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PRESBYOPIA
Presbyopia is the gradual decline in the ability to focus on close
objects or to see small print, as one gets older. It is universal
in occurrence in people over the age of 40, and is a normal and
almost inevitable part of the aging process.
There
are over 2 billion presbyopes worldwide with over 100 million
in the USA. Beginning at about age 40 one experiences blurred
vision at near, usually when reading, sewing or working at the
computer.
Conventional
Treatments
Conventional treatments to compensate for one’s “age
related” decrease in near vision include reading glasses
or bi-focals.
Monovision
Some can tolerate wearing one contact lens for distance and one
for near. This is called monovision. Monovision can also be created
through the LASIK and PRK procedures.
One
can also have monovision induced through a procedure called Conductive
Keratoplasty (CK). CK is a procedure in which the cornea or front
of the eye is steepened thermally making it nearsighted, thereby
able to see at near. A thermal probe is gently placed over several
spots gradually changing the eye’s shape
Blended
Vision
Vision is considered blended when part of the corrective lens
is used for distance and part is used for near. These lenses are
called “multifocal.” Multifocal lenses have rings of
different powers within. The human eye and brain seek out clear
images and discount the blurred areas. This effect can be induced
through contact lenses or with intraocular lenses.
Multifocal
contact lenses are worn like conventional contact lenses. Multifocal
intraocular lenses are placed within the eye, during a procedure
much like cataract removal. The human lens is removed and multifocal
intraocular lenses such as the ReZoom™ or Restor™ are
then inserted within the eye to blend near and distant vision.
Accommodating
Intraocular Lenses
Lenses are now available to place inside of the eye in order to
allow one to focus at near. These are called accommodating intraocular
lenses. This procedure involves removing one’s normal human
lens and replacing it with a lens that moves forward and backward
as the muscles inside the eye attempt to focus.
New
Technologies
New techniques are on the horizon to improve one’s near vision
without compromising distance vision. These include procedures
on the outside of the eye…the white part, which is called
the sclera. More advanced methods are being investigated that
include using lasers, and treatments in which tiny pieces of plastic
(approximately 1/3 the size of a grain of rice) are placed in
strategic positions, without entering the eye. The plastic implants
are situated around only one eye, yet both eyes improve in near
ability, without affecting distance vision. The doctors at Nevada
Eye and Ear are working closely in the development and clinical
trials of these new techniques as well as offering those that
are currently available.
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