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.  

Purpose: To assess the MULTIFOCAL electroretinography ((MFERG)) responses in patients with branch retinal vein occlusion (BRVO). Methods: (MFERG) responses were recorded at 61 discrete retinal locations from 13 eyes of 12 patients diagnosed with superior temporal branch retinal vein occlusion within 3 weeks of onset. The latencies and amplitudes of average responses at 5 regions including the center and 4 quadrants; and temporal, nasal, superior and inferior hemispheres were compared with values obtained from 17 normal fellow eyes of patients with BRVO. Results: The (MFERG) responses obtained from eyes with BRVO were significantly different from those derived from the fellow eyes, especially when the hemispheres were compared. Conclusion: As a new non-invasive investigative tool for assessing retinal function, (MFERG) could be a useful electrophysiologic test in clinical evaluation and determination of the severity of underlying ischemia in patients with branch retinal vein occlusion. Further studies are needed to evaluate its role as a prognostic tool to determine eyes prone to serious complications.    

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 the effect of intraviteral bevacizumab (IVB) in diabetic macular edema (DME), using MULTIFOCAL electroretinography ((MFERG)).Methods: Sixty-four eyes of 32 patients with bilateral symmetric clinically significant macular edema (CSME) were included in the study. After taking a baseline (MFERG), macular photocoagulation (MPC) was done in all eyes. After 7 days, 1.25 mg of bevacizumab was randomly injected in one eye of each patient and the other eye assigned for sham injection. (MFERG) was repeated 8 weeks after injection, and changes in visual acuity and (MFERG) compared in two groups. Results: The mean best corrected visual acuities (BCVAs) at baseline were 0.55 in IVB group and 0.51 in control group and at 8th week were 0.41 and 0.53 respectively, also the amplitude and implicit time showed significant improvement in (MFERG). Significant improvement in visual acuity and amplitude of waves of (MFERG) were observed compared with sham group. Conclusion: IVB injection can augment the effect of MPC in DME and can be used as an adjunctive treatment in these cases.

Purpose: To analyze microvascular changes in patients with retinitis pigmentosa (RP) with relatively preserved visual acuity (VA), using swept source optical coherence tomography (SS‑ OCT) angiography to correlate results to macular function and structure. Methods: This was a case– control study conducted over 70 eyes of 35 RP patients with relatively preserved VA. All patients underwent a complete ophthalmic examination, including SS-OCT, OCT angiography (OCT‑ A), fundus autofluorescence (FAF), and MULTIFOCAL ELECTRORETINOGRAM ((MFERG)). Thirty‑ four eyes of 34 healthy controls of age‑ , sex‑ , and axial length‑ matched (control group), were also analyzed. The main outcome measures were foveal and parafoveal vascular densities (FVDs and PFVDs) in the superficial capillary plexus (SCP) and deep capillary plexus (DCP), foveal avascular zone (FAZ) and its enlargement coefficient and their correlation with macular function (by means of VA and (MFERG)), and structure (by means of FAF and SS‑ OCT). Results: In the RP group, PFVD was 25. 99 ± 5. 2% in the SCP and 34. 47 ± 2. 37% in the DCP and were significantly lower as compared to control group (P < 0. 0001; P = 0. 0026, respectively). Enlargement coefficient of FAZ was 1. 78 ± 0. 79. We found a statistically significant correlation between VA and PFVD in the DCP (P < 0. 0001), FAZ disruption in the SCP (P = 0. 006) and enlargement coefficient of FAZ (P = 0. 01). The parafoveal DCP density was significantly correlated with P1 amplitude (P = 0. 005) in rings 2, 3, 4, and 5 of the (MFERG). We found a statistically significant correlation between parafoveal density in the DCP, thickness of ganglion cell complex (GCC) (P = 0. 001), and the width of ellipsoid band (P = 0. 041). Parafoveal SCP density was also correlated to GCC (P = 0. 033). Conclusions: We showed that vascular alteration in RP begins at the level of the DCP, which affects the outer retina and leads to a narrowing of the ellipsoid. The alteration of the SCP would occur later in the evolution of the disease. Vascular changes occur early during RP and were highly correlated to retinal function and structure. OCT‑ A seems to be a good tool to quantify vascular network loss and could play a central role in staging, prognosis, and monitoring disease progression.

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.

Purpose: To investigate the effect of Ozurdex (dexamethasone intravitreal implant) on MULTIFOCAL electroretinography ((MFERG)) findings during the treatment of macular edema secondary to the central retinal vein occlusion (CRVO). Methods: Fifteen eyes of 15 patients who were treated with Ozurdex implant due to CRVO‑ related macular edema were included in this study. Best corrected visual acuity (BCVA), central macular thickness (CMT), and (MFERG) evaluations were performed for all patients before injection of Ozurdex. After the injection, BCVA and CMT were measured at months 3 and 6 and (MFERG) test was performed at month 6 for all patients. Results: Pre‑ implantation (MFERG) P wave amplitude values of r1, r2, r3, r4 and r5 were 57. 8 ± 14. 8, 25. 1 ± 10. 6, 17. 2 ± 7. 3, 12. 0 ± 5. 0 and 7. 1 ± 3. 6 nV/deg² , respectively. They increased to 72. 9 ± 33. 2, 31. 2 ± 9. 3, 22. 6 ± 7. 6, 15. 6 ± 7. 1 and 10. 9 ± 5. 7 nV/deg² , respectively, at month 6. However, these increases were not statistically significant (all P > 0. 05). Pre‑ implantation (MFERG) r1, r2, r3, r4 and r5 P wave implicit times were 40. 1 ± 10. 9, 39. 4 ± 3, 38. 4 ± 3. 4, 38. 2 ± 3. 1 and 39. 3 ± 2. 2 ms, respectively and these values were measured as 38. 9 ± 8. 2, 38. 4 ± 4. 7, 37 ± 3. 8, 37. 5 ± 4. 6 and 37. 7 ± 4. 7 ms at 6 months. Although there were reductions in P wave implicit times in all rings, they were not statistically significant (all P > 0. 05). Conclusion: In this prospective study, we found that the Ozurdex implant had no effect on (MFERG) findings 6 months after insertion for treatment of CRVO‑ related macular edema.