Spectrally Resolved (Colour-Coded) Fundus Autofluorescence Using the EIDON System in Vitreoretinal Lymphoma

INTRODUCTION: This study evaluates colour-coded fundus autofluorescence (FAF) in vitreoretinal lymphoma (VRL), which still represents a diagnostic challenge because of the variety of ocular manifestations and difficulties in obtaining a definite diagnosis. METHODS: Retrospective cross-sectional analysis of consecutive patients with VRL studied with colour-coded FAF. For comparative analysis, the patients also underwent conventional blue and green fundus FAF. Detection and appearance of typical VRL lesions in macular and extramacular locations on colour-coded FAF were studied and compared with other imaging techniques, including optical coherence tomography. RESULTS: We evaluated 20 eyes from 10 patients affected by VRL. The agreement among readers on the presence of VRL lesions using colour-coded FAF was excellent. Lesion-specific comparative analysis showed that retinitis-like lesions were identified in 2/2 eyes using colour-coded FAF versus 0/2 eyes using blue FAF and green FAF, while lymphomatous retinal pigment epithelium (RPE) detachments were detected in 4/4 eyes using colour-coded FAF versus 1/4 eyes using blue FAF and green FAF. The classic granular appearance was similarly detected in 13/13 eyes across all FAF modalities. Comparative analysis revealed that colour-coded FAF appeared to better delineate retinitis-like lesions and lymphomatous RPE detachments than other types of FAF. Conversely, green FAF was more informative within the macula, while colour-coded FAF was also able to detect minor fluorophores and showed RPE atrophic areas, sub-RPE deposits, and perivascular infiltrates. CONCLUSION: Colour-coded FAF can recognize the classic features of VRL. As a complementary imaging modality, colour-coded FAF may facilitate the recognition of retinitis-like lesions, lymphomatous retinal pigment epithelium detachments, and minor fluorophores compared with other FAF types.