The implicit time is thought to be more susceptible than the amplitude to injury of photoreceptors and the outer plexiform layer [19,22,23,28]. SD) after treatment (= 0.03) (Fig. 2A). The mean CMT measured by OCT at baseline was 319.43 128.09 m. At one month post injection, the mean CMT measurement had decreased to 268.29 72.09 m (Fig. 2B). Statistically Crocin II significant difference was found between the CMT at baseline and after treatment (= 0.04). TMV was 11.65 2.45 mm3 before treatment and decreased to 10.52 1.78 mm3 after treatment. There Crocin II was significant improvement in TMV after injection (= 0.01) (Fig. 2C). Open in a separate windows Fig. 2 Changes in best corrected visual acuity (A), central macular thickness (B), and total macular volume (C) before and after intravitreal injection (Wilcoxon’s signed rank test, 0.05). logMAR = logarithm of the minimum angle of resolution. In mfERG, the amplitude of N1 in rings 1 to 3 changed after treatment, but no statistically significant differences were found (ring 1, = 0.18; ring 2, = 0.27; ring 3, = 0.55) (Fig. 3A). The amplitude of P1 in rings 1 to 3 increased after injection with statistical significance (ring 1, = 0.03; ring 2, = 0.04; ring 3, = 0.02) (Fig. 3B). From ring 1 to 3, the implicit time of N1 and P1 decreased after injection compared with baseline, and statistical analysis revealed significant difference (P1: ring 1, Tpo = 0.02; ring 2, = 0.01; ring 3, = 0.03; N1: ring 1, = 0.01; ring 2, = 0.02; ring 3, = 0.01) (Fig. 4). Open in a separate windows Fig. 3 Changes of N1 (A) and P1 (B) amplitude in multifocal electroretinogram before and after intravitreal injection (Wilcoxon’s signed rank test, 0.05). Open in a separate windows Fig. 4 Changes of N1 (A) and P1 (B) implicit time in multifocal electroretinogram before and after Crocin II intravitreal injection (Wilcoxon’s signed rank test, 0.05). There appeared to be a linear relationship between changes of N1 implicit time in ring 1 and the BCVA however, other factors had no significant difference (Table 1). The correlation between CMT and mfERG values was not significant (Table 2). The TMV correlated with the implicit time of N1 and Crocin II P1 in ring 1, P1 in ring 2, and N1 in ring 3, but without statistical significance. A reverse correlation was seen between TMV and amplitude in rings 1 and 2, but not at a significant level (Table 3). Table 1 Correlation with parameters of multifocal electroretinography and best corrected visual acuity (BCVA) Open in a separate windows *Spearman’s Rho, 0.05. Table 2 Correlation between parameters of multifocal electroretinography responses and central macular thickness (CMT) Open in Crocin II a separate windows *Spearman’s Rho, 0.05. Table 3 Correlation between parameters of multifocal electroretinography and total macular volume (TMV) Open in a separate windows *Spearman’s Rho, 0.05. Discussion Bevacizumab is usually a recombinant humanized monoclonal antibody to human VEGF that binds to VEGF and blocks it from binding to its receptors in tumor tissues. Intravitreal bevacizumab injection is usually increasingly used as an off-label therapy in ophthalmology, and shows benefits in the improvement of visual acuity and anatomical changes of many vision diseases [8-14,16]. As we hypothesized, visual acuity and anatomical changes were associated with functional changes of the retina, thus we used mfERG, which assesses retinal function, to confirm functional changes after injection. The use of mfERG enables topographic mapping of retinal function in.