV-2 infection, reflecting retinal-systemic microvasculature homology. Post-COVID-19 syndrome (PCS) entails persistent symptoms following SARS-CoV-2 infection. In this study, we investigated the retinal microvasculature in PCS patients using OCT-angiography and analysed the macular retinal nerve fibre layer (RNFL) and ganglion cell layer (GCL) thickness via spectral domain-OCT (SD-OCT). Conducted at the Manchester Royal Eye Hospital, UK, this cross-sectional study compared 40 PCS participants with 40 healthy controls, who underwent ophthalmic assessments, SD-OCT, and OCT-A imaging. OCT-A images from the superficial capillary plexus (SCP) were analysed using an in-house specialised software, OCT-A vascular image analysis (OCTAVIA), measuring the mean large vessel and capillary intensity, vessel density, ischaemia areas, and foveal avascular zone (FAZ) area and circularity. RNFL and GCL thickness was measured using the OCT machine\u2019s software. Retinal evaluations occurred at an average of 15.2 \u00b1 6.9 months post SARS-CoV-2 infection in PCS participants. Our findings revealed no significant differences between the PCS and control groups in the OCT-A parameters or RNFL and GCL thicknesses, indicating that no long-term damage ensued in the vascular bed or retinal layers within our cohort, providing a degree of reassurance for PCS patients.<\/jats:p>","DOI":"10.3390\/jimaging9110234","type":"journal-article","created":{"date-parts":[[2023,10,25]],"date-time":"2023-10-25T04:14:47Z","timestamp":1698207287000},"page":"234","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Retinal Microvasculature Image Analysis Using Optical Coherence Tomography Angiography in Patients with Post-COVID-19 Syndrome"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1486-469X","authenticated-orcid":false,"given":"Maha","family":"Noor","sequence":"first","affiliation":[{"name":"Department of Eye Research, Manchester Royal Eye Hospital, Manchester University NHS Foundation Trust, Oxford Road, Manchester M13 9WL, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4302-7081","authenticated-orcid":false,"given":"Orlaith","family":"McGrath","sequence":"additional","affiliation":[{"name":"Department of Eye Research, Manchester Royal Eye Hospital, Manchester University NHS Foundation Trust, Oxford Road, Manchester M13 9WL, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ines","family":"Drira","sequence":"additional","affiliation":[{"name":"Department of Eye Research, Manchester Royal Eye Hospital, Manchester University NHS Foundation Trust, Oxford Road, Manchester M13 9WL, UK"},{"name":"Ophtalmologie D\u00e9partement, Centre Hospitalier Universitaire de Toulouse, 31300 Toulouse, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tariq","family":"Aslam","sequence":"additional","affiliation":[{"name":"Department of Eye Research, Manchester Royal Eye Hospital, Manchester University NHS Foundation Trust, Oxford Road, Manchester M13 9WL, UK"},{"name":"Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Oxford Road, Manchester M13 9PL, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"782","DOI":"10.1001\/jama.2020.12839","article-title":"Pathophysiology, Transmission, Diagnosis, and Treatment of Coronavirus Disease 2019 (COVID-19): A Review","volume":"324","author":"Wiersinga","year":"2020","journal-title":"JAMA"},{"key":"ref_2","unstructured":"National Institute of Health and Care Excellence (NICE) (2021). COVID-19 Rapid Guideline: Managing the Long-Term Effects of COVID-19, NICE. Available online: https:\/\/www.nice.org.uk\/guidance\/ng188."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"e102","DOI":"10.1016\/S1473-3099(21)00703-9","article-title":"A clinical case definition of post-COVID-19 condition by a Delphi consensus","volume":"22","author":"Soriano","year":"2022","journal-title":"Lancet Infect. Dis."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"601","DOI":"10.1038\/s41591-021-01283-z","article-title":"Post-acute COVID-19 syndrome","volume":"27","author":"Nalbandian","year":"2021","journal-title":"Nat. Med."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"e86002","DOI":"10.7554\/eLife.86002","article-title":"Pathogenic mechanisms of post-acute sequelae of SARS-CoV-2 infection (PASC)","volume":"12","author":"Sherif","year":"2023","journal-title":"eLife"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"e161167","DOI":"10.1172\/JCI161167","article-title":"Long COVID endotheliopathy: Hypothesized mechanisms and potential therapeutic approaches","volume":"132","author":"Ahamed","year":"2022","journal-title":"J. Clin. Investig."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"102","DOI":"10.3390\/neurolint13010010","article-title":"Acute and Post-Acute Neurological Complications of COVID-19","volume":"13","author":"Shah","year":"2021","journal-title":"Neurol. Int."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"ofaa509","DOI":"10.1093\/ofid\/ofaa509","article-title":"Postacute COVID-19: An Overview and Approach to Classification","volume":"7","author":"Amenta","year":"2020","journal-title":"Open Forum Infect. Dis."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"219","DOI":"10.1016\/j.jocn.2021.04.001","article-title":"Post-COVID 19 neurological syndrome: Implications for sequelae\u2019s treatment","volume":"88","author":"Janjua","year":"2021","journal-title":"J. Clin. Neurosci."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"911","DOI":"10.1038\/s41591-022-01810-6","article-title":"Unexplained post-acute infection syndromes","volume":"28","author":"Choutka","year":"2022","journal-title":"Nat. Med."},{"key":"ref_11","first-page":"384","article-title":"Post-COVID-19 syndrome: Epidemiology, diagnostic criteria and pathogenic mechanisms involved","volume":"72","year":"2021","journal-title":"Rev. Nuerol."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Cort\u00e9s-Telles, A., L\u00f3pez-Romero, S., Figueroa-Hurtado, E., Pou-Aguilar, Y.N., Wong, A.W., Milne, K.M., Ryerson, C.J., and Guenette, J.A. (2021). Pulmonary function and functional capacity in COVID-19 survivors with persistent dyspnoea. Respir. Physiol. Neurobiol., 288.","DOI":"10.1016\/j.resp.2021.103644"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1349","DOI":"10.12688\/f1000research.27287.2","article-title":"\u2018The long tail of COVID-19\u2019\u2014The detection of a prolonged inflammatory response after a SARS-CoV-2 infection in asymptomatic and mildly affected patients","volume":"9","author":"Doykov","year":"2021","journal-title":"F1000 Res."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1186\/s13027-023-00485-z","article-title":"Potential molecular mechanisms of chronic fatigue in long haul COVID and other viral diseases","volume":"18","author":"Gottschalk","year":"2023","journal-title":"Infect. Agent Cancer"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Fern\u00e1ndez-De-Las-Pe\u00f1as, C., Palacios-Ce\u00f1a, D., G\u00f3mez-Mayordomo, V., Cuadrado, M.L., and Florencio, L.L. (2021). Defining Post-COVID Symptoms (Post-Acute COVID, Long COVID, Persistent Post-COVID): An Integrative Classification. Int. J. Environ. Res. Public Health, 18.","DOI":"10.3390\/ijerph18052621"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Andrade, B.S., Siqueira, S., Soares, W.R.d.A., Rangel, F.d.S., Santos, N.O., Freitas, A.d.S., da Silveira, P.R., Tiwari, S., Alzahrani, K.J., and G\u00f3es-Neto, A. (2021). Long-COVID and Post-COVID Health Complications: An Up-to-Date Review on Clinical Conditions and Their Possible Molecular Mechanisms. Viruses, 13.","DOI":"10.3390\/v13040700"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"323","DOI":"10.1177\/1945892420957853","article-title":"A Systematic Review of the Neuropathologic Findings of Post-Viral Olfactory Dysfunction: Implications and Novel Insight for the COVID-19 Pandemic","volume":"35","author":"Lee","year":"2020","journal-title":"Am. J. Rhinol. Allergy"},{"key":"ref_18","first-page":"1891","article-title":"Long Covid: Where we stand and challenges ahead","volume":"29","author":"Mantovani","year":"2022","journal-title":"Cell Death Differ."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"e885","DOI":"10.1097\/PR9.0000000000000885","article-title":"Neurobiology of SARS-CoV-2 interactions with the peripheral nervous system: Implications for COVID-19 and pain","volume":"6","author":"McFarland","year":"2021","journal-title":"Pain Rep."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"66","DOI":"10.1007\/s12016-021-08848-3","article-title":"A Review of Persistent Post-COVID Syndrome (PPCS)","volume":"64","author":"Oronsky","year":"2023","journal-title":"Clin. Rev. Allergy Immunol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"533","DOI":"10.1016\/S2213-2600(21)00125-9","article-title":"Confronting COVID-19-associated cough and the post-COVID syndrome: Role of viral neurotropism, neuroinflammation, and neuroimmune responses","volume":"9","author":"Song","year":"2021","journal-title":"Lancet Respir. Med."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"883","DOI":"10.3233\/JAD-210335","article-title":"Dementia and COVID-19, a Bidirectional Liaison: Risk Factors, Biomarkers, and Optimal Health Care","volume":"82","author":"Toniolo","year":"2021","journal-title":"J. Alzheimer\u2019s Dis."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1257","DOI":"10.1016\/j.cjco.2021.05.020","article-title":"Cardiovascular and Renal Risk Factors and Complications Associated with COVID-19","volume":"3","author":"Touyz","year":"2021","journal-title":"CJC Open"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1064","DOI":"10.1111\/jth.15267","article-title":"Prolonged elevation of D-dimer levels in convalescent COVID-19 patients is independent of the acute phase response","volume":"19","author":"Townsend","year":"2021","journal-title":"J. Thromb. Haemost."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"425","DOI":"10.47102\/annals-acadmedsg.202175","article-title":"ST-segment elevation myocardial infarction in post-COVID-19 patients: A case series","volume":"50","author":"Wong","year":"2021","journal-title":"Ann. Acad. Med. Singap."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"162","DOI":"10.1186\/s12967-021-02833-2","article-title":"Pathophysiology of skeletal muscle disturbances in Myalgic Encephalomyelitis\/Chronic Fatigue Syndrome (ME\/CFS)","volume":"19","author":"Wirth","year":"2021","journal-title":"J. Transl. Med."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"537","DOI":"10.1042\/BCJ20220016","article-title":"A central role for amyloid fibrin microclots in long COVID\/PASC: Origins and therapeutic implications","volume":"479","author":"Kell","year":"2022","journal-title":"Biochem. J."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Szewczykowski, C., Mardin, C., Lucio, M., Wallukat, G., Hoffmanns, J., Schr\u00f6der, T., Raith, F., Rogge, L., Heltmann, F., and Moritz, M. (2022). Long COVID: Association of Functional Autoantibodies against G-Protein-Coupled Receptors with an Impaired Retinal Microcirculation. Int. J. Mol. Sci., 23.","DOI":"10.3390\/ijms23137209"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"241","DOI":"10.1016\/j.ijid.2022.01.007","article-title":"Symptoms Experienced at the Acute Phase of SARS-CoV-2 Infection as Risk Factor of Long-term Post-COVID Symptoms: The LONG-COVID-EXP-CM Multicenter Study","volume":"116","author":"Florencio","year":"2022","journal-title":"Int. J. Infect. Dis."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"639","DOI":"10.1038\/s41586-021-03207-w","article-title":"Evolution of antibody immunity to SARS-CoV-2","volume":"591","author":"Gaebler","year":"2021","journal-title":"Nature"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"324","DOI":"10.1136\/thoraxjnl-2020-216226","article-title":"COVID-19 and what comes after?","volume":"76","author":"Hopkinson","year":"2021","journal-title":"Thorax"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1017","DOI":"10.1038\/s41591-020-0968-3","article-title":"Extrapulmonary manifestations of COVID-19","volume":"26","author":"Gupta","year":"2020","journal-title":"Nat. Med."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"2546","DOI":"10.1111\/jth.15490","article-title":"Persistent endotheliopathy in the pathogenesis of long COVID syndrome","volume":"19","author":"Fogarty","year":"2021","journal-title":"J. Thromb. Haemost."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"754667","DOI":"10.3389\/fmed.2021.754667","article-title":"Case Report: Neutralization of Autoantibodies Targeting G-Protein-Coupled Receptors Improves Capillary Impairment and Fatigue Symptoms After COVID-19 Infection","volume":"8","author":"Hohberger","year":"2021","journal-title":"Front. Med."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1636","DOI":"10.1093\/cid\/ciac961","article-title":"The Epidemiology of Long COVID in US Adults","volume":"76","author":"Robertson","year":"2022","journal-title":"Clin. Infect. Dis."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"3528","DOI":"10.1038\/s41467-022-30836-0","article-title":"Long COVID burden and risk factors in 10 UK longitudinal studies and electronic health records","volume":"13","author":"Thompson","year":"2022","journal-title":"Nat. Commun."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1706","DOI":"10.1038\/s41591-022-01909-w","article-title":"Symptoms and risk factors for long COVID in non-hospitalized adults","volume":"28","author":"Subramanian","year":"2022","journal-title":"Nat. Med."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1593","DOI":"10.1093\/infdis\/jiac136","article-title":"Global Prevalence of Post-Coronavirus Disease 2019 (COVID-19) Condition or Long COVID: A Meta-Analysis and Systematic Review","volume":"226","author":"Chen","year":"2022","journal-title":"J. Infect. Dis."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"881","DOI":"10.1016\/j.cell.2022.01.014","article-title":"Multiple early factors anticipate post-acute COVID-19 sequelae","volume":"185","author":"Su","year":"2022","journal-title":"Cell"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1943","DOI":"10.1007\/s11606-021-07242-1","article-title":"Post-COVID-19 Syndrome in Outpatients: A Cohort Study","volume":"37","author":"Desgranges","year":"2022","journal-title":"J. Gen. Intern. Med."},{"key":"ref_41","unstructured":"Hanson, S.W., Abbafati, C., and Aerts, J. (2022). A global systematic analysis of the occurrence, severity, and recovery pattern of long COVID in 2020 and 2021. medRxiv."},{"key":"ref_42","unstructured":"Office for National Statistics (ONS) (2023, March 15). Prevalence of Ongoing Symptoms Following Coronavirus (COVID-19) Infection in the UK: 2 February 2023, Available online: https:\/\/www.ons.gov.uk\/peoplepopulationandcommunity\/healthandsocialcare\/conditionsanddiseases\/bulletins\/prevalenceofongoingsymptomsfollowingcoronaviruscovid19infectionintheuk\/2february2023."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"101019","DOI":"10.1016\/j.eclinm.2021.101019","article-title":"Characterizing long COVID in an international cohort: 7 months of symptoms and their impact","volume":"38","author":"Davis","year":"2021","journal-title":"EClinicalMedicine"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"422","DOI":"10.1186\/s13054-020-03120-0","article-title":"Role of angiotensin-converting enzyme 2 (ACE2) in COVID-19","volume":"24","author":"Ni","year":"2020","journal-title":"Crit. Care"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"1456","DOI":"10.1161\/CIRCRESAHA.120.317015","article-title":"Angiotensin-Converting Enzyme 2: SARS-CoV-2 Receptor and Regulator of the Renin-Angiotensin System","volume":"126","author":"Gheblawi","year":"2020","journal-title":"Circ. Res."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"1546","DOI":"10.4103\/ijo.IJO_1319_20","article-title":"Clinical profile and prevalence of conjunctivitis in mild COVID-19 patients in a tertiary care COVID-19 hospital: A retrospective cross-sectional study","volume":"68","author":"Lomi","year":"2020","journal-title":"Indian J. Ophthalmol."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"11085","DOI":"10.1038\/s41598-021-90482-2","article-title":"Ocular findings among patients surviving COVID-19","volume":"11","author":"Costa","year":"2021","journal-title":"Sci. Rep."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"488","DOI":"10.4103\/ijo.IJO_297_21","article-title":"COVID-19 and Eye: A Review of Ophthalmic Manifestations of COVID-19","volume":"69","author":"Honavar","year":"2021","journal-title":"Indian J. Ophthalmol."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"1204","DOI":"10.1097\/ICO.0000000000002795","article-title":"Anterior Scleritis Manifesting After Coronavirus Disease 2019: A Report of Two Cases","volume":"40","author":"Feizi","year":"2021","journal-title":"Cornea"},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"4827304","DOI":"10.1155\/2020\/4827304","article-title":"Ocular Findings in COVID-19 Patients: A Review of Direct Manifestations and Indirect Effects on the Eye","volume":"2020","author":"Bertoli","year":"2020","journal-title":"J. Ophthalmol."},{"key":"ref_51","first-page":"98","article-title":"COVID-19-Related Retinal Micro-vasculopathy\u2014A Review of Current Evidence","volume":"235","author":"Teo","year":"2021","journal-title":"Arch. Ophthalmol."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"323","DOI":"10.1007\/s10792-021-01996-7","article-title":"Retinal manifestations in patients with SARS-CoV-2 infection and pathogenetic implications: A systematic review","volume":"42","author":"Sen","year":"2022","journal-title":"Int. Ophthalmol."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"1308","DOI":"10.1136\/bjophthalmol-2020-318236","article-title":"Retinal microvascular signs in COVID-19","volume":"106","author":"Sim","year":"2022","journal-title":"Br. J. Ophthalmol."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"1610","DOI":"10.1016\/S0140-6736(20)31014-X","article-title":"Retinal findings in patients with COVID-19","volume":"395","author":"Marinho","year":"2020","journal-title":"Lancet"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"2153","DOI":"10.1038\/s41433-020-1084-9","article-title":"Concerns about the interpretation of OCT and fundus findings in COVID-19 patients in recent Lancet publication","volume":"34","author":"Vavvas","year":"2020","journal-title":"Eye"},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"e35","DOI":"10.1016\/S0140-6736(20)31921-8","article-title":"Seeking clarity on retinal findings in patients with COVID-19","volume":"396","author":"Ouyang","year":"2020","journal-title":"Lancet"},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"628","DOI":"10.1177\/11206721211001019","article-title":"Optic nerve and macular optical coherence tomography in recovered COVID-19 patients","volume":"32","author":"Martin","year":"2022","journal-title":"Eur. J. Ophthalmol."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"102726","DOI":"10.1016\/j.pdpdt.2022.102726","article-title":"Retinal findings of COVID-19 patients using ocular coherence tomography angiography two to three months after infection: Ocular appearance recovered COVID-19 patient","volume":"38","author":"Dehghani","year":"2022","journal-title":"Photodiagnos. Photodyn. Ther."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"717","DOI":"10.1080\/08164622.2021.1916389","article-title":"Quantitative assessment of retinal changes in COVID-19 patients","volume":"104","author":"Oren","year":"2021","journal-title":"Clin. Exp. Optom."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"469","DOI":"10.1016\/j.jdiacomp.2015.12.025","article-title":"Abnormalities of retinal ganglion cell complex at optical coherence tomography in patients with type 2 diabetes: A sign of diabetic polyneuropathy, not retinopathy","volume":"30","author":"Salvi","year":"2016","journal-title":"J. Diabetes Complicat."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1111\/j.1469-7580.2005.00395.x","article-title":"Retinal vascular image analysis as a potential screening tool for cerebrovascular disease: A rationale based on homology between cerebral and retinal microvasculatures","volume":"206","author":"Patton","year":"2005","journal-title":"J. Anat."},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"559","DOI":"10.1136\/bjophthalmol-2020-317953","article-title":"Retinal microvascular abnor-malities in patients after COVID-19 depending on disease severity","volume":"106","author":"Zapata","year":"2022","journal-title":"Br. J. Ophthalmol."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1016\/j.jcjo.2020.12.021","article-title":"Optical coherence tomography angiography findings in patients with COVID-19","volume":"56","author":"Turker","year":"2021","journal-title":"Can. J. Ophthalmol."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"24","DOI":"10.1016\/j.jcjo.2020.11.006","article-title":"Optical coherence tomography angiography analysis of the retina in patients recovered from COVID-19: A case-control study","volume":"56","author":"Abrishami","year":"2021","journal-title":"Can. J. Ophthalmol."},{"key":"ref_65","doi-asserted-by":"crossref","unstructured":"Gonz\u00e1lez-Zamora, J., Bilbao-Malav\u00e9, V., G\u00e1ndara, E., Casablanca-Pi\u00f1era, A., Boquera-Ventosa, C., Landecho, M.F., Zarranz-Ventura, J., and Garc\u00eda-Layana, A. (2021). Retinal Microvascular Impairment in COVID-19 Bilateral Pneumonia Assessed by Optical Coherence Tomography Angiography. Biomedicines, 9.","DOI":"10.3390\/biomedicines9030247"},{"key":"ref_66","doi-asserted-by":"crossref","first-page":"102267","DOI":"10.1016\/j.pdpdt.2021.102267","article-title":"Macular vessel density in patients recovered from COVID 19","volume":"34","author":"Hazar","year":"2021","journal-title":"Photodiagnos. Photodyn. Ther."},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"2243","DOI":"10.1007\/s00417-021-05186-0","article-title":"Reduced macular vessel density in COVID-19 patients with and without associated thrombotic events using optical coherence tomography angiography","volume":"259","year":"2021","journal-title":"Graefe\u2019s Arch. Clin. Exp. Ophthalmol."},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"842","DOI":"10.1080\/08164622.2021.1978817","article-title":"Optical coherence tomography angiography of retinal vasculature in recovered COVID-19 patients compared to age and ethnic matched controls","volume":"105","author":"Rodman","year":"2022","journal-title":"Clin. Exp. Optom."},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"324","DOI":"10.4274\/tjo.galenos.2022.87036","article-title":"Evaluation of Retinal Microvascular Impairment after COVID-19 and Its Clinical Correlates Using Optical Coherence Tomography Angiography","volume":"52","year":"2022","journal-title":"Turk. J. Ophthalmol."},{"key":"ref_70","doi-asserted-by":"crossref","first-page":"848","DOI":"10.1080\/08164622.2021.1999770","article-title":"Analysis of swept-source optical coherence tomography angiography measurement al-terations in adult patients recovered from COVID-19","volume":"105","author":"Cetinkaya","year":"2022","journal-title":"Clin. Exp. Optom."},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"771","DOI":"10.1007\/s00417-021-05429-0","article-title":"Macular vessel density re-duction in patients recovered from COVID-19: A longitudinal optical coherence tomography angiography study","volume":"260","author":"Abrishami","year":"2022","journal-title":"Graefe\u2019s Arch. Clin. Exp. Ophthalmol."},{"key":"ref_72","first-page":"1175","article-title":"Post COVID-19 Retinal Evaluation Using Optical Coherence Tomography Angiography: A Case Control Study","volume":"31","author":"Macky","year":"2022","journal-title":"Ocul. Immunol. Inflamm."},{"key":"ref_73","doi-asserted-by":"crossref","first-page":"182","DOI":"10.1016\/j.ajo.2021.03.015","article-title":"Optical Coherence Tomography Angiography Features in Post-COVID-19 Pneumonia Patients: A Pilot Study","volume":"227","author":"Cennamo","year":"2021","journal-title":"Am. J. Ophthalmol."},{"key":"ref_74","doi-asserted-by":"crossref","unstructured":"Bilbao-Malav\u00e9, V., Gonz\u00e1lez-Zamora, J., de Viteri, M.S., de la Puente, M., G\u00e1ndara, E., Casablanca-Pi\u00f1era, A., Boquera-Ventosa, C., Zarranz-Ventura, J., Landecho, M.F., and Garc\u00eda-Layana, A. (2021). Persistent Retinal Microvascular Impairment in COVID-19 Bilateral Pneumonia at 6-Months Follow-Up Assessed by Optical Coherence Tomography Angiography. Biomedicines, 9.","DOI":"10.3390\/biomedicines9050502"},{"key":"ref_75","doi-asserted-by":"crossref","first-page":"e000867","DOI":"10.1136\/bmjophth-2021-000867","article-title":"Persistent reduction of retinal microvascular vessel density in patients with moderate and severe COVID-19 disease","volume":"7","author":"Azarfane","year":"2022","journal-title":"BMJ Open Ophthalmol."},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"971","DOI":"10.1136\/bjo.82.8.971","article-title":"People and eyes: Statistical approaches in ophthalmology","volume":"82","author":"Morris","year":"1998","journal-title":"Br. J. Ophthalmol."},{"key":"ref_77","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1167\/tvst.9.5.10","article-title":"The Impact of Deterministic Signal Loss on OCT Angiography Measurements","volume":"9","author":"Erdei","year":"2020","journal-title":"Transl. Vis. Vision Sci. Technol."},{"key":"ref_78","doi-asserted-by":"crossref","unstructured":"Early Treatment Diabetic Retinopathy Study Research Group (1991). Early Photocoagulation for Diabetic Retinopathy: ETDRS Report Number 9. Ophthalmology, 98, 766\u2013785.","DOI":"10.1016\/S0161-6420(13)38011-7"},{"key":"ref_79","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1167\/tvst.9.4.2","article-title":"Differentiation of Diabetic Status Using Statistical and Machine Learning Techniques on Optical Coherence Tomography Angiography Images","volume":"9","author":"Aslam","year":"2020","journal-title":"Transl. Vis. Sci. Technol."},{"key":"ref_80","doi-asserted-by":"crossref","first-page":"648","DOI":"10.1038\/s41433-018-0286-x","article-title":"Optical coherence tomography angiography characteristics in diabetic patients without clinical diabetic retinopathy","volume":"33","author":"Thompson","year":"2019","journal-title":"Eye"},{"key":"ref_81","first-page":"1545","article-title":"Foveal avascular zone area and parafoveal vessel density measurements in different stages of diabetic retinopathy by optical coherence tomography angiography","volume":"10","author":"Mastropasqua","year":"2017","journal-title":"Int. J. Ophthalmol."},{"key":"ref_82","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1016\/j.visres.2016.09.019","article-title":"Acircularity index and axis ratio of the foveal avascular zone in diabetic eyes and healthy controls measured by optical coherence tomography angiography","volume":"139","author":"Krawitz","year":"2017","journal-title":"Vis. Res."},{"key":"ref_83","unstructured":"(2020, January 01). The Jamovi Project [Computer Software]. Available online: http:\/\/www.jamovi.org."},{"key":"ref_84","unstructured":"National Institute of Health and Care Excellence (NICE) (2021). COVID-19 Rapid Evidence Review: Risk Factors for Long-Term Effects of COVID-19, NICE. Available online: https:\/\/files.magicapp.org\/guideline\/08d10c67-1331-4146-9471-b15d1d93e707\/files\/Evidence_review_for_risk_factors_FINAL_r400881.pdf."},{"key":"ref_85","doi-asserted-by":"crossref","first-page":"75","DOI":"10.1016\/j.jcjo.2021.06.019","article-title":"SD-OCT assessment of macular and optic nerve alterations in patients recovered from COVID-19","volume":"57","author":"Yalcinbayir","year":"2022","journal-title":"Can. J. Ophthalmol."},{"key":"ref_86","doi-asserted-by":"crossref","unstructured":"Ugurlu, A., Agcayazi, S.B., Icel, E., Budakoglu, O., Unver, E., Barkay, O., Karake\u00e7ili, F., and Bayrakceken, K. (2023, April 24). Assessment of the optic nerve, macular, and retinal vascular effects of COVID-19. Available online: https:\/\/www.sciencedirect.com\/science\/article\/pii\/S0008418222001892.","DOI":"10.1016\/j.jcjo.2022.06.016"},{"key":"ref_87","doi-asserted-by":"crossref","first-page":"107263","DOI":"10.1016\/j.clineuro.2022.107263","article-title":"Headache and cognitive disturbance correlate with ganglion cell layer thickness in patients who recovered from COVID-19","volume":"217","author":"Eroglu","year":"2022","journal-title":"Clin. Neurol. Neurosurg."},{"key":"ref_88","doi-asserted-by":"crossref","first-page":"103108","DOI":"10.1016\/j.pdpdt.2022.103108","article-title":"Evaluation of retinal and choroidal parameters as neurodegeneration biomarkers in patients with post-COVID-19 syndrome","volume":"40","author":"Kanra","year":"2022","journal-title":"Photodiagnos. Photodyn. Ther."},{"key":"ref_89","doi-asserted-by":"crossref","unstructured":"Schlick, S., Lucio, M., Wallukat, G., Bartsch, A., Skornia, A., Hoffmanns, J., Szewczykowski, C., Schr\u00f6der, T., Raith, F., and Rogge, L. (2022). Post-COVID-19 Syndrome: Retinal Microcirculation as a Potential Marker for Chronic Fatigue. Int. J. Mol. Sci., 23.","DOI":"10.1101\/2022.09.23.22280264"},{"key":"ref_90","doi-asserted-by":"crossref","unstructured":"Jevnikar, K., Megli\u010d, A., Lapajne, L., Logar, M., Valentin\u010di\u010d, N.V., Petrovi\u010d, M.G., and Mekjavi\u0107, P.J. (2023). The Comparison of Retinal Microvascular Findings in Acute COVID-19 and 1-Year after Hospital Discharge Assessed with Multimodal Imaging\u2014A Prospective Longitudinal Cohort Study. Int. J. Mol. Sci., 24.","DOI":"10.3390\/ijms24044032"},{"key":"ref_91","doi-asserted-by":"crossref","first-page":"684","DOI":"10.1080\/09273948.2021.1896008","article-title":"An Update on COVID-19 Related Ophthalmic Manifestations","volume":"29","author":"Jevnikar","year":"2021","journal-title":"Ocul. Immunol. Inflamm."},{"key":"ref_92","doi-asserted-by":"crossref","first-page":"75","DOI":"10.1186\/s13098-020-00586-4","article-title":"Severity and mortality of COVID 19 in patients with diabetes, hypertension and cardiovascular disease: A meta-analysis","volume":"12","author":"Dualib","year":"2020","journal-title":"Diabetol. Metab. Syndr."},{"key":"ref_93","doi-asserted-by":"crossref","first-page":"2157","DOI":"10.1007\/s00417-020-05070-3","article-title":"Retinal capillary involvement in early post-COVID-19 patients: A healthy controlled study","volume":"259","author":"Savastano","year":"2021","journal-title":"Graefe\u2019s Arch. Clin. Exp. Ophthalmol."},{"key":"ref_94","doi-asserted-by":"crossref","unstructured":"Szkodny, D., Wyl\u0119ga\u0142a, E., Sujka-Franczak, P., Chlasta-Twardzik, E., Fiolka, R., Tomczyk, T., and Wyl\u0119ga\u0142a, A. (2021). Retinal OCT Findings in Patients after COVID Infection. J. Clin. Med., 10.","DOI":"10.3390\/jcm10153233"},{"key":"ref_95","doi-asserted-by":"crossref","unstructured":"Kal, M., Winiarczyk, M., Cie\u015bla, E., P\u0142atkowska-Adamska, B., Walczyk, A., Biskup, M., Pabjan, P., G\u0142uszek, S., Odrobina, D., and Mackiewicz, J. (2022). Retinal Microvascular Changes in COVID-19 Bilateral Pneumonia Based on Optical Coherence Tomography Angiography. J. Clin. Med., 11.","DOI":"10.3390\/jcm11133621"},{"key":"ref_96","doi-asserted-by":"crossref","first-page":"927121","DOI":"10.3389\/fmed.2022.927121","article-title":"Optical Coherence Tomography Angiography Analysis of Vessel Density Indices in Early Post-COVID-19 Patients","volume":"9","author":"Chiosi","year":"2022","journal-title":"Front. Med."}],"container-title":["Journal of Imaging"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2313-433X\/9\/11\/234\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T21:11:13Z","timestamp":1760130673000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2313-433X\/9\/11\/234"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,10,24]]},"references-count":96,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2023,11]]}},"alternative-id":["jimaging9110234"],"URL":"https:\/\/doi.org\/10.3390\/jimaging9110234","relation":{},"ISSN":["2313-433X"],"issn-type":[{"value":"2313-433X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,10,24]]}}}