Arteries and veins carry blood throughout your body, including your eyes. The eye’s retina has one main artery and one main vein. When branches of the retinal vein become blocked, it is called branch retinal vein occlusion (BRVO).
When the vein is blocked, blood and fluid spills out into the retina. The macula can swell from this fluid, affecting your central vision. Eventually, without blood circulation, nerve cells in the eye can die and you can lose more vision.
What Are the Symptoms of BRVO?
The most common symptom of branch retinal vein occlusion (BRVO) is vision loss or blurry vision in part of the eye. It can happen suddenly or become worse over several hours or days. Sometimes, you can lose all vision suddenly.
You may notice floaters. These are dark spots, lines or squiggles in your vision. These are shadows from tiny clumps of blood leaking into the vitreous from retinal vessels.
What Causes BRVO?
Many times doctors don’t know what causes the blockage in BRVO. Sometimes it can happen when disease makes the walls of your arteries thicker and harder. Those arteries can cross over and put pressure on a vein.
Who Is at Risk for BRVO?
Branch retinal vein occlusion (BRVO) usually happens in people who are aged 50 and older.
People who have the following health problems have a greater risk of BRVO:
To lower your risk for BRVO, you should do the following:
- eat a low-fat diet
- get regular exercise
- maintain an ideal weight
- don’t smoke
How Is BRVO Diagnosed?
Your ophthalmologist will widen (dilate) your pupils with eye drops and check your retina.
They will also do a scan of the retina called optical coherence tomography (OCT) to look for swelling, which affects vision.
They may do a test called fluorescein angiography. Yellow dye (called fluorescein) is injected into a vein, usually in your arm. The dye travels through your blood vessels. A special camera takes photos of your retina as the dye travels throughout the vessels. This test shows if any retinal blood vessels are blocked.
Also, your blood sugar and cholesterol levels may be tested.
People under the age of 40 with branch retinal vein occlusion (BRVO) may be tested to look for a problem with their blood clotting or thickening.
How Is BRVO Treated?
With branch retinal vein occlusion (BRVO), vision usually worsens due to swelling of the macula. The main goal of treatment is to dry up the retina. In most cases, medication or laser help reduce fluid and swelling.
Your ophthalmologist may also choose to treat your BRVO with medication injections in the eye. The medicine can help reduce the swelling of the macula. These injections are a type of medicine called “anti-VEGF.” They can improve vision in about 1 of 2 patients who take them. Because swelling in the retina returns after medicine wears off, injections must be taken regularly for for the benefit to last..
Your ophthalmologist may do a form of laser surgery called focal laser treatment. A laser is used to make tiny burns to areas around the macula. This helps stop fluid from leaking from the vessels.
While most people see some improvement in their vision, some people won’t have any improvement. However, keeping the retina dry for those without improvement may help prevent vision loss in the future.
For those who don’t show improvement with anti-VEGF, steroid injections or steroid implants may be an option. The steroid implant can improve vision in close to a third of people with BRVO.