Pre- and Intra-operative Intravitreal Bevacizumab Injection in Diabetic Vitrectomy

Study Overview
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Brief Summary
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The purpose of this study is to determine the effect of pre- and intra-operative bevacizumab injection on postoperative vitreous hemorrhage after diabetic vitrectomy.

Detailed Description
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Postoperative vitreous hemorrhage(VH) is a common complication after vitrectomy for proliferative diabetic retinopathy. Persistent or recurrent VH can delay visual rehabilitation and give patients much trouble. There have been efforts to lower the incidence of postoperative VH such as using intraoperative gas tamponade and preoperative bevacizumab injection. Bevacizumab(Avastin) is a potent inhibitor of angiogenesis and has been shown to decrease retinal and iris neovascularization in proliferative diabetic retinopathy. Recently there have been reports showing that preoperative intravitreal bevacizumab (IVB) injection could reduce intraoperative bleeding from abnormal vessels and could make surgery easier and more successful.Our hypothesis is that preoperative bevacizumab injection could reduce postoperative VH by way of decreasing the amount of abnormal vessels and intraoperative injection could also reduce postoperative VH by inhibiting the vessel formation after surgery. To prove our hypothesis, we started the prospective randomized comparative study to determine the effect of pre- and intra-operative IVB injection on postoperative vitreous hemorrhage after diabetic vitrectomy.

Official Title
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Efficacy Study of Pre- and Intra-operative Intravitreal Bevacizumab Injection on Postoperative Vitreous Hemorrhage After Diabetic Vitrectomy

Conditions
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Proliferative Diabetic Retinopathy, Vitreous Hemorrhage

Intervention / Treatment
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* Drug: Bevacizumab


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing first vitrectomy for complications of proliferative diabetic retinopathy such as vitreous hemorrhage, tractional fibrovascular membrane proliferation, tractional or combined retinal detachment) Exclusion Criteria: Follow-up period of less than 6 months Intraoperative use of long-acting gas or silicone oil Repeat vitrectomy after first vitrectomy for diseases other than vitreous hemorrhage Not first vitrectomy Uncontrolled hypertension Medical history of abnormal blood coagulation Time interval between IVB injection and PPV longer than 2 weeks and recent history (within 3 months) of IVB treatment

Ages Eligible for Study
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Minimum Age: 20 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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Preop IVB<br>Patients will receive intravitreal injection of 1.25 mg of bevacizumab (0.05 ml) 1 to 14 days before vitrectomy | Drug: Bevacizumab<br>* Patients will receive intravitreal injection of 1.25 mg of bevacizumab (0.05 ml)<br>* Other names: avastin;|
| Experimental: Intraop IVB<br>Patients will receive intravitreal injection of 1.25 mg of bevacizumab (0.05 ml) at the end of vitrectomy | Drug: Bevacizumab<br>* Patients will receive intravitreal injection of 1.25 mg of bevacizumab (0.05 ml)<br>* Other names: avastin;|
| No Intervention: No IVB<br>Patients will not receive bevacizumab before nor during vitrectomy | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Recurrent VH Incidence (Early and Late) | Recurrent VH was defined as a new episode of grade 1 or more VH occurring more than 1 week after surgery. Early recurrent VH was VH occurring <= 4 weeks and late recurrent VH was VH occurring >4 weeks after surgery. | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Initial Time of Vitreous Clearing (ITVC) | The interval in number of days for VH of grade 1 or more observed at postoperative day 1 to clear-up completely. VH of grade 1 was defined as mild vitreous hemorrhage with visible fundus details, but difficult to evaluate the retinal nerve fiber layer or small vessels. | 6 months | 
| Visual Outcome | Best-corrected visual acuity (BCVA) at postoperative 6 months | 6 months | 
| Postoperative Resolution of Neovascularization |  | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Proliferative diabetic retinopathy, vitrectomy, bevacizumab, vitreous hemorrhage