Retro-Mode Imaging, Blue-Light Fundus Autofluorescence and Near-Infrared Fundus Autofluorescence in Retinal Dystrophies

Purpose Retinal dystrophies show a considerably wide phenotypic variability which can make the diagnosis and the clinical staging difficult. Aim of the study is to analyze the contribution of retro-mode imaging (RMI) and fundus autofluorescence to the characterization and the staging of the retinal dystrophies. Methods Eighteen patients affected by retinal dystrophies (2 patients with Best Vitelliform Macular Dystrophy (BVMD), 5 patients with autosomal recessive Stargardt Disease-Fundus Flavimaculatus (STGD1), 8 patients with Pattern Dystrophy, 2 patients with Choroideremia (CHM), and 1 patient with Benign Concentric Annular Macular Dystrophy (BCAMD) were recruited for the study. All the patients underwent a complete ophthalmological examination, including best corrected visual acuity with ETDRS charts, blue-light autofluorescence, (BL-AF), near-infrared autofluorescence (NI-AF), and RMI. Results Overall, the main feature of RMI is represented by a pseudo-3D pattern of all the lesions at the posterior pole. More specifically, any accumulation of material within the retina appear as an area of elevation with different shape and sizes, showing irregular and darker borders. BL-AF reveals the deposition of lipofuscin, whereas NIR-AF shows alterations in the melanin distribution. Conclusions There is no precise correlation among RMI, BL-AF, and NIR-AF imaging. RMI and fundus autofluorescence appear as useful tools for the identification and follow-up of retinal dystrophies. Non-invasive diagnostic tools may yield additional information in the clinical setting and the monitoring of the patients.