Abstract
The pattern electroretinogram (PERG) is a sensitive test for investigation of the proximal retina. For monocular recording, the contralateral corneal reference (CCR) electrode position has been suggested as a possible alternative to the conventional ipsilateral temporal reference (ITR). We therefore compared the effect of these electrode positions on 26 subjects (median age 45.5years, IQR 24.5–61.5). The signals were recorded monocularly with DTL nylon fibre electrodes. The visual stimuli were high contrast 19′ black–white checkerboard patterns, reversing 4 times/s. PERG responses obtained from the CCR gave larger amplitudes and the increase in amplitude was statistically significant (P<0.001). Because the CCR signal is larger, new normative ranges must be established to avoid false negative results.