What is Ocular Migraine, and is it a Symptom of COVID-19?

What is ocular migraine?

The term “ocular migraine” is often used to refer to any type of headache that causes visual changes. Sometimes it’s used to specifically refer to a type of migraine called retinal migraine.

Retinal migraine

Retinal migraine is a condition that causes partial or full vision loss in one eye and a headache within 60 minutes of vision loss.

The reason why these migraine episodes develop is controversial. Some researchers point to a possibility that a narrowing of the retinal or ciliary arteries causes them. Other researchers suggest electrical changes in the neurons of the retina cause them.

Partial or total vision loss typically lasts 10 to 20 minutes before returning to normal. Your vision may also become blurry or dim. You may experience flashes or mosaic patterns of light.

As of now, there’s no research connecting this specific type of migraine to COVID-19.

Migraine aura with visual disturbance

Migraine is a neurological condition that often causes intense headaches. Migraine tends to run in families.

A migraine aura is experienced by about 25 percent of people with migraine, either before or at the same time as a migraine episode.

Usually, people who have migraine with aura don’t experience an aura with all of their migraine episodes, just with some of them.

An aura is a temporary visual, auditory, motor, or other sensory change. Visual disturbances can include:

• seeing a blind spot
• seeing flashes of light
• vision loss
• kaleidoscope vision

Among people who experience an aura, about 99 percent have at least one visual symptom with some of their auras.

Is ocular migraine a symptom of COVID-19?

Some people with a previous history of migraine report worsening migraine episodes during COVID-19. Some people without a history of migraine report experiencing migraine-like headaches.

A 2020 study found that among 47 people with COVID-19 who reported having headaches, 24 people (51 percent) reported migraine-like headaches, while 40 percent had symptoms of a tension headache.

Before they developed COVID-19, only 12 of the study participants had previously experienced migraine episodes.

Severe neurological complications such as stroke or seizure have also been reported, although these aren’t common with COVID -19.

The most common eye symptoms were:

• dry eyes or foreign body sensation
• redness
• tearing
• itchiness
• eye pain
• discharge

What does the research say?

Researchers are still trying to figure out how the virus that causes COVID-19 interacts with our nervous system. Some people with a history of migraine report an increased frequency or intensity of migraine episodes during COVID-19.

A May 2021 study highlights three case studies of people with a history of migraine who experienced migraine episodes during COVID-19.

In two of the people, migraine with aura was the initial symptom of COVID-19. The third person developed visual auras at the same time as other COVID-19 symptoms.

Here’s a summary of the migraine symptoms the three people experienced before and during COVID-19 illness:

Why might COVID-19 increase migraine frequency or intensity?

Research has found that parts of the trigeminal nerve lack the protective blood- brain barrier that helps prevent microorganisms from entering the central nervous system.

Autopsy studies have found evidence of degeneration of the trigeminal nerve in people with COVID-19, suggesting either direct damage from the coronavirus or damage from the body’s immune response.

The coronavirus is thought to enter cells in your body through receptors for the enzyme called angiotensin converting enzyme 2 (ACE2). ACE2 receptors have been found in neuron cells in the trigeminal nerve as well as many other parts of the body.

Effects of the pandemic on people with migraine

Various factors related to the COVID-19 pandemic unrelated to direct viral infection may have led to increased migraine frequency or severity in some people.

Factors such as lack of communication with a neurologist and increased stress may have played a role.

Only 4 percent of the study participants developed COVID-19, but of those people, 63.4 percent reported their migraine worsening.

Do ocular migraine symptoms persist?

It’s possible that ocular migraine could persist even after recovery from COVID-19 in some people.

Some people develop headaches that last for months after COVID-19. For example, in one case study, a woman had persistent loss of smell and experienced headaches 80 days after the onset of her symptoms.

She experienced migraine-like headaches during her COVID-19 illness, but she reported that her subsequent headaches felt different.

Researchers are still trying to understand why some people develop long-haul COVID-19 symptoms after recovering from their initial infection. It’s possible that increased inflammation and neurological damage play a role.

The bottom line

Ocular migraine often refers to any headache that causes visual disturbances. It may also refer to a specific type of migraine that causes vision loss called retinal migraine.

Case studies report that some people with a history of migraine develop more frequent migraine episodes during COVID-19. Some people without a history of migraine also experience migraine-like headaches.

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