Presbyopia

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

In the young eye, the lens needs to change its length or shape to focus on objects that are close. The ability of the lens to change shape 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.

SYMPTOMS

• Decreased focusing ability for near objects
• Eyestrain
• Headache

EXAMS AND TESTS

The health care provider will perform a general eye examination, including measurements to determine a prescription for glasses or contact lenses.

Tests may include:

• Examination of the retina
• Muscle integrity test
• Refraction test
• Slit-lamp test
• Visual acuity

TREATMENT

There is no cure for presbyopia, but it can be corrected with glasses or contact lenses. In some cases, adding bifocals to an existing lens prescription is enough. As the ability to focus up close worsens, the bifocal prescription needs to be strengthened.

Around age 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 right prescription. Even so, you may find that you need to hold reading materials farther away, and you may need larger print and more light by which to read.

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

People who are nearsighted may be able to take off their distance glasses to read.

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

Sometimes monovision can be produced through laser vision correction. There are also bifocal contact lenses that can correct for both near and far vision in both eyes.

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

OUTLOOK (PROGNOSIS)

Vision can be corrected with glasses or contact lenses.

POSSIBLE COMPLICATIONS

If it is not corrected, vision difficulty that gets worse over time can cause problems with driving, lifestyle, or work.

WHEN TO CONTACT A MEDICAL PROFESSIONAL

Call your health care provider or ophthalmologist if you have eye strain or are less able to focus on close objects.

PREVENTION

There is no proven prevention for presbyopia.

Source: http://www.nlm.nih.gov/medlineplus/ency/article/001026.htm