What are bifocal contact lenses?
Bifocal contact lenses are lenses that provide correction
for both near vision and far vision. There are several
basic types of bifocal contact lenses:
- Lenses with the distance prescription in the center of
the lens and the reading prescription all around it. In
some cases the reading prescription is on the inside and
the distance prescription is on the outside.
- Lenses with the distance prescription on the top and the
reading prescription on the bottom (like bifocal
glasses). These lenses are usually weighted at the
bottom so the reading prescription stays on the bottom
when they are being worn.
- Lenses with magnifying power becoming progressively
greater from the outside to the center of the lens
(called aspheric bifocal lenses).
When are bifocal contact lenses prescribed?
Bifocal contact lenses may be helpful for people who have
trouble seeing things close up (for example, reading small
print) and do not want to wear reading glasses or bifocal
glasses.
Usually bifocal contact lenses are prescribed for both eyes.
Sometimes a bifocal contact lens may be prescribed for only
one eye, and a regular lens or no lens at all for the other
eye.
How do I choose the right type?
You may need to try several different types of lenses.
Bifocal contacts come as soft lenses and gas permeable
("hard") lenses. Your doctor can recommend which type you
should try, and trial lenses can be ordered.
The selection of type of bifocal contact lens is based on
factors such as:
- your age and eyeglass prescription
- the type of work you do
- the way you usually use your eyes (for example, if you
look straight ahead to read rather than looking down)
- the lighting conditions where you usually read
- the shape of your eye
- the size of your pupils.
What happens during the adjustment period?
You may adjust quickly to bifocal contacts, but many people
have some problems with their new lenses. You may feel that
your vision is not as clear as you are used to, or it may
change when the lens moves on your eye. You may see images
that seem to jump when you change from distance to close-up
vision, a three-dimensional effect or ghost image when you
read, or a halo around lights. Problems like these can
sometimes be corrected with a change in lenses. Or the
problems may lessen as you get used to the new lenses.
Will bifocal contact lenses work for me?
Bifocal contacts work for many people, but they are not for
everyone. There have been many improvements in bifocal
contact lenses since they were first used. Work with your
eye doctor to find the type that is best for you, and try it
for as long as your doctor recommends. Discuss your trial
experiences with your doctor, and then decide whether
bifocal contacts are the right choice for your vision needs.
When should I call my doctor?
All types of contact lenses can increase the risk of eye
infections if they are not cared for properly. Be sure to
talk to your eye doctor about how to clean your lenses, how
often you should clean them, and how long you can safely
wear your lenses at a time. Never use tap water to clean or
store your lenses. If you start having redness or
irritation in an eye that does not get better when you take
out your lens, you should call your doctor right away.
This content is reviewed periodically and is subject to
change as new health information becomes available. The
information is intended to inform and educate and is not a
replacement for medical evaluation, advice, diagnosis or
treatment by a healthcare professional.
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