Condition Basics 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 (Figure 1) . You might squint or frown when trying to see distant objects clearly.
Nearsightedness is usually a variation from normal, not a disease. Less often, nearsightedness happens because of another disease or condition.
What causes it? 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 (Figure 2) .
These problems cause light rays entering the eye to focus in front of the retina (Figure 3) . Normally, light focuses directly on the retina
What happens when you are nearsighted? 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 20. Most nearsightedness stabilizes at a mild to moderate level.
How is it 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, slit lamp exams, and other tests that check vision and eye health are also part of a routine eye exam.
Eye exams should be done for new babies and at all routine checkups.
How is nearsightedness treated? Most people who are nearsighted use eyeglasses or contact lenses to correct their vision.
Surgery can also reduce or fix nearsightedness. There are several surgery options, such as LASIK, PRK (photorefractive keratectomy), and artificial lens implants. The goal of surgery is to help you see more clearly without glasses or contacts. Most doctors consider 20/40 vision
If glasses or contact lenses are inconvenient for your work or lifestyle, surgery may be a good choice. But nearsightedness is not a disease, and a nearsighted eye is otherwise normal and healthy. Weigh your desire to have clear vision without glasses or contacts against the risks and cost of surgery. And be aware that you may still need to wear glasses or contact lenses after surgery.
If your vision doesn't bother you and if you have no driving problems or other safety concerns, you don't need to have any treatment. Nearsightedness won't affect the health of your eye, and it won't get worse just because you don't wear glasses or don't have surgery.
If you are nearsighted, get regular eye exams, and see your eye care specialist if you have changes in your vision.
Figure 1 - View Through Normal and Nearsighted Eye Source: National Eye Institute, U.S. National Institutes of Health. Available online: http://www.nei.nih.gov
If you are nearsighted, objects in the distance appear blurry and out of focus.
Current as of: July 31, 2024
Author: Ignite Healthwise, LLC StaffClinical Review Board
Figure 2 - Cornea, Lens, and Iris The iris is the coloured part of the eye. A circular muscle in the iris controls the amount of light entering the eye through the pupil, the black area in the centre of the iris.
The cornea is the outer clear, round structure that covers the iris and the pupil. The cornea directs light rays into the eye and helps focus them on the light-sensitive retina at the back of the eye, providing sharp, clear vision.
The lens is located behind the iris and is normally clear. Light passes through the pupil to the lens. Small muscles attached to the lens can make the lens change shape, allowing the eyes to focus on near or far objects.
Current as of: September 27, 2023
Author: Ignite Healthwise, LLC StaffClinical Review Board
Figure 3 - Nearsightedness (Myopia) If you are nearsighted, objects in the distance appear blurry and out of focus.
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. The change in shape causes light rays that enter the eye to focus in front of the retina rather than directly on it, which leads to blurred vision.
Current as of: July 31, 2024
Author: Ignite Healthwise, LLC StaffClinical Review Board
