{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T18:08:46Z","timestamp":1784830126150,"version":"3.55.0"},"reference-count":18,"publisher":"BMJ","license":[{"start":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T00:00:00Z","timestamp":1784764800000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["Br J Ophthalmol"],"accepted":{"date-parts":[[2026,6,30]]},"abstract":"<jats:sec>\n                    <jats:title>Background\/aims<\/jats:title>\n                    <jats:p>The Early Treatment Diabetic Retinopathy Study (ETDRS) 7-field protocol remains the reference standard for diabetic retinopathy (DR) severity grading, but is technically demanding, poorly tolerated and covers only 30\u201335% of the retina. Ultra-widefield (UWF) imaging systems, including Clarus and Optos, provide 200\u00b0 retinal coverage with fewer acquisitions. This study evaluated agreement between ETDRS and UWF-based grading in non-proliferative DR.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      In this prospective study (\n                      <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"clintrialgov\" xlink:href=\"NCT05746975\">NCT05746975<\/jats:ext-link>\n                      ), 81 type 2 diabetes participants (147 eyes) with ETDRS-Diabetic Retinopathy Severity Scale (DRSS) levels 35\u201347 underwent ETDRS 7-field colour fundus photography (CFP) and UWF imaging using Clarus 500 and Optos California. ETDRS grids were superimposed on UWF images. Two masked graders assigned DRSS levels using three strategies: ETDRS 7-field alone, periphery-only and extended (ETDRS plus periphery). Agreement was assessed and peripheral lesions were analysed for frequency and association with DR severity.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Compared with ETDRS 7-field CFP, Clarus and Optos showed strong agreement in DR severity grading (Gwet\u2019s AC=0.774\u2009and 0.809, respectively). Agreement was slightly lower for CFP\u2013Clarus than CFP\u2013Optos, reflecting higher detection sensitivity with Clarus, particularly for intraretinal microvascular abnormality and haemorrhages. Peripheral lesions were frequent and when combined with ETDRS fields identified eyes with more advanced disease.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>The peripheral retina alone does not show increased lesion severity, but extended UWF imaging integrating central and peripheral fields provides a more complete assessment. Extended Clarus and Optos imaging closely align with ETDRS grading while detecting additional severe cases, supporting UWF imaging as an alternative to ETDRS photography in clinical trials and practice.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Trial registration number<\/jats:title>\n                    <jats:p>\n                      <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"clintrialgov\" xlink:href=\"NCT05746975\">NCT05746975<\/jats:ext-link>\n                      .\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bjo-2025-329382","type":"journal-article","created":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T17:20:20Z","timestamp":1784827220000},"page":"bjo-2025-329382","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["<b>Cross-device consistency in diabetic retinopathy grading: a comparative analysis of widefield versus standard 30\u201335<\/b>\n                    \u00b0\n                    <b>\u2013 the ClarusDR study<\/b>"],"prefix":"10.1136","clinical-trial-number":[{"clinical-trial-number":"nct05746975","registry":"10.18810\/clinical-trials-gov"},{"clinical-trial-number":"nct05746975","registry":"10.18810\/clinical-trials-gov"},{"clinical-trial-number":"nct05746975","registry":"10.18810\/clinical-trials-gov"},{"clinical-trial-number":"nct05746975","registry":"10.18810\/clinical-trials-gov"},{"clinical-trial-number":"nct05746975","registry":"10.18810\/clinical-trials-gov"},{"clinical-trial-number":"nct05746975","registry":"10.18810\/clinical-trials-gov"}],"author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3761-3292","authenticated-orcid":false,"given":"Ana Rita","family":"Santos","sequence":"first","affiliation":[{"name":"AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal"},{"name":"Center for Translational Health and Medical Biotechnology Research (TBIO)\/Health Research Network (RISE-Health), ESS, Polytechnic of Porto, Porto, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9873-8729","authenticated-orcid":false,"given":"Ana","family":"Almeida","sequence":"additional","affiliation":[{"name":"AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal"},{"name":"CORC \u2013 Coimbra Ophthalmology Reading Centre, Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-1236-0866","authenticated-orcid":false,"given":"In\u00eas","family":"Pinto","sequence":"additional","affiliation":[{"name":"AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal"},{"name":"CORC \u2013 Coimbra Ophthalmology Reading Centre, Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-9014-0362","authenticated-orcid":false,"given":"Ana Cl\u00e1udia","family":"Rocha","sequence":"additional","affiliation":[{"name":"AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal"},{"name":"CORC \u2013 Coimbra Ophthalmology Reading Centre, Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5403-8499","authenticated-orcid":false,"given":"Marta","family":"Lopes","sequence":"additional","affiliation":[{"name":"AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal"},{"name":"CORC \u2013 Coimbra Ophthalmology Reading Centre, Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1873-4320","authenticated-orcid":false,"given":"Torcato","family":"Santos","sequence":"additional","affiliation":[{"name":"AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal"},{"name":"CORC \u2013 Coimbra Ophthalmology Reading Centre, Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9170-6997","authenticated-orcid":false,"given":"In\u00eas Pereira","family":"Marques","sequence":"additional","affiliation":[{"name":"AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal"},{"name":"CORC \u2013 Coimbra Ophthalmology Reading Centre, Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8769-1355","authenticated-orcid":false,"given":"D\u00e9bora","family":"Reste-Ferreira","sequence":"additional","affiliation":[{"name":"AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0947-9850","authenticated-orcid":false,"given":"Jos\u00e9","family":"Cunha-Vaz","sequence":"additional","affiliation":[{"name":"AIBILI - Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal"},{"name":"Faculty of Medicine, University of Coimbra, Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2026,7,23]]},"reference":[{"key":"2026072310201214000_bjo-2025-329382v1.1","doi-asserted-by":"publisher","DOI":"10.1016\/S0161-6420(13)38012-9"},{"key":"2026072310201214000_bjo-2025-329382v1.2","doi-asserted-by":"publisher","DOI":"10.1016\/S0161-6420(91)32186-9"},{"key":"2026072310201214000_bjo-2025-329382v1.3","doi-asserted-by":"publisher","DOI":"10.1016\/j.ophtha.2013.05.004"},{"key":"2026072310201214000_bjo-2025-329382v1.4","doi-asserted-by":"publisher","DOI":"10.1016\/j.ophtha.2015.07.034"},{"key":"2026072310201214000_bjo-2025-329382v1.5","doi-asserted-by":"crossref","DOI":"10.1186\/s12886-018-1011-z","article-title":"Assessment of diabetic retinopathy using two ultra-wide-field fundus imaging systems, the Clarus and Optos systems","volume":"18","author":"Hirano","year":"2018","journal-title":"BMC Ophthalmol"},{"key":"2026072310201214000_bjo-2025-329382v1.6","doi-asserted-by":"publisher","DOI":"10.1097\/IAE.0b013e3182278b64"},{"key":"2026072310201214000_bjo-2025-329382v1.7","doi-asserted-by":"crossref","DOI":"10.1016\/j.ajo.2012.03.019","article-title":"Nonmydriatic ultrawide field retinal imaging compared with dilated standard 7-field 35-mm photography and retinal specialist examination for evaluation of diabetic retinopathy","volume":"154","author":"Silva","year":"2012","journal-title":"Am J Ophthalmol"},{"key":"2026072310201214000_bjo-2025-329382v1.8","doi-asserted-by":"publisher","DOI":"10.1016\/j.ophtha.2015.01.008"},{"key":"2026072310201214000_bjo-2025-329382v1.9","doi-asserted-by":"crossref","first-page":"527","DOI":"10.2147\/OPTH.S79448","article-title":"Optomap ultrawide field imaging identifies additional retinal abnormalities in patients with diabetic retinopathy","volume":"9","author":"Price","year":"2015","journal-title":"Clin Ophthalmol"},{"key":"2026072310201214000_bjo-2025-329382v1.10","doi-asserted-by":"crossref","DOI":"10.1016\/j.xops.2021.100029","article-title":"Comparison of Ultra-Widefield Imaging and Standard Imaging in Assessment of Early Treatment Diabetic Retinopathy Severity Scale","volume":"1","author":"Domalpally","year":"2021","journal-title":"Ophthalmol Sci"},{"key":"2026072310201214000_bjo-2025-329382v1.11","doi-asserted-by":"crossref","DOI":"10.1186\/s12886-024-03537-z","article-title":"ETDRS grading with CLARUS ultra-widefield images shows agreement with 7-fields colour fundus photography","volume":"24","author":"Santos","year":"2024","journal-title":"BMC Ophthalmol"},{"key":"2026072310201214000_bjo-2025-329382v1.12","doi-asserted-by":"crossref","unstructured":"Azzopardi M , Gridhar S , Tsika C , et al . A Comparison of Ultra-Widefield Imaging Quality Obtained with Zeiss Clarus and Optos for Virtual Medical Retina Services. 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