Common symptoms of ocular migraines are vision problems affecting one eye, headaches that continue for four to 72 hours, nausea, vomiting, and light or sound sensitivity, says WebMD. Vision problems include flashing lights, blind spots or complete blindness. Headaches usually affect one side, pulsate and get worse with activity.
The most telling symptom of an ocular migraine is vision problems that only affect one eye. A patient can try covering one eye then the other to determine if the symptoms are only occurring in one eye. Doctors are not sure what causes ocular migraines, but some point to blood vessel spasms in the retina or changes in the nerve cells of the retina as possible causes. Patients suffering from ocular migraines often have a higher risk of becoming permanently blind in one eye, reports WebMD.
The doctor rules out other conditions that have similar symptoms before diagnosing a patient with ocular migraines. Amaurosis fugax is a condition that leads to temporary blindness due to a blockage in the blood flow in the eye. Other possible conditions are spasms in the artery in the retina or giant cell arteritis, which causes swelling of the blood vessels. Autoimmune diseases, drug abuse and conditions that lead to irregular blood clotting may also cause similar symptoms, according to WebMD.
Symptoms of an ocular migraine may present themselves 20 to 30 minutes before the onset of a headache and the intensity of the headache will range from mild to severe, often lasting for several hours.
Although the cause for these migraines remains a mystery, many doctors believe the flashes of light and other symptoms are caused by a cortical spreading depression. This phenomenon causes a negative effect in the electrical impulses in the brain.