Ocular migraines: Symptoms, treatment and prevention
What is an ocular migraine?
Ocular migraines usually cause temporary vision loss or distortion in one eye, usually accompanied or followed by a headache. They are also called retinal migraine, eye migraine or ophthalmic migraines.
Ocular migraines are caused by a sudden tightening (or constriction) of blood vessels, which reduces blood flow to the eye. Most last under five minutes. Afterwards, vision usually returns to normal.
Although frightening, ocular migraines are typically harmless. Most people recover fully. They can sometimes cause damage to the retina and its blood vessels. Permanent vision loss is quite rare.
Ocular migraines may be more common in
- People under 40 years old
- People who have a personal or family history of migraines or other headaches
- People who have diseases such as lupus, hardening of the arteries, sickle cell disease, epilepsy or depression.
The term ‘ocular migraine’ is used in different ways, which can cause confusion. More common migraines with auras - which also cause visual distortions - are sometimes described as ‘ocular migraines’, especially if they don't cause a headache.
The difference between these two types of migraine is that ocular migraines only cause symptoms in one eye, while migraines with aura affect both.
Since the term can have very different meanings, you should be careful. If you are diagnosed with an ocular migraine, make sure you understand how your doctor is using the term.
Symptoms of ocular migraines
Some ocular migraines cause temporary but complete vision loss in one eye. In other cases, ocular migraines can cause vision disturbances like:
- Partial vision loss
- Scotomas, or blank spots in your vision
- Flashes of light
Ocular migraines are usually brief, lasting less than one hour. Some people have a headache during the vision loss, others have it before or after.
Diagnosing ocular migraines
If you get to the doctor during an ocular migraine, he or she will be able to see the decreased blood flow in your eye with a device called an ophthalmoscope or fundoscope. However, since ocular migraines are fairly brief, it's more likely that you will be diagnosed based on your symptoms.
The symptoms of ocular migraines are similar to those of other serious disorders, like eye diseases and stroke. So your doctor will want to do a thorough evaluation. If you:
- Have no history of migraines
- Are over 50
- Have cardiovascular disease.
Your doctor may perform additional tests to rule out more serious conditions.
Ocular migraine treatment
Since it is brief, the vision loss of ocular migraines is not usually treated, but you may need relief for the headache that accompanies or follows it.
The primary treatment for ocular migraines is to reduce exposure to triggers.
Ocular migraine prevention
The first step to preventing migraines is to avoid triggers. These often include:
- High blood pressure
- Hormonal birth control pills
- Bending over
- High altitude
- Low blood sugar
- Excessive heat
Dietary triggers - such as caffeine, alcohol and artificial sweeteners - can cause other types of migraine, but they seem less likely to trigger ocular migraines.
Drugs can also prevent ocular migraines. These include anti-convulsants, anti-depressants, anti-inflammatories, and drugs used to treat high blood pressure.