Ocular Migraine - Symptoms, Causes, Diagnosis, and Treatment

What Is Ocular Migraine?

Ocular migraine is any kind of migraine that causes a visual disturbance or blindness for a short duration. It can happen with or without pain, the classic sign of a migraine attack. Some people with migraine get an aura, but less than 20 % of people get an aura in every migraine episode. If any kind of migraine does not cause aura, it is not referred to as ocular migraine. During an ocular migraine attack, people may experience zig-zagging lines, flashing or shimmering lights, or stars. An ocular migraine can interfere with the ability to perform tasks like writing, reading, or driving. The symptoms of ocular migraine are temporary and are usually not considered a serious condition. Ocular migraine should not be confused with retinal migraine, both are extremely different, and the visual disturbance is experienced only in one eye.

What Are the Symptoms of Ocular Migraine?

The symptoms of ocular migraine may vary depending on the individual. However, the common symptoms:

• Ocular migraines can occur suddenly and distort the vision, like a cracked mirror or window or flashes of stars, zig-zag lines, or some other patterns.

• These symptoms are usually threatening but will disappear within 20 to 30 minutes.

• A bright or blind spot may appear in the center of vision and may enlarge and sometimes move across the visual field during the ocular migraine attack.

• Some people may experience silent migraine, which causes some of the visual disturbance of migraine but no head pain.

• Most people suffering from ocular migraine can also experience prodromes (early symptoms indicating the disease's onset) that develop days or weeks before an attack, such as mood swings.

• Slurred speech.

• Nausea and vomiting.

• Headache, which may be pulsating or throbbing.

• Impaired motor skills.

• Sensitivity to light, sound, and smell.

• Numbness or tingling on one side of the body.

What Are the Causes of Ocular Migraines?

The exact causes of ocular migraine are not known. Many theories have been put forward:

• Ocular migraine may be due to inflammation in the brain; the blood vessels swell and exert pressure on nerves, causing pain.

• It may develop because of abnormal electrical activity in the brain's outer surface or cortex, gradually spreading like a wave over the brain's visual area.

• It may be due to the narrowing of arteries causing temporary obstruction of blood flow to the eyes and causing symptoms.

Other factors considered in contributing to ocular migraine include:

1) Genetics

Ocular migraine has an association with a person's genes. According to studies conducted, about 90 percent of people with ocular migraine have a family history of migraine. However, studies have not assessed the exact reason for the inheritance of ocular migraine.

2) Hormone Levels

In females, migraine episodes may be related to the hormonal changes that occur during the menstrual cycle. There may be an association between estrogen levels and migraine. But the exact link between both is not clear. It is most likely due to the low estrogen levels that cause migraine.

Estrogen is a hormone controlling the brain's chemicals associated with pain. Hormone fluctuations in women due to the menstrual cycle, menopause, pregnancy, oral contraceptives, and hormone replacement therapies can contribute to changes in estrogen levels. These changes in estrogen levels may play a key role in migraine symptoms developing.

3) Changes to the Retina

Ocular migraine is largely present with vision changes, so any conditions in and around the eye can play a part in bringing these types of migraine attacks on. It can mainly be caused by blood vessel spasms or blood flow reduction in the retina or the lining behind the eye.

4) Lighting

Too much exposure to unnatural light sources could bring about a migraine attack. Ocular migraine could be triggered if exposed to harsh fluorescent lights or staring at electronic screens for a long time, leading to eye strain.

5) Too Much Time on the Road:

Driving long distances without taking breaks might also trigger an ocular migraine.

6) Triggers:

Some people are more likely to get an ocular migraine or headache after experiencing specific triggers. However, everyone's migraine triggers can differ, but some common ones include:

• Skipping meals.

• Dehydration.

• Weather changes.

• Excessive heat or high altitude.

• Too little or too much sleep.

• Alcohol.

• Excess caffeine.

• Caffeine withdrawal.

• Stress and anxiety.

• Loud noises.

• Strong odors.

• Nitrates contained in deli meats and many prepared meals.

• Tyramine, present in aged cheeses, fava beans, hard sausages, soy products, fava beans, and smoked fish.

• Aspartame.

• Monosodium glutamate (MSG).

• Artificial sweeteners.

How Is Ocular Migraine Diagnosed?

Ocular migraines can be diagnosed by performing a physical examination, taking a clear medical history, and questions regarding lifestyle and medication. A complete eye examination will be carried out, and asking a series of questions will be asked about the symptoms. It is also necessary to rule out other conditions with similar symptoms. Neurologic testing and additional blood test or imaging may be required to rule out other similar conditions.

What Is the Treatment for Ocular Migraines?

The visual portion of ocular migraine usually lasts 20 to 30 minutes, so most people do not get treatment. So during that period of attack, it is recommended to stop the work that a person is doing and provide rest to their eyes until their vision returns to normal. Over-the-counter (OTC) and prescription medications are available for treating recurring migraine episodes. OTC pain medications like Aspirin, Acetaminophen, Ibuprofen, etc., may also help reduce the symptoms. Other medications that help in treating ocular migraine include:

• Beta-blockers like Propranolol or Metoprolol and calcium-channel blockers such as Verapamil and Nicardipine.

• Anti-epileptics such as Valproic acid or Topiramate.

• Antidepressants such as Amitriptyline, Venlafaxine, or Nortriptyline.

Adopting a few lifestyle changes may help reduce the severity and frequency of migraine. These options include:

• Avoiding long screen time.

• Dealing with stress using exercise, acupuncture, relaxation techniques, and biofeedback mechanisms.

• Keep track of symptoms to find the triggers of migraine.

• Reduce weight in case of obesity.

• Eating regular meals.

• Drink enough water.

• Quitting smoking.

• Limit caffeine and alcohol consumption.

• Get adequate sleep.

• Manage anxiety and depression.

Conclusion:

Migraine can impact the quality of life of the affected individual. Ocular migraine causes a visual disturbance or blind spots for a short duration. It can be accompanied with or without migraine symptoms. Diagnosis and treatment are necessary to prevent the onset of a migraine episode. Also, certain lifestyle changes will help in reducing and treating migraine.