Feasibility of In Vivo Retinal Flavoprotein Autofluorescence Imaging in a Magnetic-Bead-Induced Rodent Glaucoma Model

Mitochondrial dysfunction and oxidative stress in retinal ganglion cells (RGCs) are critical events in the pathogenesis of glaucoma that occur prior to structural degeneration and visual field loss. Flavoprotein fluorescence (FPF) produced by oxidized mitochondrial flavoproteins offers a potential biomarker for early detection of cellular dysfunction. This study investigated the feasibility of performing FPF imaging in a rodent glaucoma model and its integration with a real-time optical coherence tomography (OCT) alignment monitor that verifies on-retina focus during fluorescence acquisition. A scanning laser ophthalmoscope-OCT system was constructed, with two photomultiplier tubes to differentiate FPF from lipofuscin autofluorescence. In the rodent glaucoma model induced by intracameral magnetic bead injection, FPF signals were detected under 450-nm excitation, while 505-nm excitation produced no signal. This proof-of-concept work demonstrates that in vivo retinal FPF imaging is feasible in this glaucoma model, which may facilitate early detection of RGC dysfunction at a cellular level.