Modalities of Treatment of Retinal Vein Occlusion

Abstract

SUMMARY R etinal vein occlusion is an eye condition commonly seen by ophthalmologists. It is second to diabetic retinopathy as a cause of visual loss due to retinal vascular disease. There are two forms of retinal vein occlusion, branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO). The nonischemic type is able to maintain better relative blood flow to the retina through collaterals, preventing the dreaded complications known of the ischemic type. Different modalities of treatment Medical Care Intravitreal injection of triamcinolone Used to treat macular edema of different etiologies because of its potent antipermeability and anti-inflammatory properties. Doses from 4 mg to 25 mg have been reported to be effective. Multiple doses appear to be needed. Reinjections (if needed) will be performed beginning at 4 months after the initial therapy requiring repeat typically every 3-6 months. Intravitreal injection of 4 mg of triamcinolone improved the mean best corrected visual acuity by 2.5 lines at 12 months of follow-up. Patients will be followed for up to 3 years to measure long-term treatment efficacy and safety triamcinolone injections. Intravitreal injection of bevacizumab In patients with macular edema, injection of bevacizumab (0.05 mL/1.25 mg) has been shown to be effective in resolving the edema and improvement in vision. Injections of bevacizumab given every 6 weeks for 6 months improve visual acuity and significantly reduce edema. Also, in patients with neovascular glaucoma, a similar dose has shown significantly decreased angle neovascularization. The main drawback of these injections is post treatment recurrences of macular edema, requiring repeat injections. Intravitreal injection of ranibizumab Intraocular injections of 0.3 mg or 0.5 mg ranibizumab provided rapid improvement visual acuity and macular edema in 6-month. LUCENTIS is recommended to be administered by intravitreal injection once a month. Although, treatment may be reduced to one injection every three months after the first four injections. Long-term follow-up of these patients is needed to know the persistence of these gains for more than 6 months. Dexamethasone intravitreal implant It is available as a 0.7 mg implant and indicated for the treatment of macular edema following BRVO or CRVO. The drug-copolymer complex gradually releases the total dose of dexamethasone over a series of month. A 6-month study evaluated the safety and efficacy of dexamethasone implant. The results of the study demonstrated that the dexamethasone implant reduced the risk of further vision loss and increased the chance of improvement in visual acuity in eyes with CRVO.