Abstract
Purpose :
Oxidative stress and subsequent damage to retinal mitochondria is thought to play a key role in the pathogenesis of several retinal diseases including age-related macular degeneration (AMD). When oxidized, retinal mitochondrial flavoproteins auto-fluoresce green light when excited by a particular wavelength of blue light. This emitted flavoprotein fluorescence (FPF) can be measured and used as a quantifiable marker for oxidative damage-induced mitochondrial dysfunction. This study aims to assess FPF in a sample of AMD patients grouped by stage of disease progression.
Methods :
This study was a retrospective chart review of patients diagnosed with early, intermediate, or advanced non-exudative AMD or neovascular AMD between 2012-2019 based on AREDS criteria. The comparison group included retinal images from healthy age-matched controls. Patients with comorbid glaucoma, ocular hypertension, concomitant retinopathy or uveitis, history of retinal detachment, history of cataract surgery, retinal surgery within three months, fluorescein angiogram prior to imaging, or pseudophakic lens were excluded. For each patient image, FPF score (i.e., intensity) and curve width (i.e., heterogeneity) were recorded using the OcuMet Beacon (OcuSciences, Ann Arbor, MI).
Results :
The final analysis included 369 images. The multivariable regression included early, intermediate, and advanced non-exudative AMD and neovascular AMD as well as age, smoking status, gender, ethnicity, and eye location. Intermediate and advanced non-exudative AMD and neovascular AMD were significant predictors of increased FPF score intensity (13.86, CI 8.46–19.25, p < 0.001; 30.85, CI 17.86–43.83, p < 0.001; 17.79, CI 11.91–23.67, p < 0.001 respectively), but early non-exudative AMD was not (-3.83, CI -12.82–5.16, p = 0.40). Early, intermediate, and advanced non-exudative AMD and neovascular AMD were significant predictors of increased FPF score heterogeneity (0.39, CI 0.17–0.60, p < 0.001; 0.43, CI 0.31–0.56, p < 0.001; 0.83, CI 0.52–1.13, p < 0.001; 0.69, CI 0.55–0.83, p < 0.001, respectively)
Conclusions :
Non-exudative and neovascular age-related macular degeneration are associated with increased retinal mitochondrial oxidative stress as evidenced by increased intensity and heterogeneity of flavoprotein fluorescence in patients with this disease.
This is a 2021 ARVO Annual Meeting abstract.