Intravitreal Avastin Versus Intravitreal Avastin and Triamcinolone in Central Retinal Vein Occlusion(CRVO)

Study Overview
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Brief Summary
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In this study we intend to evaluate and compare the outcomes of intravitreal avastin versus avastin and triamcinolone on improving the visual acuity and macular edema and late complications of CRVO like NVI and NVG.

Detailed Description
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Central retinal vein occlusion (CRVO) is a common retinal vascular disorder with potentially complications like reduced vision resulting from extensive intraretinal hemorrhage, retinal ischemia and persistent macular edema and neovascular glaucoma secondary to iris neovascularization. Macular edema is a common cause of severe visual loss in both branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO). Natural history data indicate that CRVO patients presenting with poor visual acuity (_20/200) have an 80% chance of being left with visual acuity less than 20/200 at final visit, whether the CRVO is ischemic or nonischemic at presentation. Treatments that target the secondary effects of venous occlusion, such as grid laser photocoagulation for macular edema and prophylactic panretinal laser photocoagulation for nonperfused CRVO, were shown to be ineffective in improving visual acuity in the Central Vein Occlusion Study (CVOS). Although panretinal photocoagulation is advocated for reducing the risk of neovascular glaucoma in patients with ischemic CRVO, recent clinical trials have failed to demonstrate any significant benefit with laser photocoagulation in the treatment of macular edema due to CRVO. A number of other treatment options are sometimes used in cases of CRVO, such as oral corticosteroids, intravitreal steroids, vitrectomy, hemodilution, intravitreal tissue plasminogen activator, hyperbaric oxygen, and laser or surgical chorioretinal anastomosis. Studies demonstrating the effectiveness of these treatments are inconclusive, although some benefits have been suggested in recent reports. In recent studies the benefit of antiVEGF agents in improving the macular edema due to CRVO have been shown. In this study we are going to compare the effect of intravitreal antiVEGF (Avastin) with combination of Avastin and Triamcinolon in improving the visual acuity and macular thickness in patients with recent (Less than 6 months) CRVO.

Conditions
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Retinovascular Disease

Intervention / Treatment
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* Drug: Avastin (Bevacizumab) and triamcinolone


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: CRVO with duration less than 6 months Exclusion Criteria: vision less than 20/320 and vison more than 20/50 history of galucoma and diabetic retinopathy previous laser or intravitreal treatment any media opacity that prevents funduscopy

Ages Eligible for Study
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Minimum Age: 40 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

| Intervention/Treatment |
| --- |
|Drug: Avastin (Bevacizumab) and triamcinolone|nan|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Best corrected visual acuity |  |  | 
| Macular thickness by OCT |  |  | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of NVI |  |  | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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CRVO, Intravitreal Avastin, Intravitreal triamcinolone