Long-term Follow-up After Vitreous Surgery For Proliferative Diabetic Retinopathy

Now over 130 million individuals are afflicted with diabetes worldwild.Diabetic retinopathy is the most common microvascular complication of diabetes,resulting in blindness for over 10,000 people with diabetes per year.Therefore,diabetic retinopathy remains one of the chief causes of visual loss in the people domestic and overseas in 21 century.Althought there are many new interventions for DR,such as antivascular endothelial growth factor agents,intravitreal steroid,protein kinase C inhibitors angiotensin converting enzyme inhibitors and the control of hyperglycemia,hypertension and serum lipid,however,to the patients with vitreous hemorrhage and severe proliferative diabetic retinopathy,vitreous surgery is the most effective and direct method now.Objectives1.To evaluate effecting of vitrectomy for the treatment of proliferative diabetic retinopathy eyes,different groups of eyes had undergone vitreous surgery were made according to duration of diabetes,with or without hypertension and different PDR stages and compared improvement of visual function postoperative to preo- perative respectively.2.According to whether preoperative PRP,phacoemulsification with intraocular lens implantation,removal of the internal limiting membrane,use of various vitreous substitutes and intravitreal TA were performed during the vitreous surgery or not, different groups were made and compared their visual function postoperative to preoperative respectively in order to evaluate benefis of these methods for the treatment of PDR.Methods1.120 consecutive patients(146 eyes)who underwent vitrectomy for prolife- rative diabetic retinopathy during January 2005 to January 2007 were retrospec- tively analysed.All cases were followed up for 12～36 months.2.Compared PDR eyes' postoperative visual function to preoperative respectively according to different methods combined with vitrectomy. Results1.Patients' visual acuity got improved significantly at postoperatively 1 week and at last follow-up(P=0.000＜0.05),and 76.7%patients improved their visual acuity with different degrees.2.The stage of PDR affects prognosis of vitreous surgery obviously(P=0.013＜0.05),and eyes of theⅣPDR group tend to have better visual acuity significantly than the eyes ofⅤandⅥPDR groups respectively(P=0.000,0.000＜0.05).3.Eyes of the balanced salt solution group improved their visual acuity significantly compare to the silicon-oil tamponade and inert-gas tamponade eyes respectively (P=0.000,0.000＜0.05).PDRⅣ,PDRⅤand PDRⅥeyes accounted 82%,39% and 5%in the balanced salt solution group respectively;PDRⅣ,PDRⅤand PDRⅥeyes accounted 6%,25%and 39%in the inert-gas group respectively; PDRⅤand PDRⅥeyes accounted 37%and 56%in the clilicon-oil group respectively.4.There is a significant difference in IOP postoperatively compared to preoperatively (P=0.000＜0.05).Among each follow-up,lOP at one day after surgery increased significantly(P=0.006＜0.05),but IOP at one week after surgery and last follow-up appears no significant difference compared to preoperative period (P=0.468,0.064).And There is also a significant difference in IOP elevation after surgery acorrding to different vitreous substitutes(P=0.001＜0.05).IOP elevation in inert-gas tamponade group appears significant difference to silicon-oil tamponade and balanced salt solution groups(P=0.020,0.000).IOP increased in inertgas tamponade group at early postoperation and can be stable at normal IOP levels within one week.5.Duration of diabetes,with or without hypertension affected prognosis of vitrectomy with no significant difference(P＞0.05).Whether phacoemulsification with intraocular lens implantation,removal of the internal limiting membrane and intravitreal TA were performed affected prognosis of vitrectomy with no significant difference(P＞0.05),but visual acuity postoperative tends to be improved.Conclusion 1.Patients' visual recovery can be well improved by vitreous surgery,which indicated that vitreous surgery was an safe and effective precedure for treating proliferative diabetic retinopathy.2.Eyes of the PDRⅣgroup improved their visual acuity significantly by surgery compared to the PDRⅤand PDRⅥeyes respectively;in addition,improvement of visual acuity for balanced salt solution group eyes is more significant than other tamponade groups.Therefore,vitrectomy should be performed as soon as possible for patients with proliferative diabetic retinopathy to achieve best prognosis.3.Acorrding to the different degrees of severity in PDR eyes,we can't get the conclusion that the balanced salt solution endotamponade eyes have better visual acuity outcomes significantly only due to different vitreous substitutes now.4.Phacoemulsification with intraocular lens implantation,removal of the internal limiting membrane and intravitreal TA are effective methods for treating proliferative diabetic retinopathy.5.More larger,multicentre,random and controlled trials are needed to explore roles of different factors in improving visual function after vitrectomy.