Topic Overview
What is presbyopia?
Presbyopia is the normal worsening of vision with age,
especially near vision. As you approach middle age, the lenses in your eyes
begin to thicken and lose their flexibility. The ability of the lens to bend
allows our eyes to focus on objects at varying distances (accommodation);
the loss of this ability means that vision declines and objects cannot be
brought into focus. This generally becomes noticeable some time around age 45
when you realize that you have to hold a book or newspaper farther from your
face to focus on it.
Normally, a muscle surrounding the
lens
in your eye expands or contracts, depending on
the distance to the object being focused on. With presbyopia, the muscle still
works, but the lens has lost much of its flexibility and won't bend enough to
bring close objects into focus. Images are then
focused
behind the
retina instead of directly on it, leaving close vision
blurred. Putting greater distance between the object and your eye brings the
object into focus—for example, holding a newspaper farther from your face. For
this reason, presbyopia is sometimes called "long-arm syndrome."
What causes presbyopia?
Presbyopia is a natural part of aging. As you grow older, the
lenses in your eyes thicken and lose their elasticity, and the muscles
surrounding the lenses weaken. Both these changes decrease your ability to
focus, especially on near objects. The changes take place gradually, though it
may seem that this loss of accommodation occurs quickly.
What are the symptoms?
The main symptom of presbyopia is blurred vision, especially
while doing close work or attempting to focus on near objects. This is worse in
dim light or when you are fatigued. Presbyopia can also cause headaches or eye
strain.
How is presbyopia diagnosed?
Presbyopia can usually be diagnosed with a general eye
examination. Your health professional will usually test your visual acuity
(sharpness of vision), your refractive power (the ability of your eyes to
change focus from near to far), the condition of the muscles in your eye, and
the condition of your
retina
. He or she will probably also take measurements
for glasses or contact lenses at the time of the examination.
How is it treated?
Presbyopia can usually be corrected with glasses or contact
lenses. If you didn't need glasses or contacts before presbyopia appeared, you
can probably correct your eyesight by using reading glasses for close work.
Glasses you buy without a prescription may be sufficient, but check with your
eye doctor to determine the right glasses for you. If you do buy glasses
without a prescription, try out a few different pairs of varying strength
(magnification) to make sure you get glasses that will allow you to read
without straining.
If you already use glasses or contacts to correct
nearsightedness,
farsightedness, or
astigmatism, you'll need a new prescription that will
also correct presbyopia. You may wish to use bifocals, in which distant vision
is corrected at eye level and close vision is corrected at the bottom. Other
options include trifocal glasses, which can correct for distant, near, and
middle vision; bifocal contact lenses; or monovision contact lenses, which
correct distant vision in your dominant eye and close vision in your weaker
eye. Your prescription may have to be adjusted over time as presbyopia worsens.
If you don't want to wear glasses or contacts, surgery may be an
option to correct presbyopia. Procedures being used to treat presbyopia include
laser-assisted in situ keratomileusis (LASIK) and photorefractive keratectomy
(PRK), which use lasers to reshape the
cornea
of your eye, or a clear lens extraction with an
intraocular lens implant, in which the natural lens is removed and an
artificial one is implanted to replace it.
None of these surgeries will restore perfect vision—you will have
to compromise. For example, you may have surgery to correct distance vision and
then use reading glasses for near vision, or you may have one eye adjusted for
near vision and one for distance vision, which would lessen your depth
perception. New procedures that reverse presbyopia are being developed and
tested.
Will my vision continue to worsen?
Near vision begins to decline due to presbyopia around age 45.
Your eyes continue to lose the ability to accommodate—requiring changes to
prescriptions for glasses or contacts—until you reach your early 60s. At this
point, accommodation stabilizes and your vision should stop getting
worse.