The lens of an eye is normally clear. If the lens becomes cloudy (opacified) it is called a cataract.
Review Date 8/8/2019
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.