BCD patients with homozygous IVS6-8del17bp/insGC or compound heterozygous IVS6-8del17bp/insGC and IVS8-2A>G mutations appeared to have more severe disease phenotype based on electrophysiological testing. The level of visual loss in BCD is related to the severity of retinal thinning.

Abstract. Multifocal electroretinography (mfERG) is an investigation that can simultaneously measure multiple electroretinographic responses at different retinal locations by cross-correlation techniques. mfERG therefore allows topographic mapping of retinal function in the central 40--50 of the retina. The strength of mfERG lies in its ability to provide objective assessment of the central retinal function at different retinal areas within a short duration of time. Since the introduction of mfERG in 1992, mfERG has been applied in a large variety of clinical settings. This article reviews the clinical applications of mfERG based on the currently available evidence. mfERG has been found to be useful in the assessment of localized retinal dysfunction caused by various acquired or hereditary retinal disorders. The use of mfERG also enabled clinicians to objectively monitor the treatment outcomes as the changes in visual functions might not be reflected by subjective methods of assessment. By changing the stimulus, recording, and analysis parameters, investigation of specific retinal electrophysiological components can be performed topographically. Further developments and consolidations of these parameters will likely broaden the use of mfERG in the clinical setting.

In patients on hydroxychloroquine, mfERG response amplitude correlated with both the 10-2 visual field MD values and with the cumulative dose of hydroxychloroquine used. The use of mfERG can provide objective measurement of retinal function in patients on hydroxychloroquine and may provide supplementary quantitative information to visual field findings.

To evaluate the correlation between functional and anatomical assessments with multifocal electroretinography (mfERG) and optical coherence tomography (OCT) in patients with acute central serous chorioretinopathy (CSC). Thirty-four eyes of 34 patients with acute CSC underwent mfERG and OCT examinations. First-order mfERG N1 and P1 response amplitudes and latencies were analyzed.OCT parameters measured included central subretinal fluid (SRF) thickness, central retinal thickness, total central foveal thickness, vertical, and horizontal diameters of SRF, and macular volume. Correlation analyses were performed between best-corrected visual acuity (BCVA), mfERG parameters, and OCT measurements. Correlation analysis showed that logMAR BCVA was significantly correlated with mfERG N1 amplitudes of rings 1 and 2 (P = 0.006), N1 latency of ring 4 (P = 0.012), and P1 latency of ring 1 (P = 0.036). No significant correlation was observed between logMAR BCVA and any of the OCT measurements. For the correlation between mfERG parameters and OCT measurements, mfERG N1 and P1 latencies of the paracentral rings were significantly correlated with the central SRF thickness (P < or = 0.024), diameters of the SRF (P < or = 0.018), and macular volume (P < or = 0.030). MfERG responses but not OCT measurements correlated with logMAR BCVA in patients with acute CSC. The amount of SRF nonetheless correlated with the mfERG N1 and P1 latencies of the paracentral rings, suggesting that impairment in the conduction of electrical responses in the paracentral macula is proportional to the severity of serous macular detachment in CSC. MfERG and OCT can complement each other in the functional and anatomical assessments in CSC.