Severe Proliferative Diabetic Retinopathy Treated By Pars Plana Vitrectomy Assisted By Medicine Intravitreal Injection

Purpose:To observe efficacy of severe proliferative diabetic retinopathy treated by pars plana vitrectomy, PPV assisted by intravitreal medicine injection. The complications and the maneuver difficulty of this surgery were analyzed.Methods:60cases (65eyes) who diagnosed as proliferative diabetic retinopathy without laser treatment were included. They were divided into A and B group. Group A was treated with PPV assisted with intravitreal medicine injection.1.25mg bevacizemab was injected into the vitreous cavity 5-7 days pre-operatively. After PPV, lmg triamcinolone acetonide was intravitreal injected. Group B was treated with PPV only. Viscual acuity of 1 week,1 month and 3 months post-operative were tested with Snellen Chart. Intraocular pressure was tested with automatic tonometer. Macular edema was detected with Optical Coherence Tomography. Fundus was observed with B scan or slit-lamp plus+100D lens. The complications, maneuver difficulty (surgery time and silicone oil injection rate), visual acuity post-operative and retinal reattachment rate were compared.Results:1. Complications during surgery Hemorrhage rate of group A was 29%. New hole formation rate was 23%. Residual membrane rate was 8%. Hemorrhage rate of group B was 81%. New hole formation rat was 87%. Residual membrane rate was 49%. The complication of group A was less than group B during surgery. The difference was statistical significant (p<0.01)2. Complications post-operativeMembranous exudates rate of group A was 8.8%. Recurrent vitreal cavity hemorrhage rate was 5.9%. Retinal neovascular membrane proliferation rate was 0.. Membranous exudates rate of group B was 64.5%. Recurrent vitreal cavity hemorrhage rate was 19.4%. Retinal neovascular membrane prliferation rate was 9.7%. Membranous exudates rate, recurrent vitreal cavity hemorrhage rate and retinal neovascular membrane proliferation rate of group A were less than group B (p<0.05)3. Surgery timeSurgery time of group A was 110minutes whereas group B was 140minutes. Group A was 30minutes less.4. Silicone oil filling rateSilicone oil filling rate of group A was 30% whereas group B was 60%(P<0.01).5. Visual acuity post-operativeThe best corrected visual acuity of two groups 1 and 3 months post-operative was similar (P>0.05)6. Retinal reattachment ratesThere was no difference in retinal reattachment rate in two groups. They were 100% and 98%.Conclusions:In two groups, there was no difference in visual acuity post-operative and retinal reattachment rate. For severe proliferative diabetic retinopathy, pars plana vitrectomy assisted by medicine intravitreal injection could short surgery time and decrease maneuver difficulty. The complications during surgery and post-operative were less at the same time.