Intravitreal Injection of Ranibizumab Versus Sham Before Vitrectomy in Patients With Proliferative Diabetic Retinopathy

Study Overview
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Brief Summary
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Certain percent of the eyes with proliferative diabetic retinopathymay require pars plana vitrectomy (PPV) due to vitreous haemorrhage, proliferative membrane, and tractional retinal detachment. This study will compare intravitreal injection of anti-vascular endothelial growth factor (ranibizumab) versus sham injection before vitrectomy for PDR. The main focus is to see if pre-operative injection of ranibizuman can reduce peri-operative hemorrahge related complications.

Detailed Description
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Eyes responding to panretinal photocoagulation can remain stable for decades, but incomplete responses and relapses can occur in a certain percent of diabetic patients showing as proliferative diabetic retinopathy. At present vitrectomy is the main intervention for those eyes with vitreous hemorrhage, proliferative membrane, and tractional retinal detachment. And the surgical procedure might be complicated because of intraoperative bleeding. And post-operative complications might be also involved. Perioperative use of intraocular anti-VEGF might be associated with less hemorrhage related complications and better visula acuity. This study will compare intravitreal injection of anti-vascular endothelial growth factor (ranibizumab) versus sham injection one week before surgery. The investigators tried to make sure whether pre-operative injection of ranibizuman can reduce reduce intra-operative bleeding, reduce the frequency of using endodiathermy, decrease surgical time, improve microcurculation of retina, and elevte best-corrected visual acuity.

Official Title
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Comparison of Intravitreal Injection of Ranibizumab Versus Sham Injection Before Vitrectomy in Patients With Proliferative Diabetic Retinopathy: a Single-center, Prospective Double-blinded Randomized Controlled Trial

Conditions
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Proliferative Diabetic Retinopathy

Intervention / Treatment
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* Drug: ranibizumab
* Drug: sham
* Procedure: pars plana vitrectomy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: type I or type II diabetes there is clear indications for vitrectomy due to proliferative membrane in the vitreoretinal interface, mild hemorrhage, or tractional retinal detachment retinal large vessels could be detected within one PD away from the edge of optic disc by OCT microcurculation could be detected by FFA in at least one quadrant the patient could tolerant FFA examination Exclusion Criteria: a history of vitrectomy or scleral bucke in the included eye retinal laser photocoagulation treatment within 90 days in the included eye anti-VEGF treatment with 90 days in either eye there is cocurrent neovascular glaucoma in the included eye any reason that might hinde the procedure of vitrectomy, FFA OCT or the observation of ocular fudus a history of cere-brovascular accident or heart stroke renal failure could not attend follow up regularly

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: ranibizumab<br>Intravitreal Injection of 0.5 mg ranibizumabone week before vitrectomy. | Drug: ranibizumab<br>* intravitreal injection of 0.5 mg ranibizumab before vitrectomy<br>* Other names: Lucentis;Procedure: pars plana vitrectomy<br>* surgical procedure to remove the intravitreal hemorrhage and fibrosis membrane, and re-attach the retina, and perform endo laser photocoagulation on retina.<br>* Other names: vitrectomy;|
| Sham Comparator: control<br>Sham intravitreal injection one week before vitrectomy. | Drug: sham<br>* sham intravitreal injection before vitrectomy<br>* Other names: control;Procedure: pars plana vitrectomy<br>* surgical procedure to remove the intravitreal hemorrhage and fibrosis membrane, and re-attach the retina, and perform endo laser photocoagulation on retina.<br>* Other names: vitrectomy;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| perioperative hemorrhage of the surgical eye |  | 3 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| size of retinal non-perfusion area assessed by fluorescene angiography |  | 3 month | 
| macular retinal thickness assessed with optical coherance tomography |  | 3 month | 
| retinal vessel oxygen saturation measured with a retinal oximeter |  | 3 months | 
| best-corrected visual acuity |  | 3 months |