Comparison of 23G and 25G vitrectomy used for proliferative diabetic retinopathy

Objective To compare the clinical outcomes,operative process and complications of 23G and 25G vitrectomy for proliferative diabetic retinopathy (PDR).Methods A prospective randomized controlled study.Ninety eyes of 83 patients with PDR were enrolled and randomly divided into 23G group (47 eyes) and 25G group (43 eyes),and underwent 23G or 25G vitrectomy respectively.The sixth months after operation was selected as the last follow-up visit and the best corrected visual acuity,intraocular pressure and postoperative complications of the two groups were compared.SPSS17.0 was used for statistic analysis.Results The surgery time was longer and the expenditure was higher in 25G group,but more patients needed sutures in 23G group.In 23G group,the number of eyes with BCVA≥0.02 at postoperative 1 month,3 and 6 months were 31.9％(15/ 47),55.3％(26/47) and 61.7％(29/47),respectively,and only the difference between 3 months and 1 month was significant (x2=5.23,P ＜0.05).In 25G group,the number of eyes with BCVA≥0.02 at postoperative 1 month,3 and 6 months were 27.9％(12/43),53.5％(23/43) and 58.1％(25/43),respectively,and only the difference between 3 months and 1 month was significant (x2=5.83,P ＜0.05).The intraocular pressure was significantly higher in 23G group than 25 G group on the first day post operation (F =7.65,P ＜0.05),but they all became normal within 1 week.There was no significant difference in iatrogenic tear and postoperative inflammatory reaction between the two groups (x2=0.71,0.54; P ＞0.05).Conclusions In treatment of complicated diseases such as PDR,25G vitrectomy is also an effective and safe method compared with 23G,both of them can achieve ideal therapeutic effect. Key words: Micro incision vitrectomy;  Proliferative diabetic retinopathy;  Prospective controlled study