SPECTRAL FUNDUS AUTOFLUORESCENCE EXCITATION AND EMISSION IN ABCA4-RELATED RETINOPATHY

Abstract

To systematically and longitudinally investigate the characteristics of flecks in ABCA4-related retinopathy under different fundus autofluorescence (AF) excitation and emission spectra. A total of 132 eyes of 66 patients with ABCA4-related retinopathy were investigated using multimodal AF imaging and spectral domain optical coherence tomography. Autofluorescence imaging with blue (BAF), green (GAF), and near-infrared (NIR-AF) excitation wavelengths obtained by a confocal scanning laser ophthalmoscope was compared with AF imaging obtained by an innovative confocal light-emitting diode-based retinal imaging system (Color-AF) that allows for separation of short (green emission fluorescent component) and long (red emission fluorescent component) autofluorescence emission components. Color-AF, BAF, and GAF, overall, revealed similar presentation of hyperautofluorescent flecks. Flecks that showed predominantly red emission fluorescent component matched with hyperautofluorescent flecks in NIR-AF. Over the observation time of 5 to 14 months, flecks showed a transition in the AF emission spectrum to shorter wavelengths (red emission fluorescent component to green emission fluorescent component), associated with a progressed disruption of overlaying outer retinal bands in optical coherence tomography. Newer hyperautofluorescent flecks usually revealed predominantly red emission fluorescent component. By separation of the AF spectra, the remodeling of fluorophores and associated structural changes can be monitored over time indicating a novel and susceptible surrogate marker for disease progression and potential therapeutic effects.

Publication
Retina