Correlation Between Multifocal Electroretinogram and Optical Coherence Tomography Findings With Visual Acuity in Patients With Macular Dystrophy

Purpose: To correlate the optical coherence tomography (OCT) findings and multifocal electroretinogram (mf-ERG) responses with visual acuity (VA) in patients with macular dystrophies. Methods: A cross-sectional study including 62 eyes of 31 patients diagnosed with macular dystrophy was conducted. All participants underwent assessment of corrected-distance VA, mf-ERG responses (data analysis were restricted to ring 1), and OCT parameters, including central macular thickness (CMT) and the integrity of the inner segment/outer segment (IS/OS) junction. The correlations between VA with mf-ERG responses and OCT parameters were analyzed. Results: A statistically significant moderate correlation was found between corrected-distance VA and CMT (r = 0.497, P < .001), the mf-ERG amplitudes of N1 (r = 0.469, P < .001), N2 (r = 0.517, P < .001), and P1 (r = 0.494, P < .001), the mf-ERG latencies of N2 (r = −0.301, P = .017), and the integrity of the IS/OS junction (r = −480, P < .001). There was a statistically significant weak negative correlation between corrected-distance VA of the studied eyes with mf-ERG latencies of N1 (r = −0.269, P = .034) and P2 (r = −0.283, P = .026). Regression analysis showed that CMT and IS/OS junction integrity were the most significant predictors of VA, alongside mf-ERG amplitudes and latencies. Conclusions: CMT and the integrity of the IS/OS junction are strong structural indicators for visual function in patients with macular dystrophies. Moreover, mf-ERG is considered to play a crucial role in identifying early functional impairment before irreversible anatomic changes occur.