Ocular Migraines 101
When you can see a migraine headache
Visual disturbances with migraine headaches are common. Auras preceding or occurring at the same time as migraine headaches can include visual symptoms that include flashes of light, blind or shimmering spots, or zigzag patterns in your field of vision. However, some people experience these visual disturbances without the pain of a migraine headache. The correct medical terminology for these is “ophthalmic" migraines, but they're also called eye, visual, or ocular migraines.
Ocular migraines are part of a group of migraine variants that include signs and symptoms that occur without the pain of a migraine headache. Migraine variants are less common than typical migraine headaches, typically occurring in children and young adults.
Ocular migraine symptoms include:
- scotoma , a small blind spot that gradually increases in size
- scintillations, flickering or flashing lights, and
- metamorphopsia ¸ shimmering zigzag lines.
These effects can occur individually or in combination. Typically, the vision in only one eye is affected, and the visual disturbances of ocular migraines are consistent from one episode to the next. Flashing or colored lights, a blind spot, or jagged lines start in one part of the field of vision and move across it before disappearing altogether. Eye or visual migraines can last just a few minutes or up to an hour.
Ocular migraines result from the same processes inside the brain that cause migraine headaches with pain. Despite the fact that symptoms are experienced in the visual field, the structures of the eye remain unchanged. Blood flow to the area of the brain that controls vision alters as blood vessels constrict and then dilate. While the precise reason for the changes in blood vessel size is still undetermined, the location where these changes take place in ocular migraines is clear. The visual cortex is at the very back of your skull, above the point where it begins to taper into the back of your neck.
Diagnosing ocular migraine is usually done on the basis of a history of multiple episodes with complete recovery within an hour or two and no symptoms in between episodes. A family history of migraines helps confirm the diagnosis. When visual symptoms don't promptly resolve or are accompanied by other symptoms, such as numbness, confusion, or weakness of the muscles controlling eye movements, further investigation is warranted. This is also the case if total blindness in one eye occurs, with or without headache pain. Necessary tests might include a CT or MRI of the brain or an ophthalmologic evaluation.
The best way to avoid ocular migraines is to avoid known triggers. These might include strong lights, certain foods, stress, overexertion, and sleep deprivation. When an ocular migraine strikes, the best response is to rest until the symptoms pass. If you also experience nausea and vomiting, your doctor can prescribe medications to help. Avoid driving or other activities in which your safety depends on excellent vision.
If you experience repeated ocular migraines, speak with your doctor about the possibility of using medications to prevent migraines from occurring. Several types of medications, including beta blockers and antidepressants, have been widely used to help people stay migraine-free. With or without pain, there's no reason to suffer needlessly.