Presbyopia is a condition in which the lens of the eye loses its elasticity and its ability to focus. In the normal eye, the lens changes shape so that light rays from a near object are focused clearly on the retina. In presbyopia, the lens hardens and can't change shape, so the light rays are focused behind the retina. The image that lands on the retina is blurry and out of focus.
Review Date 10/16/2020
Updated by: Franklin W. Lusby, MD, ophthalmologist, Lusby Vision Institute, La Jolla, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.