Does Multifocal Electroretinogram (mfERG) Correlate with the Optical Coherence Tomography (OCT) Macular Thickness, and the Visual Acuity, in Diabetic Macular Edema (DME) Cases?

Objective: The functional deficit in diabetic macular edema, is tested by the patient s acuity. The aim of this study is to assess the credibility of the Multifocal Electro-Retinogram (mfERG), in assessing macular function, in relation to visual acuity and Optical Coherence Tomography (OCT) findings. Methods: 30 macular edema eyes of 20 Diabetic patients underwent Visual Acuity (VA) measurement, Optical Coherence Tomography (OCT), and mfERG. Data were statisctically analysed. Results: Only in one quadrant, that mfERG (P1 amplitude) was found to be related to the OCT maximum thickness. Only in markedly diminished visual acuity that mfERG (Peak p1 time) were significantly diminished in the fovea. OCT was found to be not significantly relevant to the amount of diminished visual acuity. This study showed that OCT and mfERG each alone, reflects only partially and incompletely the actual macular function. Conclusion: mfERG alone is not a good indicator of macular function in diabetic macular edema.