Progression of age-related geographic atrophy: role of the fellow eye.

PURPOSE. To evaluate the role of fellow eye status in determining progression of geographic atrophy (GA) in patients with age-related macular degeneration (AMD). METHODS. A total of 300 eyes with GA of 193 patients from the prospective, longitudinal, natural history FAM Study were classified into three groups according to the AMD manifestation in the fellow eye at baseline examination: (1) bilateral GA, (2) early/intermediate AMD, and (3) exudative AMD. GA areas were quantified based on fundus autofluorescence images using a semiautomated image-processing method, and progression rates (PR) were estimated using two-level, linear, mixed-effects models. RESULTS. Crude GA-PR in the bilateral GA group (mean, 1.64 mm(2)/y; 95% CI, 1.478-1.803) was significantly higher than in the fellow eye early/intermediate group (0.74 mm(2)/y, 0.146-1.342). Although there was a significant difference in baseline GA size (P = 0.0013, t-test), and there was a significant increase in GA-PR by 0.11 mm(2)/y (0.05-0.17) per 1 disc area (DA; 2.54 mm(2)), an additional mean change of -0.79 (-1.43 to -0.15) was given to the PR beside the effect of baseline GA size. However, this difference was only significant when GA size was ≥1 DA at baseline with a GA-PR of 1.70 mm(2)/y (1.54-1.85) in the bilateral and 0.95 mm(2)/y (0.37-1.54) in the early/intermediate group. There was no significant difference in PR compared with that in the fellow eye exudative group. CONCLUSIONS. The results indicate that the AMD manifestation of the fellow eye at baseline serves as an indicator for disease progression in eyes with GA ≥ 1 DA. Predictive characteristics not only contribute to the understanding of pathophysiological mechanisms, but also are useful for the design of future interventional trials in GA patients.

Combined confocal scanning laser ophthalmoscopy and spectral-domain optical coherence tomography imaging of reticular drusen associated with age-related macular degeneration.

PURPOSE: To determine microstructural retinal alterations associated with reticular drusen in patients with age-related macular degeneration (AMD) using high-resolution in vivo imaging techniques. DESIGN: Retrospective case series. PARTICIPANTS: A total of 116 eyes of 78 AMD patients with reticular drusen were examined. METHODS: Simultaneous spectral-domain optical coherence tomography (SD OCT; 870 nm, 40,000 A-scans/sec) and near-infrared confocal scanning laser ophthalmoscopy (cSLO; 830 nm) were performed using a combined imaging instrument (Spectralis HRA+OCT, Heidelberg Engineering, Heidelberg, Germany). Individual anatomic layers in SD OCT were evaluated and correlated to en face cSLO fundus imaging. MAIN OUTCOME MEASURES: Description of corresponding structural changes in areas of reticular drusen. RESULTS: Reticular drusen appeared as an interlacing network of round or oval irregularities by near-infrared cSLO reflectance imaging. On SD OCT, reticular drusen corresponded to marked changes at a level anterior to the retinal pigment epithelium (RPE) and Bruch's membrane complex to the interface of inner and outer photoreceptor segment layer (IPRL). Individual reticular drusen correlated to focal elevations of the IPRL, accumulation of highly reflective material below the IPRL, and an increased distance between the IPRL and RPE. CONCLUSIONS: The findings indicate that the morphologic substrate of reticular drusen is the accumulation of highly reflective material within outer retinal layers anterior to the RPE. This is in contrast to previous assumptions pointing toward a localization of abnormal material at the level of the inner choroid. Although the origin of the material is unknown, the results may indicate a role for primary abnormalities in the neurosensory retina. Because reticular drusen represent high-risk markers for the progression of AMD, their ready identification is relevant both for natural history studies as well as for interventional trials.