Retinal Artery Occlusion

We specialize in the medical and surgical treatment and management of sight threatening diseases affecting the retina, vitreous and macula.  We have years of experience in treating the following conditions.


Retinal Artery Occlusion

fluorescein angiogram of retinal artery occlusion 
fluorescein angiogram of retinal artery occlusion
fundus photo of retinal artery occlusion  
fundus photo of retinal artery occlusion

What is a Retinal Artery Occlusion?

The retina is a specialized layer of nerve tissue that coats the back of the eye and is responsible for helping you to see. A retinal artery occlusion occurs when blood flow in one of the arteries that feeds the retina is reduced or blocked. Because of the lack of oxygen in the retina, permanent severe vision loss can occur.

What causes a Retinal Artery Occlusion and who is at risk?

There are many different causes for a retinal artery occlusion, and causes vary depending on the patient. The cause of a retinal artery occlusion may be discovered through a general medical evaluation; however, sometimes the source of a retinal artery occlusion cannot be identified. It is known that this condition typically occurs in individuals greater than 50 years old. The most common reason for the blockage is a small blood clot breaking off from around the heart or from a blood vessel in the neck and traveling to the eye. Some diseases may increase your risk for developing a retinal artery occlusion, such as irregular heart beat (atrial fibrillation), narrowing of the arteries in the neck (carotid stenosis), heart disease, and blood clotting disorders.

What are the different types of Retinal Artery Occlusions?

There are two major categories of retinal artery occlusions, branch and central retinal artery occlusions. The arterial system supplying blood to the eye can be compared to a tree in that it has one large trunk (central retinal artery) feeding smaller and smaller branches (branch retinal arteries). In a branch retinal artery occlusion (BRAO) a small branch of the retinal artery system becomes blocked, while central retinal artery occlusion (CRAO) is characterized by a blockage in the primary trunk.

What are the symptoms of a Retinal Artery Occlusion?

The most common initial symptom is a sudden, painless loss of vision. In a CRAO the vision loss is usually very severe to the point where most people are not able to read any letters on the eye chart. On the other hand, the amount of vision loss in a BRAO depends on the size and location of the blockage. For example, often only a part of the peripheral or central vision is affected in a BRAO.

How is a Retinal Artery Occlusion diagnosed?

Your retina specialist can diagnose an artery occlusion by examining your eye and using specialized testing to such as a fluorescein angiogram and optical coherence tomography to confirm the diagnosis and evaluate the extent of the blockage. A photographic dye test called a fluorescein angiogram can be used to identify the location of blockage and the extent of the loss of blood flow, while an optical coherence tomography (OCT) is used to obtain a high-resolution anatomic scan of the retinal structure.

What further testing needs to be done?

It is important to try and identify the reason for the artery occlusion. This is because it is possible that the underlying problem that caused the first artery occlusion could cause new artery occlusions in the other eye or elsewhere in the brain (a stroke). Different tests may be ordered depending on the specific patient and their history, however most patients need to have blood work, an echocardiogram (ultrasound of the heart) and a carotid Doppler (ultrasound of the vessels in the neck).

What are the complications of Retinal Artery Occlusions?

In severe cases of retinal artery occlusion where the retina does not get enough oxygen, abnormal blood vessels can grow inside the eye (neovascularization). These new blood vessels are very problematic because they tend to bleed. In severe cases bleeding can occur in the vitreous cavity or severe glaucoma can develop from the blood vessels growing near the front of the eye. Left untreated, these changes can result in irreversible blindness.

How is a Retinal Artery Occlusion treated?

The goal of treatment is to rapidly open the artery that has the blockage. Unfortunately, the retina usually is irreversibly damaged when it does not get the oxygen and nutrition that it needs for just a short time. Many treatments have been described but there are no good treatments for retinal artery occlusions. Some of the symptoms, such as high eye pressure, may be treated with eye drops, since lowering the eye pressure sometimes helps relieve the arterial occlusion. For CRAO, vision loss is usually severe, with most people not able to read anything on the eye chart. However, in a small percentage of people, part of the central vision remains with good blood flow and a small central island of vision can remain. The visual field loss associated with a BRAO is usually permanent. If the part of the retina responsible for the central vision is unaffected the vision can remain good.


Highland Retina Associates

  • Highland Retina Associates - 4621 E Margaret Dr., Terre Haute, IN 47803 Phone: (812) 281-2608