Retinal Vein Occlusion
A retinal vein occlusion occurs when hardened arteries pinch a vein, or blood clotting in a vein causes blood flow to be impeded. Subsequently, blood flow is impeded out of the eye causing leakage and swelling in retinal tissue. This can lead to retinal stress, hemorrhage, and damage as oxygen and other nutrients are not adequately delivered.
Types of RVO
There are two main categories of vein occlusion: branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO). BRVO is occlusion of a segment of the retinal venous system, while CRVO is occlusion of the entire retinal venous system. Some mild BRVOs are insignificant and don’t cause symptoms while some severe forms of CRVO can lead to total blindness in an eye.
Central Retinal Vein Occlusion (CRVO)
Branch Retinal Vein Occlusion (BRVO)
CRVO & BRVO Fact Sheets
Download one of the following documents to learn more about central retinal vein occlusion (CRVO)and branch retinal vein occlusion (BRVO).
PDF Fact Sheet (CRVO)
Large-Print Version (CRVO)
PDF Fact Sheet (BRVO)
Large-Print Version (BRVO)
Spanish Translation (BRVO)
Risk Factors, Causes, & Symptoms
The main risk factors for retinal vein occlusion are age, diabetes, high blood pressure, cigarette smoking, and glaucoma. Retinal vein occlusions usually occur in people over the age of 55. If an occlusion occurs in a young patient without identifiable risk factors, a workup for a blood disorder or sleep apnea may be indicated. In vein occlusions, patients generally notice loss of central or peripheral vision depending on the location of the occlusion. Symptoms can come on suddenly, or develop gradually and worsen over days, weeks, or months.
While eye specific treatment is usually indicated and beneficial, without good control of high blood pressure, diabetes, etc., chances of achieving and maintaining good vision are small. Control of systemic diseases is also critical for reducing the risk of a recurrent vein occlusion. If the vein occlusion is causing swelling of the macula (the area of the retina responsible for central vision), retinal treatment involving injection of medicine directly into the eye is usually indicated.
Medicines injected into the eye are inhibitors of “bad molecules” which are overproduced by the eye in vein occlusion disease. While injections into the eye can sound scary to a patient, most say that talking about it is worse than having it. There are no restrictions after one of these injections, though patients can expect some eye irritation that should be manageable with over-the-counter artificial tear drops. Injections into the eye are not a “cure” but can manage the disease quite effectively in many situations. In clinical trials of these injections, patients usually experienced improvement or stability with monthly injections for at least 6 months. Injections may be required at regular intervals (4-6 weeks) for some time, but may not need to continue forever.
Laser may also be necessary in the treatment of vein occlusions. Laser is usually employed in situations where the occlusion is severe and abnormal blood vessels (neovascularization) begin to grow and hemorrhage into the eye; this is a situation which can require laser in the office, or even operating room surgery in very severe cases.
In summary, retinal vein occlusion usually occurs in people over the age of 55 who have diabetes, high blood pressure, glaucoma, or a history of cigarette smoking. The condition can cause blindness, but can be effectively treated by a Colorado Retina surgeon in coordination with a primary care doctor. In addition to the ocular treatments described above, proper management of systemic disease (diabetes, high blood pressure, cholesterol, etc.) will reduce the risk of further vision loss in the future.