Objective:To explore the MULTIFOCAL ELECTRORETINOGRAM in patients with nonproliferative diabetic retinopathy with clinically-significant macular edema. Methods: Forty-one eyes with clinically significant macular edema were tested. The latencies and amplitudes of average responses of 5 eccentric rings from 0 to 26 degrees relative to the fixation point were compared with normal values obtained from 13 nondiabetic subjects. Results: Local ELECTRORETINOGRAM responses were significantly delayed and decreased in amplitude in patients with clinically-significant macular edema.  Conclusion: MULTIFOCAL ELECTRORETINOGRAM can be used to quantify the visual function in clinically significant macular edema.  

Data suggest that the MULTIFOCAL electroretinography (mfERG) may have a role in the assessment of patients with central retinal vein occlusion (CRVO). To explore the mfERG responses in patients with CRVO. mfERG responses were recorded at 61 discrete retinal locations from both eyes of 25 patients diagnosed with retinal vein occlusions within 3 weeks of onset. The latencies and amplitudes of average responses of 5 eccentric rings from 0 to 26 degrees relative to fixation, and grouped central and peripheral rings of involved eyes were compared with values obtained from 13 normal fellow eyes of these subjects. The mfERG responses obtained from eyes with CRVO were significantly different from those derived from the fellow eye, especially when the rings are grouped as central and peripheral. mfERG is a new, safe, non-invasive, and quick investigative tool to assess retinal function. Our results suggest that mfERG could be a useful electrophysiologic test in clinical evaluation and determination of the severity of underlying ischemia in patients with retinal vein occlusion. Further studies are needed to evaluate its role as a prognostic method to determine which eyes are prone to serious complications. This is the first report of mfERG results in Iran.

Purpose: To evaluate ELECTRORETINOGRAM (ERG) changes after silicone oil removal.Methods: Scotopic and photopic ERGs, and best-corrected visual acuity (BCVA) were checked before and shortly after silicone oil removal in eyes that had previously undergone vitrectomy and silicone oil injection for complex retinal detachment. Preand postoperative ERG a- and b-wave amplitudes were compared.Results: Twenty-eight eyes of 28 patients including 20 male and 8 female subjects with mean age of 39.3 ± 0.06 (range, 12 to 85) years were studied. Mean interval from primary vitreoretinal surgery to silicone oil removal was 21.04 ± 0.52 (range, 7 to 39) months. Mean duration from silicone oil removal to second ERG was 13.04 ± 1.75 (range, 10 to 16) days. Before silicone oil removal, mean a-wave amplitudes in maximal combined response, rod response and cone response ERGs were 27.4 ± 19.9, 7.2 ± 4.5 and 5.5 ± 3.4 mv, respectively. These values increased to 48.8 ± 31.9, 15.1 ± 14.4 and 17.4 ± 22.2 mv, respectively after silicone oil removal (P<0.001). Mean b-wave amplitudes in the same order, were 69.41 ± 51, 41.2 ± 30.4 and 25.1 ± 33.9 mv before silicone oil removal, increasing to 165.6 ± 102.5, 81.7 ± 53.7 and 44.7 ± 34.1 mv respectively, after silicone oil removal (P<0.001). Mean BCVA significantly improved from 1.10 ± 0.34 at baseline to 1.02 ± 0.33 logMAR after silicone oil removal (P<0.001).Conclusion: The amplitudes of ERG a- and b-waves under scotopic and photopic conditions increased significantly shortly after silicone oil removal. An increase in BCVA was also observed. These changes may be explained by the insulating effect of silicone oil on the retina.