Abstract
Abstract: :
Purpose:Electroretinographic (ERG) abnormalities are well documented in non-proliferative diabetic retinopathy (NPDR) and are exaggerated in the presence of clinically significant macular edema (CSME).The aim of this study was to evaluate flash and pattern ERG (PERG) together with pattern visual evoked potentials (VEP) and echographic measurement of optic nerve diameter (OND) and inner pial reflectivity (IPR) in patients with NPDR with and without CSME. Methods:Thirty-eight patients with NPDR underwent ERG, PERG, VEP and echography. In 50 eyes, there was no CSME while in the remaining 26 eyes, NPDR was associated with CSME. The results of the diabetic patients were compared to those of laboratory normals. Results:In the group with NPDR without CSME, 28% of eyes had abnormal ERG b wave, 28% reduced PERG, 22% decreased photoreceptor sensitivity, 62% reduced oscillatory potentials, 36% abnormal VEP and 52% reduced OND or increased IPR.In the group with NPDR and CSME, 62% of eyes had abnormal ERG b wave, 52% reduced PERG, 42% decreased photoreceptor sensitivty, 87% reduced oscillatory potentials, 57% abnormal VEP and 48% reduced OND or increased IPR. Conclusion:The incidence of ERG, PERG and photoreceptor sensitivity abnormalities was higher in eyes with CSME as compared to eyes without CSME. These findings suggest that patients with CSME exhibit widespread retinal damage involving both outer and inner retinal layers. An interesting finding was the presence of subclinical optic nerve abnormalities, as identified echograohically, in 52% of eyes without CSME and in 48% of eyes with CSME.
Keywords: 353 clinical (human) or epidemiologic studies: outcomes/complications • 388 diabetic retinopathy • 395 electroretinography: clinical