TY - JOUR T1 - Precise montaging and metric quantification of retinal surface area from ultra-widefield fundus photography and fluorescein angiography JF - Ophthalmic Surg Lasers Imaging Retina Y1 - 2014 A1 - Croft, D.E. A1 - van Hemert, J. A1 - Wykoff, C.C. A1 - Clifton, D. A1 - Verhoek, M. A1 - Fleming, A. A1 - Brown, D.M. KW - medical KW - retinal imaging AB - BACKGROUND AND OBJECTIVE: Accurate quantification of retinal surface area from ultra-widefield (UWF) images is challenging due to warping produced when the retina is projected onto a two-dimensional plane for analysis. By accounting for this, the authors sought to precisely montage and accurately quantify retinal surface area in square millimeters. PATIENTS AND METHODS: Montages were created using Optos 200Tx (Optos, Dunfermline, U.K.) images taken at different gaze angles. A transformation projected the images to their correct location on a three-dimensional model. Area was quantified with spherical trigonometry. Warping, precision, and accuracy were assessed. RESULTS: Uncorrected, posterior pixels represented up to 79% greater surface area than peripheral pixels. Assessing precision, a standard region was quantified across 10 montages of the same eye (RSD: 0.7%; mean: 408.97 mm(2); range: 405.34-413.87 mm(2)). Assessing accuracy, 50 patients' disc areas were quantified (mean: 2.21 mm(2); SE: 0.06 mm(2)), and the results fell within the normative range. CONCLUSION: By accounting for warping inherent in UWF images, precise montaging and accurate quantification of retinal surface area in square millimeters were achieved. [Ophthalmic Surg Lasers Imaging Retina. 2014;45:312-317.]. VL - 45 ER -