Abstract
Purpose :
Mitochondrial dysfunction is considered to play a crucial role in the pathophysiology of diabetic retinopathy (DR). However, in vivo confirmation is lacking. Previous pilot studies demonstrated that mitochondrial dysfunction can be non-invasively assessed by measuring retinal flavoprotein fluorescence (FPF), a mitochondrial dysfunction biomarker. The purpose of this study was to assess whether mitochondrial dysfunction by measuring FPF is correlated to the level of diabetic retinopathy.
Methods :
An IRB approved retrospective chart review was conducted on patients with FPF imaging without diabetes, with diabetes but without retinopathy, and with diabetic retinopathy. The level of FPF was measured with modified EIDON confocal scanner (Centervue, Padova, Italy) by inserting 458±2nm excitation and 535 nm emission filters, detecting a fluorescence spectrum from 520 to 540 nm. Patients were above the age of 18, had at least one healthy eye with no ocular pathology, and a phakic lens status. Patients without diabetic retinopathy (DM) (10 eyes, mean age 67, range 65-69), diabetic patients with non-proliferative diabetic retinopathy (NPDR) (2 eyes, mean age 68, range 68-69), and age-matched controls (8 eyes, mean age 68, range 66-70) were enrolled within the study. Images were obtained over 23° rectangular field auto-focused at the macula. Average FPF intensity and curve width was calculated with built-in software. One-way ANOVA was used to assess statistical significance.
Results :
Average FPF intensity was significantly higher in NPDR eyes compared to control eyes (101±8.49 vs 76.75±6.56, p=0.003) and to DM eyes (101±8.49 vs 80.9±10.62, p=0.01). No significant statistical difference was found between DM eyes and age-matched controls (80.9±10.62 vs 76.75±6.56, p=0.347). FPF curve width was not significantly different in NPDR compared to controls (18±0 vs 18.63±3.02 p=0.85) and to DM eyes (18±0 vs 20.2±4.98 p=0.49). The FPF curve width of DM eyes and age-matched controls showed no significant difference (20.2±4.98 vs 18.63±3.02 p=0.43).
Conclusions :
These results demonstrate that non-invasive measurement of mitochondrial dysfunction is correlated to the level of diabetic retinopathy. Detection of an increase in FPF intensity from individual basal levels in DM patients can potentially become a crucial tool to identify this functional alteration and provide an early diagnosis without waiting for structural damage.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.