Topic Overview

What is nearsightedness?

Nearsightedness (myopia) is a common cause of blurred vision. It can be mild, moderate, or severe. If you are nearsighted, objects in the distance appear blurry and out of focus. You might squint or frown when trying to see distant objects clearly. View a photo as seen through a normal and a nearsighted eye.

Nearsightedness is usually a variation from normal, not a disease. Less often, nearsightedness happens because of another disease or condition.

What causes nearsightedness?

Most nearsightedness is caused by a natural change in the shape of the eyeball. Less often, nearsightedness may be caused by a change in the cornea or the lens.

These problems cause light rays entering the eye to focus in front of the retina. Normally, light focuses directly on the retina. See a picture of the parts of the eye.

There is nothing you can do to prevent nearsightedness.

What are the symptoms?

The main symptom is blurred vision when looking at distant objects. You may have trouble clearly seeing images or words on a blackboard, movie screen, or television. This can lead to poor school, athletic, or work performance.

Your child may be nearsighted if he or she squints or frowns, gets headaches often, or holds books or other objects very close to his or her face. Children who are nearsighted may sit at the front of the classroom or very close to the TV or movie screen. They may not be interested in sports or other activities that require good distance vision.

If you think that your child may be nearsighted, see an eye care specialist. Treating nearsightedness early may prevent children from having trouble in school and in social settings.

When does nearsightedness start? How does it change over time?

Nearsightedness usually begins in childhood between ages 6 and 12. During the teen years, as the eyeballs continue to grow, it may develop or get worse quickly. Teenagers may need new glasses every 12 months or even more often.

Nearsightedness usually stops getting worse by age 14 to 16 in women and by the mid-20s in men. Most nearsightedness stabilizes at a mild to moderate level.

How is nearsightedness diagnosed?

A routine eye exam can show whether you are nearsighted. The eye exam includes questions about your eyesight and a physical exam of your eyes. Ophthalmoscopy, tonometry, a slit lamp exam, and other vision tests are also part of a routine eye exam.