Branch retinal vein occlusion
The symptoms of a branch retinal vein occlusion depend on which venous branch is involved. Blurred vision is a common symptom which results from macular edema (swelling in the retina). If the branch retinal vein occlusion occurs at a portion of retina away from the central vision then it may be asymptomatic.

Central retinal vein occlusion
When the central retinal vein is blocked, this will result in more blood and swelling build up in the retina and also worse vision than a branch retinal vein occlusion. Blurred vision is usually due to macular edema or glaucoma from abnormal blood vessels that develop in the eye.

Diagnosis
A dilated fundus examination is usually followed by a fluorescein angiography and optical coherence tomography. A gonioscopy exam is usually performed on patients with central retinal vein occlusion.

Treatment
One of the main complications of vein occlusion is macular edema, which is swelling in the central part of the retina. Injections of anti vascular endothelial growth factor and steroids may help treat macular edema.
In severe cases of central retinal vein occlusion, abnormal blood vessels may develop in the eye. Laser treatment is needed and sometimes vitrectomy surgery or glaucoma surgery may be necessary if the problem becomes more severe.

Most retinal vein occlusions occur after the age of 50, younger patients with retinal vein occlusion may be asked to see their internist for a thorough medical evaluation.