AIM: To observe the results of intravitreal injection ranibizumab after pars plana vitrectomy in severe proliferative diabetic retinopathy.

METHODS: In this retrospective non-comparative interventional case series, twelve patients had undergone pars plana vitrectomy with silicone oil tamponade, perfluoropropane tamponade or balanced salt solution tamponade. At the end of the surgery, ranibizumab was injected into vitreous cavity.

RESULTS: Average follows up was 2.75mo. Twelve eyes include vitreous haemorrhage(1/12), vitreous haemorrhage with fibrovascular proliferation(1/12), tractional retinal detachment with vitreous haemorrhage(3/12), tractional retinal detachment with fibrovascular proliferation(2/12), tractional retinal detachment with vitreous haemorrhage and neovascular glaucoma(1/12), tractional retinal detachment with vitreous haemorrhage and fibrovascular proliferation(2/12), tractional retinal detachment with vitreous haemorrhage and fibrovascular proliferation and neovascular glaucoma(1/12), traction-rhegmatogenous retinal detachment with vitreous haemorrhage(1/12). Among these 12 eyes, 8/12 had silicone oil tamponade, 2/12 had perfluoropropane tamponade, and 2/12 had balanced salt solution tamponade. All the patients did not have any therapy before. The retinal attachment rate was 10/10. One patient(1/12)had hyphema after surgery. Postoperative best-corrected visual acuity improved in 9 eyes(9/12), was unchanged in one(2/12), decreased in(1/12)eyes. Eight eyes(8/12)did not have diabetic macular edema after surgery from the optical coherence tomography examination.

CONCLUSION: Intravitreal ranibizumab after pars plana vitrectomy is useful in severe proliferative diabetic retinopathy. It can improve the success rate of surgery; improve postoperative best-corrected visual acuity; minimize the frequence of diabetic macular edema; minimize the frequence of operations and postoperative complications.