![]() In a healthy retina, the posterior pole will have a diffuse gray appearance-a mildly hyper-fluorescent signal due to normal levels of lipofuscin in RPE cells. The intensity of the FAF signal corresponds to the accumulation or absence/reduction of lipofuscin and is compared to the surrounding retina. The images produced are similar in appearance to those of fluorescein angiography images however, unlike FA, FAF is not dependent on circulation as is fluorescein angiography. 1-3,5,9 This lets us visualize RPE changes that are affected by lipofuscin. ![]() FAF allows us to take advantage of the autofluorescent properties of lipofuscin when exposed to short-to-medium wavelengths of light (short 500nm to medium 750nm). 1 This makes the presence of lipofuscin a potential early indicator of degenerative retinal diseases. While this occurs naturally with age, excess accumulation is considered pathologic and may occur with RPE cell dysfunction or abnormal metabolic load on the RPE. Lipofuscin will accumulate in the RPE when its ability to break down pigmented outer segments of photoreceptors is compromised. Lipofuscin, a byproduct of phagocytosed photoreceptor outer segments, is found in a number of aging and diseased tissues, including the RPE. The retinal pigment epithelium (RPE) plays an important role in the normal functioning of the retina and is essential for vision. Although an excellent clinical tool, FAF can be used in conjunction with conventional fundus photography, optical coherence tomography (OCT), fluorescein angiography and other imaging modalities to provide an even more complete clinical picture. 1 It has also helped us understand certain pathophysiological mechanisms. Research has shown it to be effective in the early detection of retinal disease and the potential predictive makers for progression. 1 FAF provides a view of the disease processes from a metabolic perspective. Although FAF technology has been referenced in medical research for more than 40 years, advances over the last decade have made it increasingly relevant as an ophthalmic imaging technique suitable for daily practice. ![]() With its relative ease of use, noninvasive technique and ability to aid in the diagnosis and management of a variety of retinal disorders, fundus autofluorescence (FAF) has increasingly become a mainstream imaging modality.
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