Fundus Auto fluorescence (FAF)
• Fundus Autofluorescence (FAF or AF) was introduced in Retina Revealed #42 as a novel, non-invasive imaging procedure that often yields abnormalities that are invisible to ophthalmoscopy and standard color fundus photography.
• Normal AF appears as a glow of the entire retinal pigment epithelium in contrast to the disc and retina vessels which appear as nearly black.
• Hyper AF, due to the accumulation of the aging pigment lipofuscin, represents RPE dysfunction, stress or simply sick RPE cells.
• Hypo AF indicates that viable RPE cells have been lost and suggests that the overlying photoreceptors are similarly lost.
• The first case in this series is unilateral so that a comparison of normal vs abnormal AF is readily appreciated.
• The second case could not be dilated because of very narrow angles in each eye and demonstrates that 200 degree AF images are obtainable without pupillary dilation.
• The last several cases document the extraordinary variability of retinal degenerations as revealed by full field AF.