Astigmatism is a common eye condition that's easily corrected with eyeglasses, contact lenses, or elective surgery. Astigmatism occurs in nearly everybody to some degree. A person's eye is naturally round in shape. Under normal circumstances, when light enters the eye, it bends evenly, creating a clear view of the object. However, the cornea of a person with astigmatism is shaped more like a football or the back of a spoon. For this person, when light enters the eye, it is bent more in one direction than the other, allowing only part of the object to be in focus at one time. Objects at any distance can appear blurry.
Astigmatism can be hereditary or often present at birth.
Your optometrist can diagnose astigmatism with a thorough eye exam. Astigmatism may occur with other refractive errors such as myopia (nearsightedness) and hyperopia (farsightedness). Unfortunately, astigmatism often goes undetected in school-age children.
Almost all degrees of astigmatism can be corrected with properly prescribed eyeglasses or contact lenses. For a person with only a slight degree of astigmatism, corrective lenses may not be needed at all, as long as other conditions such as nearsightedness or farsightedness are not present. If the astigmatism is moderate to high, however, corrective lenses are probably needed.
For astigmatism, special corrective lenses called toric lenses are prescribed. Toric lenses have greater light bending power in one direction than the other. After performing various tests, your optometrist will determine the ideal toric lens prescription for your astigmatism.