Headache can be caused due to eye problems which is basically refractive errors or squint.It can happen both in adults and in children.Headaches due to refractive errors or squint usually start later during the day.So when you wake up with headache in the morning it is not due to eyes.Eyes are well rested and they are relaxed a lot when you are asleep. Refractive errors are more commonly astigmatism or long sight. Usually myopia does not cause headaches.Because when a person is myopic that means he can see up close pretty easily.He doesn't have to focus unless he has to see distance.Other refractive errors can cause mild to severe headaches sometimes even to the extent of resembling a migraine headache. It is very important that adults who are experiencing headaches should have their eyes examined.They may have a refractive error which when corrected will take care of their headache and eye strain problems. This occurs more in the adults over 30 years of age.Because after 30 years the eye muscles slowly start losing their focusing ability.Depending on the nature of the work this can occur as early as 30 years of age may be even closer to the forties.Please make sure to get your eyes examined before going for a CT scan for headache..