Retinal Vascular Occlusions can occur at anytime. The retina—the layer of light-sensitive cells at the back of the eye—is nourished by network of fine blood vessels, which constantly provide nutrients and oxygen, and remove its waste byproducts. Retina arteries supply the nutrient and oxygen to the retina while retina veins remove the waste products and deoxygenated blood away from the eye. It is important that both arteries and vein are properly flowing at all times.
A blockage in the arteries can result in a devastating and sudden vision loss either involving complete or partial fields of vision. Artery occlusion is a serious condition, because it is often associated with general atherosclerosis ( changes in the blood vessels due to cholesterol) which can cause stroke and heart attack. Time is of essence, as the retina tissue suffers irreversible loss of function as early as 90 minutes after such blockage. Complete medical and cardiovascular evaluation with special attention at lowering risk factors of heart attack and stroke can often be life saving in such cases.
Blockage in retina veins can cause partial or total vision loss as well. Such blockage is often seen in a setting of High Blood Pressure and or Diabetes. The blockage of the retina veins disturbs normal blood flow which results in damage to the retina cells. It also causes the walls of the remaining veins to leak fluid. If the area of leakage is close to the center of the retina ( macula), further vision loss occurs due to macular edema.
Treatment of retinal vein occlusion is a team effort. First and foremost, controlling High Blood Pressure and Diabetes will help the general healing process tremendously. An updated complete medical evaluation and optimization by the medical team is extremely helpful. There are many treatment options available for the vein occlusion. The retina specialists may offer focal or complete retina laser in order to seal leaky blood vessels. Another treatment option involves intravitreal injections ( injections of medicine to the back of the eye) of Avastin, Lucentis, Eylea and Triesene. Although such injections may be repeated over few months or longer, they can often result in visual improvement.