Presbyopia is a condition in which the lens of the eye loses its ability to focus, making it difficult to see objects up close.
Causes, incidence, and risk factors
The lens of the eye needs to change its length or shape to focus on smaller objects, or objects that get closer or farther away. This is called the elasticity of the lens. This elasticity is slowly lost as people age. The result is a slow decrease in the ability of the eye to focus on nearby objects.
People usually notice the condition at around age 45, when they realize that they need to hold reading materials further away in order to focus on them. Presbyopia is a natural part of the aging process and it affects everyone.