Correlations between Optical Coherence Tomography Angiography Findings and Multifocal Electroretinogram Parameters in Diabetic Retinopathy Patients

Abstract

Purpose : To assess the morphological and functional changes of macula in subjects with diabetic retinopathy using optical coherence tomography angiography (OCT-A) and multifocal electroretinography (mfERG), and to investigate the correlations between OCT-A and mf ERG.

Methods : Ninety eight eyes of 98 patients were enrolled on this study. OCT-A and mfERG were performed on 32 eyes with non-proliferative diabetic retinopathy (NPDR group), 33 eyes with proliferative diabetic retinopathy (PDR group), and 33 normal controls. The area and radius of foveal avascular zone (FAZ) were measured, and vessel density (VD) and perfusion of superficial and deep capillary plexus (SPC, DPC) under ETDRS grid were also estimated using OCT-A. The averaged N1 and P1 amplitudes and implicit times in the Ring 1 and 2 were calculated on mfERG recordings. The correlations between OCT-A results and mfERG parameters were analyzed in groups with NPDR, PDR, and normal controls.

Results : The mean FAZ areas were 0.38±0.10 mm² in normal controls, 0.33±0.15 mm² in NPDR group, and 0.26±0.18 mm² in PDR group, respectively. Central VD and central DPC were significantly decreased with step-wise pattern as the stage of diabetic retinopathy progresses. The mean amplitudes of N1 and P1 from Ring 1 were reduced significantly in NPDR and PDR groups compared with normal controls. VDs and perfusion parameters showed significant correlations with P1 amplitudes according to severity of diabetic retinopathy, however, FAZ area revealed no apparent correlations with mfERG results.

Conclusions : VDs and perfusion parameters were decreased in eyes with diabetic retinopathy compared to normal controls, and mfERG responses were also reduced in diabetic retinopathy with step-wise pattern. VDs and perfusion rates of OCT-A seemed to have more correlations with mfERG results than the size of FAZ. Further evaluation is needed to assess these results.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.