Fundus Autofluorescence

Abstract

Fundus Autofluorescence (FAF) is a unique in vivo method of fundus imaging. Although it has been an area of active research over the last half a century, its only in the past decade that major advances have been made in its clinical application. The imaging has its basis in the mapping of normal and abnormal fluorophores in various retinal conditions mainly lipofuschin. Recording of FAF is relatively easily accomplished, requires little time and is non-invasive. FAF signals are emitted across a broad wavelength spectrum. FAF imaging aids in identification and early detection of many retinal conditions often before changes can be picked up on other investigative modalities. FAF can assist in tracking temporal changes in fundus lipofuschin accumulation; detect pre clinical stage of fundus disorders related to lipofuschin, aid differential diagnoses based on different lipofuschin accumulation patterns and also in assessing risk factors that determine lipofuschin accumulation. FAF can also predict progression in various degenerative and age related retinal disorders before actual functional deficit occurs. In this review we shall discuss the principle and techniques of acquiring an FAF image. We shall describe a normal FAF picture with its basis and review various FAF features of various fundus pathologies. Many vitreo retinal diseases like age related macular degeneration, idiopathic macular telangiectasia, choroidal neovascular membranes, central serous chorioretinopathy among others have different autofluorescence patterns which will be discussed in this review.