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Johns Hopkins Symptoms and Remedies

Johns Hopkins Medicine

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Presbyopia

As the lens loses its flexibility with age, it becomes difficult for the ciliary muscles to shape it to the thickness required for near vision.

What is it?

Presbyopia is the inability to focus on close objects, which occurs as the lens of the eye progressively loses its flexibility—a normal consequence of aging. The lens, located just behind the pupil, expands and contracts in response to the tiny ciliary muscle surrounding it, providing clear focus over a range of distances. When the ciliary muscle is relaxed, tension in the area around the lens holds the lens at a thickness adequate for distance vision.When the ciliary contracts, this tension decreases, which allows the lens to expand (thicken) and focus on a close object. With age, the lens hardens and becomes less flexible and the ciliary muscle may weaken; these changes make it increasingly difficult to focus at close range. Sometime after age 40, most people notice that close objects seem more blurry, and that newspapers and books must be held at arm's length for print to be seen clearly. Prescription reading glasses compensate for this loss of focusing power. Those who already require glasses to correct other vision problems, such as nearsightedness or astigmatism, may need bi- or trifocal lenses when presbyopia develops. Presbyopia is not a serious health risk and does not lead to blindness.

What Causes It?

  • Aging causes the lens in the eye to harden and become less flexible. The ciliary muscle may lose some of its ability to contract as well.

Prevention

  • Presbyopia cannot be prevented.
  • Contrary to popular belief, vision cannot be improved by refusing to wear prescription lenses if you need them or by performing so-called visionstrengthening exercises.

Diagnosis

  • An ophthalmologist or optometrist will perform an eye examination.

How to Treat It

  • Eyeglasses are prescribed to allow nearby objects to be seen clearly. Some people may need bifocals, trifocals, or multiple pairs of glasses if additional vision problems exist; others may only need reading glasses.
  • Bifocal contact lenses are available.
  • Monovision—one eye corrected to allow clear distance vision, the other eye corrected for clear near vision—may be employed using contact lenses, intraocular implants, or refractive surgery.
  • The prescription for eyeglasses may need to be updated approximately every two years as lens flexibility is progressively lost. After age 65, the eye's lens becomes completely inflexible, so the prescription for corrective lenses usually stabilizes.

When to Call a Doctor

  • Make an appointment with an eye professional if it becomes difficult to see nearby objects clearly.