Astigmatism is a common vision problem caused by an irregular shape of the cornea or lens of the eye. Instead of being perfectly round, the cornea may be curved more in one direction than the other. This irregular curvature prevents light from focusing properly on the retina, leading to blurred or distorted vision.<br /><br />When a person with astigmatism tries to focus on objects for a long time, the eyes must work harder to adjust. This extra effort of the eye muscles often causes eye strain, which can lead to headaches. The headaches are usually felt in the forehead or around the eyes, especially after reading, working on a computer, or doing close-up tasks.<br /><br />Correcting astigmatism with glasses, contact lenses, or refractive surgery can reduce eye strain and prevent headaches. Regular eye exams are important for early diagnosis and proper treatment.