A total of 407 images of different eyes with nonadvanced stages of AMD (i.e., stages 1, 2, and 3 according to the criteria shown in
Table 1), with sufficient grading quality for human graders, was selected in consecutive fashion from the European Genetic Database (EUGENDA,
http://www.eugenda.org), a large multicenter database for clinical and molecular analysis of AMD.
33,34 For each subject, images of both eyes were eligible for inclusion, but we did not select multiple images of the same eye. Images with presence of reticular pseudodrusen were excluded from analyses. Number of drusen, age, or ethnicity was not taken into account for the selection of data. Written informed consent was obtained before enrolling patients in EUGENDA. The study was performed according to the tenets set forth in the Declaration of Helsinki, and Investigational Review Board approval was obtained.
Digital nonstereoscopic color fundus photographs were acquired with a TRC 501X model digital fundus camera at 50° (Topcon Corp., Tokyo, Japan) or with a CR-DGi model non-mydriatic retinal camera at 45° (Canon, Inc., Tokyo, Japan), and pupil dilation was achieved with topical 1.0% tropicamide and 2.5% phenylephrine. All images were macula-centered. Image size varied from 1360 × 1024 to 3504 × 2336 pixels. Before analysis, images were resized in a preprocessing step to have a field of view with a standardized diameter of 630 pixels independently of the image resolution. The data were divided randomly into two sets: set A, consisting of 52 images, for the evaluation of automatic drusen quantification, and set B, consisting of 355 images, for the evaluation of automatic risk assessment. Images from the same patients were kept in the same set.