Nearsightedness, or myopia, as it is medically termed, is a vision condition in which close objects are seen clearly, but objects farther away appear blurred. Nearsightedness occurs when the eyeball is too long or the cornea, the clear cover of the eye, has too much curvature. As a result, the light entering the eye isn't focused correctly and distance objects look blurred.
Generally, nearsightedness first occurs in school-age children. Because the eye continues to grow during childhood, it typically progresses until about age 20. However, nearsightedness may also develop in adults due to visual stress or health conditions such as diabetes. Approximately 30 percent of the U.S. population is affected by myopia.
A comprehensive eye examination by a doctor of optometry will include testing for myopia. Glasses or contact lenses can be prescribed to correct nearsightedness by bending the visual image that enters the eye, focusing the image correctly onto the retina.