What is a retinal vein occlusion?
The retina is nourished by tiny blood vessels that bring blood into (arteries) and out of (veins) the eye. Occasionally an artery will compress the underlying vein, making it difficult for blood to exit the eye. This blockage, called a branch retinal vein occlusion, causes the vein to dilate and leak fluid and blood. The main vein exiting the eye can also become blocked within the optic nerve, causing a central retinal vein occlusion. Retinal vein occlusions are more common in older individuals as well as persons with hypertension, diabetes, or glaucoma but can occur in young healthy individuals.Macular edema (swelling) develops when the occlusion involves the macula, causing it to swell with fluid and blood. Central vision can become blurred, just like a water droplet placed on a photograph will cause the picture to blister and become distorted.
Retinal vein occlusions can also decrease the overall retinal blood supply. Some eyes will develop tiny new blood vessels along the retinal surface in an attempt to increase the retinal blood supply (retinal neovascularization). These new vessels do not help the eye, however. They are fragile and can cause blindness by hemorrhaging or retinal detachment. Retinal neovascularization develops in about 25% of eyes with branch retinal vein occlusions and rarely in eyes with central retinal vein occlusion.
What are the symptoms of a retinal vein occlusion?
Retinal vein occlusions can cause blurring of the central and peripheral vision. Central retinal vein occlusions generally cause more severe loss when compared to branch retinal vein occlusions. .How is a retinal vein occlusion diagnosed?
You can't diagnose a retinal vein occlusion by looking in the mirror since your eye will usually look and feel normal. The diagnosis is made with a thorough retinal examination through a dilated pupil. Additional testing, including OCT scanning and fluorescein angiography, may be performed to better diagnose and assess the need for treatment.What treatments are available for retinal vein occlusions?
Eye injections (intravitreal) with anti-VEGF medications (Avastin, Lucentis, Eylea or Beovu) is the most common form of treatment.Laser therapy and steroid injections may be used in select cases.