Hello, It may occur in Ocular migraine. Loss of eyesight may be due to reduction in blood flow to the eye causing damage to the retina and blood vessels. As a result, vision loss is a potential complication of a retinal migraine. Sometimes, visual disturbances may be experienced before migraine affects both eyes. It is migraine with aura. In Ophthalmic migraine some people get the visual symptoms without the headache due to a temporary spasm in the blood vessels behind the eye. You are suggested to get clinically examined by an eye specialist, get required investigations done. Let diagnosis get confirmed so that treatment can be started at the earliest. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K., General & Family Physician