Fundus autofluorescence imaging in age-related macular degeneration and geographic atrophy

The traditional method for documenting and quantifying geographic atrophy (GA) is color photography. This method has been shown to be reproducible in several clinical trials, including the Age-related Eye Disease Study (AREDS) and the natural progression of GA studies by Sunness et al. (AREDS No. 6, Am J Ophthalmol 132(5):668-681, 2001; Sunness et al., Invest Ophthalmol Vis Sci 40(8):1761-1769, 1999). Nevertheless, it can be difficult to distinguish between dead/nonfunctioning retinal pigment epithelium (RPE), living but depigmented RPE (RPE often release melanin granules upon injury), and yellowish coloration caused by large drusen or calcified regressed drusen. Two imaging technologies that seem promising are fundus autofluorescence (FAF) and spectral domain (high resolution) optical coherence tomography (SDOCT). Here we provide an overview of FAF imaging in the setting of age-related macular degeneration (AMD) and GA.