Correlation Between Retinal Oscillatory Potentials and Retinal Vascular Caliber in Type 2 Diabetes
Chi D. Luu 1*,
Josh A Szental 2,
Shu-Yen Lee 3,
Raghavan Lavanya 4,
and
Tien Yin Wong 5
1 Macular Research Unit, Centre for Eye Research Australia, Level 1, 32 Gisborne Street, East Melbourne, Victoria, 3002, Australia; Visual Electrophysiology, Singapore Eye Research Institute, 11 Third Hospital Avenue, 129783, Singapore
2 Macular Research Unit, Centre for Eye Research Australia, East Melbourne, Victoria, Australia
3 Vitreo-Retina Service, Singapore National Eye Centre, Singapore, Singapore
4 Singapre National Eye Centre, Singapore, Singapore
5 , Singapore Eye Research Institute, 11 Third Hospital Avenue, Singapore; Centre for Eye Research Australia, 32 Gisborne Street, Melbourne, Victoria, 3002, Australia; Vitreo-Retina Service, Singapore National Eye Centre, Singapore, Singapore; Department of Ophthalmology, National University of Singapore, Singapore, Singapore
* To whom correspondence should be addressed. E-mail: cdlvep{at}yahoo.com.
 |
Abstract |
|---|
Purpose: To assess retinal function in Type 2 diabetics with no retinopathy and non-proliferative diabetic retinopathy (NPDR), and determine the relationship between retinal function and retinal vascular caliber.
Methods: A full-field electroretinogram (ERG) and retinal vascular caliber measurements were performed in subjects with non-proliferative diabetic retinopathy (NPDR, n=10), diabetic subjects without retinopathy (No DR, n=18) and normal control subjects (n=18). The response amplitudes and implicit times of scotopic and photopic ERG, and the retinal arteriolar and venular calibers were compared among the study groups. The relationships between ERG parameters and retinal vascular calibres were determined.
Results: There were statistically significant differences between diabetic subjects (No-DR and NPDR groups) and controls in the amplitudes and implicit times of rod-derived ERG responses, but not the cone-derived ERG responses. All the oscillatory potential (OP) components (OP1-OP4) were significantly reduced in amplitude and increased in implicit time in the No-DR and NPDR groups. No significant difference was found in any of the ERG parameters between the No-DR and NPDR groups. Of all the ERG parameters examined, only OP4 amplitude was significantly correlated with the retinal arteriolar caliber (r = -0.556, p = 0.006). None of the OP components were significantly correlated with retinal venular caliber.
Conclusions: Significant retinal dysfunction was demonstrated in all diabetic patients, even in those without clinically detectable retinopathy, with rod system being affected more than cone system. OP4 amplitude correlates with retinal arteriolar caliber in diabetic patients, suggesting a correlation between retinal neuronal dysfunction and microvasculature changes.
Key Words:
oscillatory potentials, retinal vasculature, diabetic retinopathy, electroretinography
