Directional Spread in Geographic Atrophy

Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in industrial countries. In the late stages of the disease, neovascular changes or the development of geographic atrophy (GA) may induce severe visual loss. GA is characterized by the development of areas of outer retinal atrophy with continuous spread over time that is corresponded to an visual field defect for the patient. The pathogenesis is still incompletely understood. Despite the break-through in the treatment of neovascular AMD by intravitreally administrated vascular endothelial growths factor (VEGF) inhibitors, there is yet no treatment available to slow down or halt the disease process in GA. We and others have demonstrated that the total GA area progression shows large differences between patients. Potential factors influencing differential progression have been intensely studied: While neither systemic nor genetic factors have been shown to influence GA progression, ocular characteristics such as GA baseline size or phenotypic features of fundus autofluorescence (FAF) abnormalities have been identified as risk characteristics for increased GA progression. While these previous studies have mainly focused on the characterization of total GA area progression, topographic directional spread has not been analyzed and relevant predictive markers are yet unknown. There may be large differences in the local GA progression. The primary objective of this study is to identify specific characteristics, for the local GA progression. The knowledge of such risk factors may help to better understand the pathogenesis of GA. The identification of predictive markers will allow for better prognostic assessment of the individual disease process. The DSGA study is the extension trial of the FAM (Fundus Autofluorescence in Age-related Macular Degeneration) study (NCT00393692).