BRANCH RETINAL VEIN OCCLUSION

A branch retinal vein occlusion is also known as a BRVO.

The entire body contains multiple arteries, which bring oxygenated blood circulation from the heart to all body organs and tissues as well as multiple veins that carry deoxygenated blood circulation back to the heart.  Arteries and veins also play an important function in the eye.

A branch retinal vein occlusion, or BRVO may occur in a branch of the main vein in the eye.  When a BRVO occurs, there is reduced blood flow in a branch of the main vein causing the outflow of ocular blood circulation to be reduced, or to possibly stop altogether.  When a BRVO occurs and the circulation is poor or absent, the blood flow is blocked, almost like a traffic jam.  Blood and fluid may then leak out of the vein and cause macular swelling or edema causing vision loss.

What are the symptoms of a branch retinal vein occlusion?

The symptoms of a branch retinal vein occlusion, or BRVO most often occur in one eye.  When experiencing a BRVO, a person may notice gradual or sudden vision loss in one eye.  Central vision may be blurred or absent, floaters or dark spots may obscure vision.  A blurry or dark area (scotoma) may affect the upper or lower margins of vision.

What are the causes and risk factors of a branch retinal vein occlusion?

Sometimes, a branch retinal vein occlusion happens spontaneously without cause.    However, a blood clot, narrowed blood vessels, or high pressure in the eye caused by a thickened artery crossing over a vein (arteriosclerosis) are often the cause.

Artery walls may be compared to pipes as they are thicker and heavier.  Vein walls can be compared to garden hoses as they are more flexible.  When the artery hardens and presses on top the vein, reduced blood circulation in the vein may occur causing poor or absent blood flow, thus causing a branch retinal vein occlusion.

A fluorescein angiogram image noting an ischemic superotemporal branch retinal vein occlusion with clinically significant macular edema.

Risk Factors include:

  • High blood pressure
  • Diabetes
  • Glaucoma
  • Arteriosclerosis (hardening of the arteries)

To lower the risk for branch retinal vein occlusion:

  • Eat a low-fat diet
  • Maintain an ideal body weight with BMI controlled
  • Maintain a weekly exercise regimen
  • Don’t smoke

What can I expect at a branch retinal vein occlusion screening at Retinal Associates of Greater Philadelphia?

After a comprehensive, dilated eye examination is performed by the ophthalmologist, a series of diagnostic tests may be ordered to better evaluate the health of your retina.  These tests include, but are not limited to:

The physician may also order alternate tests to evaluate blood sugar levels as well as cholesterol levels to identify the cause of a central retinal vein occlusion.

How is a branch retinal vein occlusion treated?

There is no absolute cure for a branch retinal vein occlusion.  However, the retinal specialist will coordinate a plan of care with the primary care provider, or referring physician to aid in the diagnose and cause of the vein occlusion.  The arteries and veins have a circuit throughout the entire body.  If there is concern in the eye, there may be concern for overall health of the body.  Therefore, a work up of body systems may benefit overall health as well as eye health.

Treatments for branch retinal vein occlusions include:

FOCAL LASER THERAPY
Focal laser therapy, or photocoagulation therapy may be used to stop or slow the progress of macular edema from a branch retinal vein occlusion.  The ophthalmologist utilizes a laser light beam targeting selected blood vessels of concern with precision.  Small, superficial, laser burns are applied to these vessels in order to preserve further bleeding, or fluid (edema), while leaving the surrounding, healthy tissue untouched.  This procedure is done in the office.

ANTI-VEGF THERAPY
Vascular endothelial growth factor, or VEGF is a molecule generated by the body that causes new blood vessels to grow. Sometimes this is normal, however, in retinal disorders such as macular edema from branch retinal vein occlusions, a higher level of VEGF causes abnormal blood vessels to grow. The abnormal vessels leak fluid or blood causing distortion of vision. Injections of anti-VEGF drugs into the eye block the activity of VEGF and often result in a decrease in the fluid or bleeding caused by the abnormal vessels. This procedure only takes moments and is done in the office.

Your ophthalmologist will discuss with you which course of treatment is best for you.

ANTI-VEGF MEDICATION TREATMENT