The time pattern of bilateral exudative age-related macular degeneration

Purpose: To study time patterns in bilateral exudative age-related macular degeneration (AMD) and the pattern of drusen before and after the onset of exudative AMD. Material and Methods: Out of 2220 individuals in the Icelandic genetic study of AMD, 151 had bilateral exudative AMD. We searched for previous records in the Icelandic University Retina Unit. For the 65 patients with a fluorescein angiography record of both eyes, we established the time between the onset of disease in each eye. For the 53 patients with colour fundus photographs of the latter eye taken prior to the occurrence of exudative disease, we graded the drusen before and after the onset of exudative AMD in the second eye. Results: The time interval between the onset of exudative AMD in the first and second eyes was 2.5 years (95% CI: 1.8-3.2; n = 65) and the median was 1.8 years. In 82% of cases the second eye was affected within 4 years. Soft drusen in the macula were found in 95% of eyes that later developed exudative disease (n = 53). Soft and hard drusen decreased in number in the central macula following the development of exudative disease. Conclusions: Bilateral exudative AMD develops within a few years in both eyes. Drusen are less visible following the onset of exudative AMD in the second eye.