Pattern ERG in central serous retinopathy.

Background: To evaluate the pattern electroretinogram (PERG) in central serous retinopathy.

Methods: In this prospective study, 20 patients with recent onset (<6 weeks) unilateral CSR were studied with the fellow eye acting as control. BCVA, psychophysical parameters, FFA, OCT, flash and pattern ERG were evaluated.

Results: The mean P50 amplitude in the affected eye at presentation was 2.36 ± 0.8 μv compared to 3.24 ± 0.85 μv in the normal eye. At 12 weeks, the mean P50 amplitude in the affected eye was 3.16 ± 0.88 μv compared to 3.63 ± 0.82 μv in the normal eye. The reduction of 27 % in P50 amplitude even after recovery was statistically significant (P < 0.001). A reduction of 19.77 % in the amplitude of N95 wave in the affected eye compared to the normal eye was seen, which was statistically significant (P < 0.001). In the affected eye, there was statistically significant improvement in the psychophysical tests at 12 weeks.

Conclusions: This study reveals that P50 component of the PERG is reduced in cases of CSR, indicating functional disturbance of the macular photoreceptors. A normal flash ERG indicates that pathology is electrophysiologically localised to macula without affecting general retina. Residual deficit in the PERG explains poor quality of vision in spite of normal anatomical apposition and quantitative 6/6 visual acuity.