Preoperative Injection of Bevacizumab Prior to Vitreoretinal Surgery in Diabetic Tractional Retinal Detachment

Study Overview
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Brief Summary
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Vitreoretinal surgery for epiretinal proliferation tractional retinal detachment associated with proliferative diabetic retinopathy (PDR) is often complicated by hemorrhage from fibrovascular tissue. To control the bleeding during tissue dissection multiple measures and techniques are used. Bevacizumab is an anti VEGF antibody which has been used to induce regression of ocular neovascularization. Its intraocular injection has been increasingly used for treatment of choroidal neovascularization (CNV) associated with age related macular degeneration (AMD) with fairly good success.Also it has been shown to be effective for treatment of PDR complicated with vitreous hemorrhage and iris neovascularization. We hypothesized that if anti-angiogenic agents, such as bevacizumab are injected into the vitreous cavity before vitrectomy in cases of PDR; there may be partial regression of neovascularization resulting in less intraoperative (and postoperative) hemorrhage. This can make the operation easier and shorter and lessen the need for intraocular cautery.. In this study diabetic patients who are candidated for vitrectomy with similar complexity scores will be randomized to preoperative injection or no injection of 2.5 mg Bevacizumab .In the injection group, 2.5 mg of bevacizumab (0.1 ml of commercially available Avastin vial, Genentech, inc. South San Francisco, CA) will be injected into the vitreous 3-5 days before operation. During each operation, the number of endodiathermy applications, backflush needle applications and the duration of surgery will be recorded by an independent observer. Also, type of tamponade, post operation vitreous hemorrhage and 3 months postoperative visual acuities wil be recorded. all these parameters will be compared in two groups.

Detailed Description
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Eligibility criteria: Diabetic tractional retinal detachment-complexity score between 4 and 8 Main outcome measures: best corrected visual acuity-anatomic condition of the retine(re-attachment of the retina)

Official Title
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Preoperative Injection of Bevacizumab Prior to Vitreoretinal Surgery in Diabetic Tractional Retinal Detachment

Conditions
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Intravitreal Bevacizumab Injection, Pars Plana Vitrectomy, Tractional Retinal Detachment, Diabetic Retinopathy

Intervention / Treatment
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* Drug: Bevacizumab


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Those patients with tractional retinal detachment who are candidated for pars plana vitrectomy. Complexity score between 4 and 8. Exclusion Criteria: Previous vitreoretinal surgery. Presence of any other vitreoretinal pathology such as past or present uveitis, and retinal artery or vein occlusion.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intervention group<br>Intravitreal Bevacizumab will be injected 2.5 mg IVB 3-5 days before operation in diabetic patients who were candidates for vitrectomy before performing pars plana vitrectomy | Drug: Bevacizumab<br>* one intravitreal injection of 2.5 mg Bevacizumab 3-5 days before performing pars plana vitrectomy<br>* Other names: Brand name of Bevacizumab is Avastin;|
| No Intervention: Control group<br>no injection before performing pars plana vitrectomy in diabetic patients who were candidates for vitrectomy | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Best Corrected Visual Acuity | Post operative best corrected visual acuity ( best distance vision with eyeglasses or contact lenses) | last follow up, an average of 7 months post-operation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Anatomic Status of the Retina | Number of Participants with Postoperative Vitreous Hemorrhage | Last follow up, an average of 7 months post-operation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Intravitreal Bevacizumab injection, Pars plana vitrectomy, tractional retinal detachment, Diabetic retinopathy