Quantitative autofluorescence in retinal disease

Fundus autofluorescence (AF) is a retinal imaging modality based on the emission of light by the retina after stimulation at specific wavelengths, either 488 nm (blue autofluorescence, BAF) or 787 nm (near-infrared autofluorescence IRAF). The objective of this work was to describe and determine the feasibility of a methodology for quantitative AF visualization. Based on relative, normalized, gray intensity measures along concentric semi-circles in the nasal and temporal sides of the macula, it provided a combined graphical representation of quantitative BAF and IRAF curves. This method was applied to 8 healthy subjects and 9 cases of achromatopsia, a stationary congenital syndrome of cone photoreceptor dysfunction. Quantitative autofluorescence curves clearly identified a normal pattern in healthy subjects and two different abnormal patterns among the achromatopsia patients, that correlated to existing disease classifications based on retinal morphology assessed by optical coherence tomography.