AIM:To observe the changes of photopic negative response(PhNR)of multifocal electroretinogram(mf-ERG)in patients with diabetic macular edema(DME)before and after treatment with Aflibercept.

METHODS: A total of 37 patients(37 eyes)with DME who visited the Aier Eye Hospital of Wuhan University(Wuhan Aier Eye Hospital)from May 2019 to June 2022, and 0.05 mL of aflibercept was injected per month for consecutive 3mo were included in this retrospective cohort study. Another 20 cases(20 eyes)with normal physical examination to exclude related eye diseases were selected as the control group. The PhNR amplitude of mf-ERG, best-corrected visual acuity(BCVA; LogMAR), central retinal thickness(CRT), capillary plexus in macular area and vessel density(CPVD)of the participants between the two groups were compared before and after treatment.

RESULTS: The PhNR amplitude of mf-ERG in DME patients before treatment(201.69±80.92nV)was significantly lower than that in the normal control group(398.87±77.92nV; P<0.01), and the average PhNR amplitude of mf-ERG in DME patients at 6mo after treatment was significantly higher than that before treatment(P=0.036), but it was still significantly lower than the normal control group at 6mo after treatment(P=0.031). In addition, the BCVA(LogMAR)of DME patients increased from 0.64±1.33 to 0.37±1.39(P=0.021)at 6mo after treatment, and CPVD significantly increased compared to that before treatment(P=0.029). Meanwhile, the PhNR amplitude of mf-ERG in DME patients at 6mo after treatment was positively correlated with CPVD at 6mo after treatment(r=0.448, P=0.043), and negatively correlated with BCVA(LogMAR)and CRT(r=-0.647, P=0.011; r=-0.337, P=0.032).

CONCLUSION: The PhNR amplitude of mf-ERG in DME patients increased significantly after receiving aflibercept, and it can be used to observe and evaluate the functional changes of retinal ganglion cells in DME patients.