To evaluate the macular function by a multifocal electroretinogram (mfERG) in patients with diabetic retinopathy (DR), and to assess the correlation between responses of mfERG and the threshold of the visual field test (VF).

The records of patients with DR (16 eyes, 16 patients) and control subjects (14 eyes, 14 subjects) were retrospectively reviewed. mfERG and VF were divided into Ring 1, Ring 2 and Ring 3 at 6-degree intervals from the central macula. The correlation between the amplitude/peak time and the threshold of each ring was analyzed.

In patients with DR, the amplitude was decreased in all areas, the peak time was delayed in Ring 2 and the threshold was decreased in Rings 2 and 3, compared to control subjects. The amplitude of mfERG and the threshold of VF showed statistically significant positive correlations in Rings 2 and 3 ( p < 0.05). The peak time of mfERG and the threshold of VF showed statistically significant negative correlations in Ring 3 ( p < 0.05).

The threshold of VF was more significantly correlated with the amplitude than with the peak time of mfERG in patients with DR. mfERG and VF were useful tests to assess the macular function, and alteration of macular function was early detected because two tests were conducted at the same time.