A migraine is a common neurological condition occurring in at least 15-20% of the population and in up to 50% of women.
Classic migraine usually starts with visual symptoms (often zig-zag lines, colored lights or flashes of light expanding to one side of your vision over 10-30 minutes), followed by a single-sided pounding severe headache. The headache is usually associated with nausea, vomiting, and light sensitivity. Sometimes visual symptoms and even neurologic dysfunction may occur without the headache. This is called "migraine variant".
Common migraine may cause only a headache felt on both sides of the head. This form of migraine may be responsible for the headaches that many people may have attributed to tension, stress, or sinus pain.
What causes migraine?
While it is not clear exactly how a migraine works, it is believed that the basic cause of migraine is an abnormality in the neurotransimitter serotonin, an important chemical used by your brain cells. During a migraine attack, changes in serotonin affect blood vessels in your brain, often causing the vessels to constrict. These changes in blood flow decrease the oxygen supply to the brain. If this oxygen supply is decreased long enough, a stroke is possible. Fortunately, this is rare. Certain foods may trigger a migraine attack, including aged cheese, nitrates (often found in cured meats, hot dogs and other processed foods), chocolate, red wine, monosodium glutamate (usually called MSG, a flavor enhancer frequently found in some food), caffeine, aspartame (the artificial sweetener found in Nutrasweet), and alcohol.
Hormonal changes are frequently associated with migraine-especially pregnancy, use of birth control pills, and menstrual periods or menopause.
Patients often attribute their migraine to stress. While stress probably does not cause migraine, it may affect the frequency of attacks. Interestingly, however, most migraine attacks seem to occur following stress relief, often at the beginning of a weekend or vacation.
People who experience migraine often have a family history of headaches or a prior history of motion sickness.
What are symptoms of migraine?
The most common sign of migraine is headache lasting for hours or days. Symptoms generally include:
- Pounding pain on one side of your head (or steady pain on both sides of your head);
- Sensitivity to light and sound;
- Nausea, vomiting;
- Visual symptoms (usually in both eyes but often to one side) with some of the following characteristics:
- A spot of blurring that expands to one side over 10-30 minutes;
- An expanding border often described as zig-zag lines, "shimmering" or resembling "heat waves" or "sparklers";
- Vision loss in one eye only, involving the entire field or only the upper or lower section.
Rare symptoms include double vision, change in lid position (lid droop), or change in pupil size (both smaller and larger).
In very rare cases, the visual problems associated with migraine may not entirely resolve. This may be due to a stroke associated with migraine.
How is migraine treated?
Treatment usually first involves avoiding factors known to precipitate a migraine attack, such as foods, environmental triggers such as perfume, and medications such as birth control pills. Over-the-counter anti-inflammatory medications (such as aspirin, ibuprofen, etc.) may reduce the severity of an acute attack. Drugs that constrict the blood vessels, including caffeine and ergotamines, are sometimes used. Also, certain prescription medications that deal directly with the presumed chemical imbalances of migraine are available (including Imitrex, Amerge, Maxalt, and Zomig).
If migraine attacks are severe or frequent enough, medication may be required on a regular basis (prophylactic medication groups are tricyclics, beta-blockers, calcium channel blockers, and some anti-seizure medications.
Your ophthalmologist may refer you to a neurologist or another specialist for further test and evaluation.
Copyright © 2003 American Academy of Ophthalmology, The Eye M.D. Association
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