An ocular migraine is a type of migraine headache that is associated with visual disturbances in one eye. This type of migraine is not common, and is often diagnosed after other possible causes for the symptoms are ruled out.
Ocular migraines are often treated with the same drugs that are used to prevent and treat the more common types of migraine. Read on to learn how to recognize when you are suffering from an ocular migraine, and what remedies are available to you.
Treatment Options for Ocular Migraines
Ocular migraine is not well understood, and some treatments are supportive in nature, meant only to help deal with symptoms.
Certain medications can also be helpful in preventing an episode. Triptans, which are sometimes used to treat other types of migraines, are not typically used to treat ocular migraines. Some of the medications that may be used to treat ocular migraine include:
- Aspirin: This drug, which is a type of salicylate that can be bought over-the-counter, may be used to reduce inflammation and pain during an ocular migraine. Low doses of aspirin may also be used as a preventative therapy, though this is still experimental.
- Anti-spasmotics: Divalproex sodium (Depakote) or topiramate (Topamax) are drugs that are often used to treat epilepsy. These drugs may also be used in the prevention of migraines.
- Calcium-channel blockers: Several types of these drugs, such as verapamil (Verelan) and nifedipine (Procardia), may work to prevent migraines by stopping the constriction of blood vessels. They are not typically a first choice for preventing migraines, although they may be used as a second-line therapy.
- Tricyclic antidepressants: Some tricyclic antidepressants such as amitriptyline (Elavil) or nortriptyline (Pamelor) are prescribed to prevent migraines. It’s unclear how they work to prevent migraines, but it’s thought that they affect the action of serotonin on the brain.
- Beta-blockers: Beta blockers such as propranolol (Inderal) act on the blood vessels, causing them to relax and open up. This class of drugs is typically used to treat high blood pressure and cardiac conditions, but can also be effective in the treatment of migraines. It’s not clear how these drugs may prevent migraines.
What is an Ocular Migraine?
An ocular migraine, also called a retinal migraine, is a less common type of migraine that is characterized by visual symptoms such as flashes or blind spots. Migraines in general are not well understood, and ocular migraines in particular have not been studied extensively.
Ocular migraines are more common in young women, and may occur more commonly in those who have a history of migraine headaches with aurae (an aura could be a feeling like a breeze, or a vision such as a bright light, that occurs prior to a headache).
Diagnosis of this type of migraine is often considered a diagnosis of exclusion, because other conditions that cause similar symptoms must be ruled out.
Symptoms of an Ocular Migraine
The International Headache Society (IHS) has defined the symptoms that are typical of a retinal or ocular migraine. These symptoms are monocular (that is, they occur in only one eye), temporary, and include:
- Scintillations: seeing something that looks like flash of light, lightning, or a sparkle. Halos or lines may also be seen.
- Scotoma: a temporary blind spot, black spot, blurriness, or a partial loss of vision.
- Blindness: partial or complete blindness in one eye.
- Migraine headache: The symptoms in the eye are accompanied by a headache that can last from a few hours to a few days. The headache is often located on the same side of the head as the eye that is experiencing symptoms.
- Other: Symptoms that typically occur with a migraine may also occur, such as light sensitivity, nausea, and vomiting.
Other types of migraines can cause visual problems, especially flashes of light and blind spots in the field of vision. The important distinction is that with an ocular migraine, these symptoms only occur in one eye.
It can be difficult to determine which eye is experiencing the symptoms, or if they are taking place in both eyes. A qualified healthcare professional can help determine the location of the symptoms while they are occurring.
If the symptoms can’t be assessed at that time, a patient may try covering one eye. With one eye covered, it may be easier to tell which eye is affected, or if the problem is occurring in both eyes.
These symptoms usually last for only a few minutes, but they can go on for as long as an hour in some cases.
Any sudden vision problems (black or blind spots, blurriness, or flashes) should be reported to a physician immediately, whether they occur with or without a headache. Vision problems can be a symptom of a medical emergency.
What Causes Ocular Migraines?
It’s not known exactly what causes an ocular migraine. It’s thought to be related to the constriction of blood vessels, possibly the blood vessels in the retina.
Diagnosis of an Ocular Migraine
The diagnosis of an ocular migraine is often made by comparing the patient’s symptoms to the criteria established by the IHS. Migraines can be difficult to diagnose; other conditions that could be causing the symptoms need to be ruled out.
The potential difficulties of making a diagnosis is the reason the IHS (and other groups) have established criteria to help clinicians to make a proper diagnosis.
The diagnostic criteria for the diagnosis of an ocular migraine from the IHS Classification ICHD-II are:
- Two attacks in which the patient experiences the symptoms outlined in B and C.
- The patient sees flashing lights (scintillations), a blind spot (scotoma), or experiences blindness in one eye. A healthcare professional must be able to confirm these symptoms with an examination or a detailed drawing/description.
- The patient experiences a headache, meeting criteria for a “migraine without aura.” The headache may begin at the same time as the visual symptoms, but must begin within an hour after the symptoms start.
- An eye exam performed when there are no ocular or migraine symptoms turns up no evidence of any disease.
- There is no other explanation, such as another disease or disorder, for the symptoms.
There are several other conditions that should be ruled out when symptoms of an ocular migraine are present. These other conditions may have similar symptoms, but will require different treatments.
Unfortunately, there is a long list of other causes of ocular symptoms that should be ruled out, including:
- Embolism: A blockage in the blood flow that can occur in the retina, the brain, or several other parts of the body. An embolism in the brain can cause headache, stroke, and problems with vision.
- Increased intracranial pressure: Abnormally high pressure around the brain can cause headache double vision, or “buzzing” in the ears.
- Orbital apex mass: A mass or a tumor in the eye is rare, but can cause symptoms similar to a ocular migraine.
- Giant cell arteritis: Also called temporal arteritis or cranial arteritis, this condition involves inflammation of the arteries in the temple and may cause vision loss, headaches, or other symptoms such as fevers, weight loss, neck or jaw pain, and scalp tenderness
- Increased viscosity: When blood becomes more viscous (thicker) than it should be, headache and visual problems can result.
- Hemianopia: This condition is defined by the loss of the loss of half of the visual field in both eyes, and may occur after a brain injury or a stroke.
- Ischemic Optic neuropathy: A sudden change in vision could be caused by an abnormality in the optic nerve. This condition is not common, and is typically found in patients who have diabetes, high blood pressure, or high cholesterol
- Carotid dissection: A tear in one of the two carotid arteries located on either side of the neck is often associated with stroke. This condition is a medical emergency, and treatment may be necessary to prevent a stroke. Symptoms may also include different sized pupils and a droopy eyelid.
Complications Of Ocular Migraine
Any problems in vision should immediately be reported to a physician. The symptoms of ocular migraine should be investigated fully in order to determine that there is no other disease or condition present.
People who experience ocular migraines may be at risk for permanent vision loss. Patients should follow up with their physician on a regular basis and discuss any changes in their symptoms or their headaches.