Retinal vein occlusion is the second most common cause of blindness due to retinal vascular disease after diabetic retinopathy.
Retinal vein occlusion is a common eye problem. A major cause of retinal vein occlusions is arteriolosclerosis or the thickening of the blood vessel walls. Thickening of the walls of your blood vessels occurs in response to increased blood pressure. This arteriolosclerosis leads to a compression of the ocular veins which course under the arteries. This compression leads to partial occlusion of the vein, development of a blood clot, and damage to the blood vessel wall. When blood cannot drain properly, it leads to bleeding and leakage of fluid from blocked blood vessels. Oxygen delivery to the retina is reduced and problems such as blurred vision, blind spots, bleeding in the eye, or a painful type of glaucoma can ensue.
What causes a retinal vein occlusion?
Risk factors for retinal vein occlusion include age (your risk increases 10-fold from age 40 to age 65), hypertension, high cholesterol, diabetes, or elevated eye pressure. In the rare cases where retinal vein occlusion is not explained by these factors, lab work must be done to search for other, uncommon medical conditions that lead to an increased tendency for blood to clot.
What does RVO mean?
Ophthalmologists use different terminology to describe retinal vein occlusions, depending on where the blockage in the eye occurred. A BRVO, or branch retinal vein occlusion, occurs in one of the smaller veins in the eye. A BRVO may only affect one-quarter or one-half of the retina, leaving other parts of the retina to function normally. In contrast, a CRVO, or central retinal vein occlusion, affects the main venous drainage of the eye. Typically, a central retinal vein occlusion is more severe than a BRVO, and patients experience worse vision and develop more complications due to the poor blood flow patterns that result due to the blockage of the main drainage of the eye.
What is your ophthalmologist looking for?
When a retinal specialist looks inside your eye, he can see vessels which are wider and curvier than normal. This finding indicates your vessels may have increased pressure due to an outflow problem which occurs in any vein occlusion. The doctor will see many hemorrhages occurring within the retinal layers. In addition, a swollen optic nerve and swelling in the central retina are often found. Additional testing (e.g. optical coherence tomography and fluorescein angiogram) done by your retinal specialist can further determine the level of retinal swelling and show how the vein occlusion has affected the blood flow to the eye.
Here is a patient who has suffered a branch retinal vein occlusion.
Look at this patient who has suffered a more severe central retinal vein occlusion.
What are symptoms of burst blood vessels in your eye?
Patients who suffer a vein occlusion usually report a sudden or gradual onset of blurred vision or blind spots. In the case of a central retinal vein occlusion, the vision loss can be severe and frightening. Vein occlusions usually occur in one eye at a time. If left undiagnosed, eye pain and discomfort can result as a complication of the vein occlusion due to the development of a potentially painful, more rapid type of glaucoma (neovascular glaucoma or NVG).
An examination by a good ophthalmologist is necessary to establish a diagnosis and to recognize when complications arise. The two most common vision-threatening complications are macular edema (build-up of fluid in the retina responsible for central vision) or neovascularization (new blood vessel growth related to poor oxygen availability). Both conditions are impossible to detect without a comprehensive eye exam. Both require ongoing treatment with a good retina specialist.
Can retinal vein occlusions be cured?
Ophthalmologists can’t undo the blockage once it already has occurred. Working with retinal specialists, steps are taken to identify and treat complications. Good treatment options include careful observation, focal laser, panretinal photocoagulation (PRP), or eye injections (Avastin, Lucentis, or Eylea). The medical conditions that may have led to a retinal vein occlusion need to be addressed to prevent a similar event in the other eye. If you’ve had a vein occlusion in one eye, you have approximately a 10% chance of having a new vein occlusion in the other eye.
Vein occlusions are a sign of blood vessel damage that is occurring in the body. Taking steps to prevent blood vessel damage, in general, may reduce the risk of retinal vein occlusions, strokes, and heart attacks. These measures include eating a healthy diet, maintaining a healthy weight, not smoking, exercising regularly, and controlling your blood pressure and blood sugar. Ophthalmologists commonly work with your family physician to lower your risks for blood vessel damage due to chronic medical conditions that raise your risk for retinal vein occlusions (diabetes, hypertension, high cholesterol, etc.)
How will my vision be affected by a retinal vein occlusion?
Visual prognosis depends on the severity of the retinal vein occlusion and how poor the resulting blood flow in an eye becomes. Due to advancements in modern medicine, this is no longer a “death sentence” for an eye. Studies have shown, with good treatment, many patients can preserve good vision.
What should I do now if I am worried about retinal vein occlusion?
Retinal vein occlusions are a common eye problem. Prompt diagnosis under the care of a good retina specialist can help you avoid many of the complications of retinal vein occlusions. If you are experiencing any new eye symptoms or think you may have suffered a vein occlusion, call today 941-777-5000!
For more reading, check out the Preferred Practice Pattern from the American Academy of Ophthalmology.
All the best,
Chris Stelton, MD