Generally speaking, it is possible for migraines to cause dilated eyes. Migraine is a chronic disorder characterized with a moderate to severe headache due to the constriction and expansion of blood vessels in the brain. There are plenty of nerves and vessels in our brain, which is very complicated combination. In addition, the dilated eyes is related to nervous system. Once nervous system is sitmulated, it is easy to get pupil eyes. Some study on migraine said the dilated eyes is caused by postganglionic sympathetic nerve spasms during migraine. However, the dilated eyes is just a temporary symptom, which can disappear shortly after if you treat it correctly and timely. Thus, go to the hospital to receive a professional treatment, meanwhile, keep a healthy diet. Once the migraines disappear, the dilated eyes will go away at the same time.