{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T02:18:47Z","timestamp":1785377927211,"version":"3.55.0"},"reference-count":36,"publisher":"BMJ","issue":"7","funder":[{"DOI":"10.13039\/100008071","name":"Glaucoma Research Society of Canada","doi-asserted-by":"publisher","award":["N\/A"],"award-info":[{"award-number":["N\/A"]}],"id":[{"id":"10.13039\/100008071","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000024","name":"Canadian Institutes of Health Research","doi-asserted-by":"publisher","award":["PJT159564"],"award-info":[{"award-number":["PJT159564"]}],"id":[{"id":"10.13039\/501100000024","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100007817","name":"Alcon Research Institute","doi-asserted-by":"publisher","award":["N\/A"],"award-info":[{"award-number":["N\/A"]}],"id":[{"id":"10.13039\/100007817","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["Br J Ophthalmol"],"accepted":{"date-parts":[[2023,9,3]]},"published-print":{"date-parts":[[2024,7]]},"abstract":"<jats:sec>\n<jats:title>Background\/aims<\/jats:title>\n<jats:p>Optical coherence tomography angiography (OCT-A) images are subject to variability, but the extent to which learning impacts OCT-A measurements is unknown. We determined whether there is a learning effect in glaucoma patients and healthy controls imaged with OCT-A.<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title>Methods<\/jats:title>\n<jats:p>Ninety-one open-angle glaucoma patients and 54 healthy controls were imaged every 4 months over a period of approximately 1\u2009year in this longitudinal cohort study. We analysed 15\u00b0\u00d715\u00b0 scans, centred on the fovea, in one eye of each participant. Two-dimensional projection images for the superficial, intermediate and deep vascular plexuses were exported and binarised after which perfusion density was calculated. Linear mixed-effects models were used to investigate the association between perfusion density and follow-up time.<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title>Results<\/jats:title>\n<jats:p>The mean (SD) age of glaucoma patients and healthy controls was 67.3 (8.1) years and 62.1 (9.0) years, respectively. There was a significant correlation between perfusion density and scan quality in both glaucoma patients (r=0.50 (95% CI 0.42 to 0.58); p&lt;0.05) and healthy controls (r=0.41 (95% CI 0.29 to 0.52); p&lt;0.05). An increase in perfusion density occurred over time and persisted, even after adjustment for scan quality (1.75% per year (95%\u2009CI 1.14 to 2.37), p&lt;0.01).<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title>Conclusions<\/jats:title>\n<jats:p>Perfusion density measurements are subject to increasing experience of either the operator or participant, or a combination of both. These findings have implications for the interpretation of longitudinal measurements with OCT-A.<\/jats:p>\n<\/jats:sec>","DOI":"10.1136\/bjo-2022-322979","type":"journal-article","created":{"date-parts":[[2023,10,19]],"date-time":"2023-10-19T17:24:41Z","timestamp":1697736281000},"page":"978-983","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":3,"title":["Variability of scan quality and perfusion density in longitudinal optical coherence tomography angiography imaging"],"prefix":"10.1136","volume":"108","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3653-9003","authenticated-orcid":false,"given":"Corey A","family":"Smith","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vanessa L","family":"Josey","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael E","family":"West","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oksana M","family":"Dyachok","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Glen P","family":"Sharpe","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5302-7950","authenticated-orcid":false,"given":"Jayme R","family":"Vianna","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul E","family":"Rafuse","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lesya M","family":"Shuba","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcelo T","family":"Nicolela","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7936-6907","authenticated-orcid":false,"given":"Balwantray C","family":"Chauhan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2023,10,19]]},"reference":[{"key":"2024062002150804000_108.7.978.1","doi-asserted-by":"crossref","DOI":"10.1038\/srep42201","article-title":"Detailed vascular anatomy of the human retina by projection-resolved optical coherence tomography angiography","volume":"7","author":"Campbell","year":"2017","journal-title":"Sci Rep"},{"key":"2024062002150804000_108.7.978.2","doi-asserted-by":"crossref","DOI":"10.1186\/s40942-015-0005-8","article-title":"A review of optical coherence tomography angiography (OCTA)","volume":"1","author":"de Carlo","year":"2015","journal-title":"Int J Retina Vitreous"},{"key":"2024062002150804000_108.7.978.3","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1001\/jamaophthalmol.2014.3616","article-title":"Retinal vascular layers imaged by fluorescein angiography and optical coherence tomography angiography","volume":"133","author":"Spaide","year":"2015","journal-title":"JAMA Ophthalmol"},{"key":"2024062002150804000_108.7.978.4","doi-asserted-by":"publisher","DOI":"10.4103\/2008-322X.180709"},{"key":"2024062002150804000_108.7.978.5","doi-asserted-by":"crossref","first-page":"4582","DOI":"10.1002\/mp.13142","article-title":"Early diabetic retinopathy diagnosis based on local retinal blood vessel analysis in optical coherence tomography angiography (OCTA) images","volume":"45","author":"Eladawi","year":"2018","journal-title":"Med Phys"},{"key":"2024062002150804000_108.7.978.6","doi-asserted-by":"publisher","DOI":"10.1364\/BOE.8.001741"},{"key":"2024062002150804000_108.7.978.7","doi-asserted-by":"crossref","first-page":"1589","DOI":"10.1016\/j.ophtha.2017.06.002","article-title":"Projection-resolved optical coherence tomography angiography of macular retinal circulation in glaucoma","volume":"124","author":"Takusagawa","year":"2017","journal-title":"Ophthalmology"},{"key":"2024062002150804000_108.7.978.8","doi-asserted-by":"publisher","DOI":"10.1136\/bjophthalmol-2020-318166"},{"key":"2024062002150804000_108.7.978.9","doi-asserted-by":"publisher","DOI":"10.1016\/j.preteyeres.2017.11.003"},{"key":"2024062002150804000_108.7.978.10","doi-asserted-by":"crossref","DOI":"10.1038\/s41598-020-72358-z","article-title":"Repeatability of binarization thresholding methods for optical coherence tomography angiography image quantification","volume":"10","author":"Mehta","year":"2020","journal-title":"Sci Rep"},{"key":"2024062002150804000_108.7.978.11","doi-asserted-by":"crossref","first-page":"CT211","DOI":"10.1167\/iovs.15-18793","article-title":"Normative data for vascular density in superficial and deep capillary plexuses of healthy adults assessed by optical coherence tomography angiography","volume":"57","author":"Coscas","year":"2016","journal-title":"Invest Ophthalmol Vis Sci"},{"key":"2024062002150804000_108.7.978.12","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1001\/jamaophthalmol.2017.0149","article-title":"Consensus on optical coherence Tomographic angiography nomenclature","volume":"135","author":"Fawzi","year":"2017","journal-title":"JAMA Ophthalmol"},{"key":"2024062002150804000_108.7.978.13","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pone.0170476","article-title":"Retinal vessel density from optical coherence tomography angiography to differentiate early glaucoma, pre-perimetric glaucoma and normal eyes","volume":"12","author":"Akil","year":"2017","journal-title":"PLoS ONE"},{"key":"2024062002150804000_108.7.978.14","doi-asserted-by":"crossref","first-page":"851","DOI":"10.1097\/IJG.0000000000000768","article-title":"Reproducibility of optical coherence tomography angiography macular and optic nerve head vascular density in glaucoma and healthy eyes","volume":"26","author":"Manalastas","year":"2017","journal-title":"J Glaucoma"},{"key":"2024062002150804000_108.7.978.15","doi-asserted-by":"crossref","first-page":"1475","DOI":"10.1097\/IAE.0000000000001407","article-title":"Reproducibility of vessel density measurement with optical coherence tomography angiography in eyes with and without retinopathy","volume":"37","author":"You","year":"2017","journal-title":"Retina"},{"key":"2024062002150804000_108.7.978.16","doi-asserted-by":"crossref","first-page":"2102","DOI":"10.1097\/IAE.0000000000001458","article-title":"Variability in foveal avascular zone and capillary density using optical coherence tomography angiography machines in healthy eyes","volume":"37","author":"Magrath","year":"2017","journal-title":"Retina"},{"key":"2024062002150804000_108.7.978.17","doi-asserted-by":"crossref","DOI":"10.1038\/s41598-018-28994-7","article-title":"Intrasession and between-visit variability of retinal vessel density values measured with OCT angiography in diabetic patients","volume":"8","author":"Czak\u00f3","year":"2018","journal-title":"Sci Rep"},{"key":"2024062002150804000_108.7.978.18","doi-asserted-by":"crossref","first-page":"1068","DOI":"10.1080\/02713683.2022.2061004","article-title":"Intrasession repeatability and intersession reproducibility of macular vessel parameters on optical coherence tomography angiography in Glaucomatous and non-Glaucomatous eyes","volume":"47","author":"Vorperian","year":"2022","journal-title":"Curr Eye Res"},{"key":"2024062002150804000_108.7.978.19","doi-asserted-by":"publisher","DOI":"10.1136\/bjophthalmol-2018-313461"},{"key":"2024062002150804000_108.7.978.20","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1016\/j.ajo.2017.11.011","article-title":"Reproducibility of vessel density, fractal dimension, and foveal avascular zone using 7 different optical coherence tomography angiography devices","volume":"186","author":"Corvi","year":"2018","journal-title":"Am J Ophthalmol"},{"key":"2024062002150804000_108.7.978.21","doi-asserted-by":"publisher","DOI":"10.1007\/s00417-018-4053-2"},{"key":"2024062002150804000_108.7.978.22","doi-asserted-by":"crossref","first-page":"39","DOI":"10.1016\/j.ajo.2020.08.031","article-title":"Discrepancy in loss of macular perfusion density and ganglion cell layer thickness in early glaucoma","volume":"221","author":"Hirasawa","year":"2021","journal-title":"Am J Ophthalmol"},{"key":"2024062002150804000_108.7.978.23","doi-asserted-by":"crossref","first-page":"433","DOI":"10.1016\/j.ajo.2019.06.013","article-title":"Reply to correspondence: impact of binarization thresholding and brightness\/contrast adjustment methodology on optical coherence tomography angiography image quantification","volume":"207","author":"Mehta","year":"2019","journal-title":"Am J Ophthalmol"},{"key":"2024062002150804000_108.7.978.24","doi-asserted-by":"crossref","first-page":"317","DOI":"10.1016\/j.jcjo.2020.03.011","article-title":"Thresholding strategies to measure vessel density by optical coherence tomography angiography","volume":"55","author":"Corvi","year":"2020","journal-title":"Canadian Journal of Ophthalmology"},{"key":"2024062002150804000_108.7.978.25","doi-asserted-by":"publisher","DOI":"10.1136\/bjophthalmol-2020-318677"},{"key":"2024062002150804000_108.7.978.26","doi-asserted-by":"publisher","DOI":"10.1136\/bjophthalmol-2019-315592"},{"key":"2024062002150804000_108.7.978.27","doi-asserted-by":"crossref","first-page":"697","DOI":"10.1097\/IJG.0000000000001857","article-title":"Predictors of peripapillary and macular optical microangiography measurements in healthy eyes","volume":"30","author":"Bansal","year":"2021","journal-title":"J Glaucoma"},{"key":"2024062002150804000_108.7.978.28","doi-asserted-by":"crossref","first-page":"399","DOI":"10.1097\/01.ijg.0000212261.12112.99","article-title":"Learning effect of short-wavelength automated perimetry in patients with ocular hypertension","volume":"15","author":"Rossetti","year":"2006","journal-title":"J Glaucoma"},{"key":"2024062002150804000_108.7.978.29","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1590\/S0004-27492007000100017","article-title":"Flicker perimetry in healthy subjects: influence of age and gender, learning effect and short-term fluctuation","volume":"70","author":"Bernardi","year":"2007","journal-title":"Arq Bras Oftalmol"},{"key":"2024062002150804000_108.7.978.30","doi-asserted-by":"crossref","first-page":"851","DOI":"10.1038\/eye.2009.210","article-title":"Learning effect in visual field testing of healthy subjects using humphrey matrix frequency doubling technology Perimetry","volume":"24","author":"Pierre-Filho","year":"2010","journal-title":"Eye"},{"key":"2024062002150804000_108.7.978.31","doi-asserted-by":"publisher","DOI":"10.1167\/iovs.06-0096"},{"key":"2024062002150804000_108.7.978.32","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1167\/tvst.4.5.7","article-title":"Effect of signal intensity on measurement of ganglion cell complex and retinal nerve fiber layer scans in fourier-domain optical coherence tomography","volume":"4","author":"Zhang","year":"2015","journal-title":"Trans Vis Sci Tech"},{"key":"2024062002150804000_108.7.978.33","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1016\/j.ajo.2018.12.007","article-title":"Parapapillary deep-layer microvasculature dropout and visual field progression in glaucoma","volume":"200","author":"Kwon","year":"2019","journal-title":"Am J Ophthalmol"},{"key":"2024062002150804000_108.7.978.34","doi-asserted-by":"crossref","first-page":"4614","DOI":"10.1167\/iovs.18-25038","article-title":"Microvascular changes in peripapillary and optic nerve head tissues after trabeculectomy in primary open-angle glaucoma","volume":"59","author":"Kim","year":"2018","journal-title":"Invest Ophthalmol Vis Sci"},{"key":"2024062002150804000_108.7.978.35","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajo.2017.07.011"},{"key":"2024062002150804000_108.7.978.36","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1016\/j.ajo.2021.01.015","article-title":"Association between progressive retinal capillary density loss and visual field progression in open-angle glaucoma patients according to disease stage","volume":"226","author":"Shin","year":"2021","journal-title":"Am J Ophthalmol"}],"container-title":["British Journal of Ophthalmology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bjo-2022-322979","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,6,20]],"date-time":"2024-06-20T18:28:40Z","timestamp":1718908120000},"score":1,"resource":{"primary":{"URL":"https:\/\/bjo.bmj.com\/lookup\/doi\/10.1136\/bjo-2022-322979"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,10,19]]},"references-count":36,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2024,6,20]]},"published-print":{"date-parts":[[2024,7]]}},"alternative-id":["10.1136\/bjo-2022-322979"],"URL":"https:\/\/doi.org\/10.1136\/bjo-2022-322979","relation":{},"ISSN":["0007-1161","1468-2079"],"issn-type":[{"value":"0007-1161","type":"print"},{"value":"1468-2079","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,10,19]]}}}