248 West 116th Street
New York, NY 10026

Astigmatism and Presbyopia

What Is Astigmatism?
Astigmatism is a common eye condition that's easily corrected by eyeglasses, contact lenses, or elective surgery.

Astigmatism is characterized by an irregular curvature of the cornea. This is one type of refractive error. Astigmatism occurs in nearly everybody to some degree. For significant curvature, correction is required.

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.

What Causes Astigmatism?
Astigmatism can be hereditary or often present at birth.

How is Astigmatism Diagnosed?
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.

How Are Astigmatisms Corrected?
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.

• Contact Lenses.
  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 eye doctor will determine the ideal toric lens prescription for your astigmatism.

Presbyopia

The gradual loss of your eyes' ability to focus actively on nearby objects — is a not-so-subtle reminder that you've reached middle age. A natural, often annoying part of aging, presbyopia usually becomes noticeable in your early to mid-40s and continues to worsen until around age 65.

You may become aware of presbyopia when you start holding books and newspapers at arm's length to be able to read them. If you're nearsighted, you might temporarily manage presbyopia by reading without your glasses.

A basic eye exam can confirm presbyopia. You can correct the condition with prescription eyeglasses.