A retinal migraine, or ocular migraine, is a rare form of migraine. This type of migraine includes repeated bouts of short–lasting, diminished vision or blindness in one eye. These bouts of diminished vision or blindness may precede or accompany a headache and nausea.
The symptoms of a retinal migraine are the same as a regular migraine, but they include a temporary change in vision of one eye.
People experiencing retinal migraines will often lose vision in one eye only. This is usually brief, lasting about 10 to 20 minutes. In some cases, this can last up to an hour. Some people will also see a pattern of black spots called “scotomas.” These black spots gradually get bigger and cause complete loss of vision.
Partial Vision Loss
Other people will partially lose vision in one eye. This is usually characterized by blurry, dim vision or twinkling lights called “scintillations.” This can last up to 60 minutes.
Sometimes, people who experience retinal migraines will experience a headache after or during the attack on their vision. These headaches can last for a few hours to a few days. Physical sickness, nausea, and painful throbbing of the head often accompany the headaches. These typically affect one side of the head. This pain may feel worse when you’re physically active.
Retinal migraines occur when the blood vessels to the eyes start to constrict, or narrow. This reduces the blood flow to one of your eyes. After the migraine is over, your blood vessels relax and open up. This allows blood flow to resume, and vision is then restored.
Some eye experts believe that retinal migraines result from changes in nerve cells spreading across the retina. Typically, long-term damage to the eye is rare. Retinal migraines usually aren’t a sign of serious problems within the eye. There’s a small chance that the reduced blood flow can damage the retina. If this happens, it can lead to long-term vision impairment.
The following activities and conditions can trigger retinal migraines:
- intense exercise
- tobacco use
- low blood sugar
- birth control pills that modify hormonal levels
- being in higher altitudes
- hot temperatures
- caffeine withdrawal
Additionally, certain foods and liquids can trigger retinal migraines, including:
- foods that contain nitrates, such as sausage, hot dogs, and other processed meats
- foods with tyramine, such as smoked fish, cured meats, and certain soy products
- products that contain monosodium glutamate, including snack chips, broths, soups, and seasonings
- alcoholic beverages including certain beers and red wine
- beverages and foods with caffeine
Retinal migraines are triggered by different things in different people.
Both children and adults of any age can experience retinal migraines. These do tend to be more common in the following groups:
- people under 40 years old
- people with a family history of retinal migraines or headaches
- people with a personal history of migraines or headaches
People with certain illnesses that impact the blood vessels and eyes may also be at risk. These illnesses include:
- sickle cell disease
- hardening of the arteries
- giant cell arteritis, or inflammation of blood vessels in the scalp
There aren’t any specific tests to diagnose a retinal migraine. If you see a doctor or optometrist during a retinal migraine attack, they may use a tool called an “ophthalmoscope” to see if there’s a decreased blood flow to your eye. This generally isn’t feasible because attacks are usually brief.
Doctors typically diagnose a retinal migraine by investigating the symptoms, conducting a general examination, and reviewing a personal and family medical history. Retinal migraines are usually diagnosed by a process of exclusion, meaning that symptoms such as transient blindness can’t be explained by other serious eye diseases or conditions.
If retinal migraines aren’t experienced frequently, doctors or optometrists may prescribe medications typically used to treat other forms of migraines. These include ergotamines, nonsteroidal anti-inflammatory drugs such as aspirin and ibuprofen, and antinausea medications.
Additionally, doctors may look at your individual triggers and try to deal with them actively to prevent future episodes.
An eye specialist may sometimes prescribe specific medications for a retinal migraine including a beta-blocker such as propranolol, an antidepressant such as Amitriptyline, or an anticonvulsant such as Valproate. More research needs to be done in this area to come up with a more definitive treatment.
Retinal migraines typically begin with total or partial vision loss, or visual impairment such as twinkling lights. This typically lasts no more than an hour. The headache phase starts during or after the visual symptoms appear. This headache can last a few hours to several days.
Typically, these migraines occur once every few months. Episodes can occur more or less frequently than this. Either way, you should consult with an eye specialist if you’ve experienced the associated vision impairment.