方法：对33例44眼行玻璃体切割术的PDR患者及30例44眼正常对照组志愿者采用光学相干断层扫描(optical coherence tomography， OCT)及多焦视网膜电图(multifocal electroretinogram，mf-ERG)进行检查，观察PDR患者术前与术后及正常对照组黄斑区视网膜厚度的改变及P1波、N1波5环和4象限的振幅密度及潜伏期的变化。

结果：术后随访2mo，正常对照组、PDR组术前及术后两两比较：P1波振幅密度正常组及PDR组术前、术后两两比较，5环及4象限差异均有统计学意义(P<0.05)； P1波潜伏期第1环正常对照组与PDR组术前比较，第3环、第4环、第5环、第2象限、第3象限正常对照组与PDR组术后比较，差异无统计学意义(P>0.05)，其余均有统计学意义(P<0.05)； N1波振幅第1环正常对照组与PDR组术后比较，无统计学意义(P>0.05)，其余均有统计学意义(P<0.05)； N1波潜伏期第3环PDR组术前及术后比较，第1环、第2环、第4象限正常对照组与PDR组术前比较，第5环、第2象限、第3象限正常对照组与PDR组术后比较，差异无统计学意义(P>0.05)，其余均有统计学意义(P<0.05)； 黄斑中心凹视网膜厚度两两比较，差异均有统计学意义(P<0.05)。黄斑中心凹视网膜厚度与P1波、N1波振幅密度及潜伏期的相关性分析显示，除N1波潜伏期在第3象限存在相关性外，其余均无相关性(P>0.05)。

结论：通过应用OCT和mf-ERG对PDR患者玻璃体切割手术前后黄斑区结构与功能的评估，说明玻璃体切割术可有效减轻视网膜黄斑水肿并改善视网膜的感光及传导功能。

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.