Causes Of Retinal Vascular Occlusion: Symptoms And Treatment

Retinal vascular occlusion is blockage in the arteries and veins supplying blood to retina. Retina is a thin layer at the hind of the eye. It is a light sensitive membrane consisting of rods and cones cells. They are typical cells which convert light into signals. These signals are carried by the optic nerve attached to the retina to the brain. Brain analyses and converts it into an image. Thus any problem with retina affects vision.

The vascular system just as anywhere else in the body supplies blood and vital nutrient to retina through retinal arteries.

Retinal veins carry waste produced by retina. Obstruction in any of these vessels can affect visual acuity and sudden loss of vision. This condition of eye is uncommon in young adults but most often develops in elderly people.

Types Of Retinal Vascular Occlusion

There are two types of retinal vascular occlusion, namely arterial occlusion and venous occlusion. In retinal arterial occlusion the blockage can occur in the main artery which carries oxygen rich blood to the retina. If the obstruction is in the main artery it is called central retinal arterial occlusion. Blockage can also occur in the branch artery.

Blockage can also develop in the vein carrying blood and waste products from the retina towards the heart. If the main retinal vein is affected it is called central retinal venous occlusion whereas if some branch is obstructed it is called branch retinal venous occlusion. Since more blood is carried by the main vessel, any obstruction in it can be more damaging than blockage in branch vessels.

Causes And Risk Factors For Retinal Vascular Occlusion

The exact cause of retinal blood vessel blockage is not yet clearly established. The two more prominent causes that can be considered are narrowing of the blood vessels or obstruction from a blood clot.

Wide varieties of risk factors can be implemented such as:

  • Atherosclerosis of the arteries. It is hardening and constriction of the arteries caused due to formation of fatty plaques.
  • Narrowing of blockage of the carotid arteries. Carotid arteries are the main arteries in the neck that supply blood from the heart to head and neck area.
  • High cholesterol level in blood.
  • High blood pressure.
  • Being elderly and above the age of 40.
  • Diabetes mellitus
  • Obesity
  • Glaucoma
  • Smoking
  • Blood disorders
  • Autoimmune diseases such as systemic lupus.
  • People suffering from obstructive sleep apnea are at greater risk.

Symptoms Of Retinal Vessel Occlusion

The symptoms of retinal vascular occlusion can be sudden and obvious or may be subtle. In majority of cases only one eye is affected. Here are following symptoms noted in this condition:

  • Sudden change in vision from normal to blurry vision.
  • There can be partial or complete loss of vision in many cases.
  • There is no pain in the eye.
  • Vision loss can be progressive staring from few hours to few days.
  • In some cases there is sudden and complete loss of vision.
  • Change of vision can last for a short term or may persist indefinitely. This will depend on how quick patient starts taking treatment.

Treatment For Retinal Vascular Occlusion

There is no medication or any other way to unblock the retinal vascular occlusion. Doctors will try to treat the condition with certain treatment measures. In some patients there may be improvement in vision while some patients improve gradually but with some defect always remaining. The outcome may be known only after one year.

Medicines for retinal vein occlusion may include use of anti-vascular endothelial growth factor (anti-VEGF) drugs. This drug is injected into the eye. Doctors also use corticosteroids to combat swelling. Often laser therapy is also used to control swelling and edema in the retinal area.

The best way to prevent retinal vascular occlusion is to stop smoking, losing weight if obese, eating healthy food and exercising to reduce incidence of high cholesterol in blood. Control of diabetes is also essential part of treatment in diabetic patients.