AIM:To observe the change of retinal structure and function in macular for patients of proliferative diabetic retinopathy(PDR)before and after vitrectomy.

METHODS:Totally 33 patients 44 eyes of PDR with vitrectomy and 30 cases(44 eyes)of normal control group were inspected with optical coherence tomography(OCT)and multifocal electroretinogram(mf-ERG), the change of retinal thickness in macular and amplitude densities and latencies of P1 wave and N1 wave(5 rings and 4 quadrants)for patients before and after vitrectomy and normal control group were observed.

RESULTS:Patients were followed up for 2 months, normal control group and patients with proliferative diabetic retinopathy before and after vitrectomy pairwise comparison: normal control group and patients group before and after vitrectomy about amplitude densities of P1 wave(5 rings and 4 quadrants)were pairwise compared, the differences were statistically significant(P<0.05); for the latencies of P1 wave, the normal control group compared with the preoperative patients about the 1^st ring, the normal control group compared with postoperative patients about the 3^rd, the 4^th, the 5^th ring and the 2^nd, the 3^rd quadrant, the differences were not statistically significant(P>0.05), the rest were statistically significant(P<0.05); the amplitude of N1 wave about the 1^st ring in normal control group compared with postoperative patients, the differences were not statistically significant(P>0.05), the rest were statistically significant(P<0.05); the latencies of N1 wave about the 3^rd ring in preoperative patients compared with postoperative patients, the normal control group compared with the preoperative patients about the 1^st, the 2^nd ring and the 4^th quadrant, the normal control group compared with postoperative patients about the 5^th ring and the 2^nd, 3^rd quadrant, the differences were not statistically significant(P>0.05), the rest were statistically significant(P<0.05); normal control group and patients with proliferative diabetic retinopathy before and after vitrectomy were pairwise compared in macular about retinal thickness, the differences were statistically significant(P<0.05). The correlation analysis of retinal thickness in macular fovea and the amplitude densities and latencies of P1 wave and N1 wave showed that the rest had no correlation(P > 0.05)except the latencies of N1 wave in the 3^rd quadrant.

CONCLUSION:Measured retinal thickness in macular for the patients with PDR before and after vitrectomy using OCT and mf-ERG, which found that the postoperative retinal thickness was obviously lower than preoperative retinal thickness, showed that vitrectomy reduced macular edema and improve photo sensitive and conductive function of the retina effectively.