{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T21:55:27Z","timestamp":1785794127400,"version":"3.56.0"},"reference-count":9,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,11,5]],"date-time":"2025-11-05T00:00:00Z","timestamp":1762300800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Tomography"],"abstract":"<jats:p>Purpose: To compare retinal thickness measurements obtained with the Optos Monaco and Heidelberg Spectralis optical coherence tomography (OCT) systems across 9 Early Treatment Diabetic Retinopathy Study (ETDRS) sectors in a cohort comprising normal eyes. Methods: Paired OCT scans from 64 eyes of 32 participants with normal retinal findings were acquired on both devices. Thickness measurements were obtained for the central subfield and the inner and outer sectors of the superior, nasal, inferior, and temporal quadrants. Outcomes included mean thickness, mean interdevice difference (Heidelberg minus Monaco), Pearson correlation coefficients, and Bland\u2013Altman analyses. Scatterplots and Bland\u2013Altman plots were constructed to evaluate agreement and assess potential interchangeability. Results: The Heidelberg Spectralis yielded significantly greater retinal thickness values than the Optos Monaco in all ETDRS sectors (p &lt; 0.001), with mean differences ranging from +16.9 \u00b5m (outer superior) to +26.8 \u00b5m (inner superior). Pearson correlation coefficients indicated strong positive agreement (r \u2265 0.8) for the central subfield and most inner sectors, and moderate to strong positive agreement (r \u2265 0.5) in a single outer sector. Bland\u2013Altman analyses demonstrated a statistically significant systematic bias favoring greater measurements with Heidelberg in most quadrants, with limits of agreement indicating clinically relevant variability. Although the relative agreement was high, absolute differences limit direct interchangeability. Conclusions: Optos Monaco and Heidelberg Spectralis exhibit strong linear correlation in retinal thickness measurements but show significant systematic differences. Interchangeable use requires the application of correction factors where segmentation variability may be greater.<\/jats:p>","DOI":"10.3390\/tomography11110124","type":"journal-article","created":{"date-parts":[[2025,11,5]],"date-time":"2025-11-05T13:19:29Z","timestamp":1762348769000},"page":"124","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Comparison of Retinal Thickness Measurements Using Optos Monaco and Heidelberg Spectralis OCT Across ETDRS Sectors in Normal Eyes"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0004-9416","authenticated-orcid":false,"given":"Kakarla V.","family":"Chalam","sequence":"first","affiliation":[{"name":"Department of Ophthalmology, Loma Linda University, Loma Linda, CA 92354, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lourdes","family":"Ceja","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Loma Linda University, Loma Linda, CA 92354, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rene","family":"Obispo","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Loma Linda University, Loma Linda, CA 92354, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0596-1903","authenticated-orcid":false,"given":"Minali","family":"Prasad","sequence":"additional","affiliation":[{"name":"Chobanian & Avedisian School of Medicine, Boston University, Boston, MA 02118, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7035-8567","authenticated-orcid":false,"given":"Anny M. S.","family":"Cheng","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, University of Florida, Gainesville, FL 32605, USA"},{"name":"Department of Ophthalmology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1167\/tvst.12.7.12","article-title":"High-Resolution Optical Coherence Tomography in Healthy Individuals Provides Resolution at the Cellular and Subcellular Levels","volume":"12","author":"Reche","year":"2023","journal-title":"Transl. Vis. Sci. Technol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"218","DOI":"10.1111\/opo.12289","article-title":"The fundus photo has met its match: Optical coherence tomography and adaptive optics ophthalmoscopy are here to stay","volume":"36","author":"Morgan","year":"2016","journal-title":"Ophthalmic Physiol. Opt."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"417","DOI":"10.21037\/qims-20-1252","article-title":"Baseline retinal thickness measurements with a novel integrated imaging system (concurrent optical coherence tomography and fundus photography) positively correlates with spectralis optical coherence tomography","volume":"12","author":"Enghelberg","year":"2022","journal-title":"Quant. Imaging Med. Surg."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"549","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":"ref_5","unstructured":"(2025, November 01). Monaco. Available online: https:\/\/www.optomedica.com\/prodotti\/diagnostica\/oct\/optos-monaco\/."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Azzopardi, M., Gridhar, S., Tsika, C., Koutsocheras, G., Katzakis, M., Demir, B., Rahman, W., Heng, L.Z., Chong, Y.J., and Logeswaran, A. (2025). A Comparison of Ultra-Widefield Imaging Quality Obtained with Zeiss Clarus and Optos for Virtual Medical Retina Services. J. Clin. Med., 14.","DOI":"10.3390\/jcm14103270"},{"key":"ref_7","unstructured":"(2025, November 01). SPECTRALIS Imaging Platform Technical Specifi Cations. Heidelberg Engineering. Available online: https:\/\/business-lounge.heidelbergengineering.com\/ve\/en\/products\/spectralis\/spectralis\/downloads\/."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"100670","DOI":"10.1016\/j.xops.2024.100670","article-title":"Validation of Deep Learning-Based Automatic Retinal Layer Segmentation Algorithms for Age-Related Macular Degeneration with 2 Spectral-Domain OCT Devices","volume":"5","author":"Mukherjee","year":"2024","journal-title":"Ophthalmol. Sci."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"850","DOI":"10.1080\/08164622.2024.2438132","article-title":"Optic nerve assessment with stereo photographs and ultra-widefield scanning laser ophthalmoscope images","volume":"108","author":"Salazar","year":"2024","journal-title":"Clin. Exp. Optom."}],"container-title":["Tomography"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2379-139X\/11\/11\/124\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,11,6]],"date-time":"2025-11-06T10:12:34Z","timestamp":1762423954000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2379-139X\/11\/11\/124"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,11,5]]},"references-count":9,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2025,11]]}},"alternative-id":["tomography11110124"],"URL":"https:\/\/doi.org\/10.3390\/tomography11110124","relation":{},"ISSN":["2379-139X"],"issn-type":[{"value":"2379-139X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,11,5]]}}}