Fundus autofluorescence and retinal sensitivity in fellow eyes of age-related macular degeneration in Japan

Abstract

Purpose Abnormal fundus autofluorescence (FAF) potentially precedes onset of late age-related macular degeneration (AMD) in Caucasian patients. Many differences exist between Asian and Caucasian patients regarding AMD types and severity, gender, and genetic backgrounds. We investigated the characteristics of abnormal FAF and retinal sensitivity in the fellow eyes of Japanese patients with unilateral neovascular AMD. Methods Sixty-six patients with unilateral neovascular AMD and abnormal FAF in the fellow eye were enrolled in this multicenter, prospective, observational study. The best-corrected visual acuity, fundus photographs, FAF images, and retinal sensitivity on microperimetry were measured periodically for 12 months. The FAF images were classified into eight patterns based on the International Fundus Autofluorescence Classification Group. The points measured by microperimetry were superimposed onto the FAF images and fundus photographs and classified as “within,” “close,” and “distant,” based on the distance from the abnormal FAF and other findings. The relationship between the location of the baseline abnormal FAF and retinal sensitivity was investigated. Results In Japanese patients, patchy (33.3%) and focally increased (30.3%) patterns predominated in the abnormal FAF. Intermediate-to-large drusen was associated predominantly with hyperfluorescence and hypofluorescence. Neovascular AMD developed within 1 year in six (9.1%) eyes, the mean baseline retinal sensitivity of which was 12.8 ± 4.7 dB, significantly (p<0.002) lower than the other eyes. In 44 of the other 60 eyes, microperimetry was measurable at baseline and month 12 and the mean retinal sensitivity improved significantly from 13.5 ± 4.4 to 13.9 ± 4.8 dB (p<0.001), possibly associated with lifestyle changes (e.g., smoking cessation, antioxidant and zinc supplementation). The mean retinal sensitivities of points within and close to the abnormal FAF were 9.9 and 11.7 dB, respectively, which were significantly lower than the 14.0 dB of the points distant from the abnormal FAF. Conclusion In Japanese patients, patchy and focally increased patterns predominated in the abnormal FAF. The retinal sensitivity was lower close to/within the abnormal FAF. FAF and microperimetry are useful to assess macular function before development of neovascular AMD or geographic atrophy.

Five-year follow-up of fundus autofluorescence and retinal sensitivity in the fellow eye in exudative age-related macular degeneration in Japan

“…The major exclusion criteria were the presence of exudative findings in the fellow eyes, including CNV, hemorrhage, serous RPE detachment, serous retinal detachment, and hard exudates, diabetic retinopathy, uveitis, high myopia (less than -8.0 diopters), retinal vein occlusion, hazy media interfering with fundus examinations, or a history of laser photocoagulation. In this study, the fellow eyes had drusen and/or pigmentary abnormalities (n = 65) and extrafoveal geographic atrophy (n = 1) at initial visit [9].…”

“…Our previous study demonstrated that the prevalence of abnormal FAF patterns and clinical features of late AMD were different among races [9]. The association between microperimetry and FAF imaging has been reported with a shortduration follow-up [9,26]. We previously reported the one-year results [9].…”

“…The association between microperimetry and FAF imaging has been reported with a shortduration follow-up [9,26]. We previously reported the one-year results [9]. However, longduration follow-ups and the clinical course of retinal sensitivity and FAF pattern changes have not been reported.…”

“…We adopted the same parameters as previously reported, a customized radial grid of 45 stimuli covering the central 12 degrees, stimuli size Goldman III with a PLOS ONE presentation time of 200 ms, and 0-20 dB stimulus light intensity of 4-asb white light as the background. A 4-2 stimuli strategy was used [9].…”

“…Previous studies reported that the fellow eye in unilateral exudative AMD represents a risk factor for the development of choroidal neovascularization (CNV) or GA involving the center of the macula [4][5][6]. In intermediate-to-late AMD, patients are recommended to quit smoking [7,8] and maintain a balanced and healthy diet [9]. Other risk factors such as hypertension, atherosclerosis, overweight [10], and genetic factors [11] are also reported.…”