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Presbyopia is an age-associated progressive loss of the focusing power of the lens. This results in difficulty seeing objects close-up.

Causes, incidence, and risk factors

The focusing power of the eye, which depends upon the inherent elasticity of the lens, is gradually lost as people age. This results in a slow decrease in the ability of the eye to focus on objects nearby.

People usually notice the condition 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 affects everyone.


  • Decreased focusing ability for near objects
  • Eyestrain
  • Headache

Signs and tests

A general eye examination will be performed, including measurements to determine a prescription for glasses or contact lenses.

Tests may include:

  • Visual acuity
  • Refraction test
  • Muscle integrity
  • Slit-lamp
  • Retinal examination


Presbyopia can be corrected with glasses or contact lenses. In some cases, the addition of bifocals to an existing lens prescription is sufficient. As the ability to focus up close worsens, the prescription needs to be changed accordingly.

Around the age of 65, the eyes have usually lost most of the elasticity needed to focus up close. However, it will still be possible to read with the help of the appropriate prescription. Even so, you may find it necessary to hold reading materials further away, and you may require larger print and more light to read by.

People who do not need glasses for distance vision may only need half glasses or reading glasses.

With the use of contact lenses, some people choose to correct one eye for near and one eye for far. This is called "monovision" and eliminates the need for bifocals or reading glasses, but can interfere with depth perception.

New surgical procedures can also provide solutions for those who do not want to wear glasses or contacts.

Expectations (prognosis)

Vision can be corrected with glasses or contact lenses.


If uncorrected, progressive vision difficulty can cause problems with driving, lifestyle, or work.

Calling your health care provider

Call your health care provider or ophthalmologist if eye strain or decreased ability to focus on close objects occurs.


There is no proven prevention for presbyopia.

Update Date: 4/25/2002

Raymond S. Douglas, M.D., Ph.D., Department of Ophthalmology, Universtiy of Pennsylvania Medical Center, Philadelphia, PA. Review provided by VeriMed Healthcare Network.

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Last updated: Tue, 06 Jan 2009 00:20:03 GMT