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  - 

TY  - JOUR
T1  - Quantification of Ultra-Widefield Retinal Images
JF  - Retina Today
Y1  - 2014
A1  - D.E. Croft
A1  - C.C. Wykoff
A1  - D.M. Brown
A1  - van Hemert, J.
A1  - M. Verhoek
KW  - medical
KW  - retinal imaging
AB  - Advances in imaging periodically lead to dramatic changes in the diagnosis, management, and study of retinal disease. For example, the innovation and wide-spread application of fluorescein angiography and optical coherence tomography (OCT) have had tremendous impact on the management of retinal disorders.1,2 Recently, ultra-widefield (UWF) imaging has opened a new window into the retina, allowing the capture of greater than 80% of the fundus with a single shot.3 With montaging, much of the remaining retinal surface area can be captured.4,5 However, to maximize the potential of these new modalities, accurate quantification of the pathology they capture is critical.
UR  - http://www.bmctoday.net/retinatoday/pdfs/0514RT_imaging_Croft.pdf
ER  -