Amaurosis fugax

Conditions

Amaurosis fugax is a condition in which a person’s eyes do not get enough blood flow, and they cannot see out of one or both eyes. 

The disease is a symptom of an underlying problem, such as a blood clot or insufficient blood flow to the blood vessels that supply the eye. 

Amaurosis fugax is also called transient monocular blindness, transient monocular visual loss, or temporary vision loss.

What are the symptoms of fleeting amaurosis?

When a person has fleeting amaurosis, their vision may suddenly appear clouding. This temporary effect can last from a few seconds to several minutes. 

Often, fleeting amaurosis is a symptom of transient ischemic attack (TIA). 

Other symptoms associated with transient ischemic attacks include temporary blindness, difficulty speaking, drooping on one side of the face, and sudden weakness on one side of the body.

The causes

Amaurosis occurs when blood flow is blocked to the central retinal artery that supplies blood to the eyes. A common cause of fleeting amaurosis is a blockage of blood flow to the eye by a piece of atherosclerotic plaque or a blood clot.

Risk factors include a history of heart disease, high blood pressure, high cholesterol, smoking, or alcohol or cocaine abuse.

Other underlying causes of the disease include:

  • brain tumor
  • head injury
  • history of multiple sclerosis
  • history of lupus erythematosus
  • migraine
  • optic neuritis, which is inflammation of the optic nerve

Transient amaurosis can be caused by diseases that affect the nervous system and blood flow to the head. Other possible causes include temporary blindness due to vasospasm, in which the blood vessels in the eye suddenly constrict, restricting blood flow. Strenuous exercise, running, and sexual intercourse can all cause vasospasm.

What are the treatments?

Treatment for amaurosis fugax involves identifying and treating the underlying medical condition. If the disease is linked to high cholesterol levels or blood clots, this indicates that a person is at increased risk for stroke. 

Treatments include:

  • Blood thinners, such as aspirin or warfarin (Coumadin);
  • surgery is known as carotid endarterectomy, in which a doctor will ‘clean out’ plaque potentially blocking the carotid arteries;
  • medicines to lower blood pressure.

In addition to these medical treatments, a doctor will recommend non-drug treatments:

  • abstain from eating foods high in fat, such as fried, processed, or fast foods,
  • stop smoking;
  • exercise at least 30 minutes a day most days of the week;
  • manage chronic diseases like diabetes, high blood pressure, or high cholesterol.

How is amaurosis diagnosed?

Your doctor will then perform a physical exam, including an eye exam. Your doctor may also order tests, which may include:

  • imaging scans to identify blockages or damage to blood vessels in your eyes;
  • blood tests to determine your cholesterol level as well as the likelihood of blood clotting;
  • an electrocardiogram to identify irregularities in your heartbeat that could lead to fleeting amaurosis.

A doctor will consider your symptoms, age, and general health when diagnosing amaurosis and temporary vision loss.

What are the complications of amaurosis?

Although amaurosis is a short-lived condition that causes symptoms that last from a few minutes to an hour, it is often a worrying indicator of an underlying disease. 

This includes an increased risk of stroke, which can be fatal. If people ignore these signs, they are at risk for more severe complications.

What is the prognosis of amaurosis?

Amaurosis is a concerning symptom, as it may indicate a high likelihood of a person having a stroke.

In the case of transient ischemic attack, the earlier the disease is treated, the fewer serious complications there will be.