Description

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After diabetic retinopathy, the varieties of retinal vein occlusion (central, hemi-central, and branch) constitute the most prevalent category of retinal vascular disease. For macular edema associated with central retinal vein occlusion (CRVO), no effective therapy existed until 2009 despite decades of research and failed pilot therapies. In 2009, serial intravitreal triamcinolone therapy was proven to be effective compared to observation. In 2010, a randomized controlled trial reported that laser anastomosis was associated with improved vision relative to observation. For iris neovascularization associated with CRVO, laser panretinal photocoagulation has been proven to be effective at reducing neovascular glaucoma since 1995 and intraocular anti-VEGF drug injections for short term regression of iris neovascularization since 2005. For macular edema associated with branch retinal vein occlusion (BRVO), grid laser photocoagulation was proven to have modest benefits compared to observation since 1988. Sector panretinal photocoagulation for retinal neovascularization associated with BRVO was proven to be effective in reducing vitreous hemorrhage in 1990.

Many proposed surgical therapies including radial optic neurotomy, retinal venous sheathotomy, and vitrectomy with panretinal laser photocoagulation have been piloted and abandoned in the last 20 years because of an excess of adverse side effects or lack of efficacy relative to a treatment benefit.

In the past 5 years, intravitreal injections of anti VEGF drugs have been developed and hold out the promise of improved outcomes compared to the older therapies. Concomitant with these treatment advances has been an improved but incomplete understanding of the underlying pathophysiology of retinal vein occlusions.

About the Author

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Dr. Browning is Retina Specialist at Charlotte Eye Ear Nose and Throat Associates in Charlotte, North Carolina, USA, and is involved with the Diabetic Retinopathy Clinical Research network.