Intraocular
Lenses (IOLs)
The new multifocal and accommodating IOLs offer the possibility
of seeing well at more than one distance, without glasses or contacts.
Here are a few examples (note: this is not a complete list):
Crystalens .
This lens was designed to restore the eye's accommodation
ability, which is gradually reduced as presbyopia progresses.
In studies, about 80 percent of people who received the Crystalens
have near vision (equivalent to 20/20) after four months.
Presbyopia, is the break down of the ciliary muscle (which allows
focusing from near to far). The ciliary muscle contracts in its
effort to move the lens forward, bending it slightly for closeup
focusing; but the lens resists because it is not as flexible as
it was when the eye was younger.
AcrySof ReStor.
This lens uses apodized diffractive technology -- a design that
responds to how wide or small the eye's pupil might be -- to provide
near, intermediate and distance vision. Aspheric lenses, because
they are somewhat flat near the edges, are thought to improve
contrast sensitivity and provide better night vision than other
types of multifocal IOLs.
Clinical studies show 80 percent of people who received the lens
didn't use glasses for any activities after their cataract surgery.
Eighty-four percent who received the lens in both eyes had distance
vision of 20/25 or better, with near vision of 20/30 or better.
AcrySof
Toric Intraocular Lens. This lens is an advanced technology
that now makes it possible to correct the cataracts clouding your
vision -- and the corneal astigmatism distorting your vision --
at the same time.
The technology behind the AcrySof
Toric IOL offers precise astigmatic correction that reduces or
eliminates corneal astigmatism and delivers significantly improved
distance-vision without glasses or contacts for cataract patients
with pre-existing astigmatism.
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PRK (Photo Refractive Keratectomy)
PRK was the first procedure performed using the Excimer laser.
It corrects vision by reshaping the cornea. The difference between
LASIK and PRK is that with LASIK a corneal flap is created and
the laser is applied to the inner tissue of the cornea. With PRK,
the epithelium (or outer skin of the cornea) is removed and a
laser is applied to the surface of the cornea.
PRK can be used to correct low to high levels of nearsightedness,
farsightedness and astigmatism. PRK is preferred for patients
with thin corneas.
PRK vs. LASIK. Because PRK does not create a
permanent flap in the deeper corneal layers (the LASIK procedure
involves a mechanical microkeratome using a metal blade or a femtosecond
laser microkeratome to create a 'flap' out of the outer cornea),
the cornea's structural integrity is less altered by PRK.
The LASIK process covers the laser treated area with the flap
of tissue which is from 100 to 180 micrometres thick. This flap
can mute the nuances of the laser ablation, whereas PRK performs
the laser ablation at the outer surface of the cornea. The use
of the anti-metabolite mitomycin can minimize the risk of post-operative
haze in persons requiring larger PRK corrections.
PRK does not involve a knife, microkeratome, or cutting laser
as used in LASIK, but there may be more pain and slower visual
recovery.
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General Vision
Each year, many people experience a decrease in vision due to
progressive diseases or conditions of the eye. Often, there are
no symptoms indicating something is wrong, as with glaucoma. Therefore,
to insure the health of your eyes, a thorough examination by a
skilled eye doctor is essential to safeguard your sight.
When no diseases or conditions of the eye are present, persons
under forty should usually have an eye examination every two years.
Individuals over forty face an increased incidence of several
conditions that can jeopardize sight; therefore, an eye examination
every year is strongly recommended.
The Comprehensive, Dilated Eye Examination
A comprehensive examination that assesses the health and function
of your eyes is a wise investment toward protecting your eyesight.
Tests are conducted to assess your visual acuity (the sharpness
of your vision). The internal pressure of the eye is measured
to check for glaucoma. The internal and external structures of
the eye are observed to detect the presence of disease or other
abnormalities that may impair your vision or affect your health.
To allow the best view of the internal structures of the eye,
your eye will be dilated through the use of eye drops. These drops
cause the iris to open wide, giving the doctor a good view inside
your eye. While your eyes are dilated, close work or reading may
be difficult, plus bright sunlight may be annoying. The effects
of the dilating drops usually begin to subside after a few hours;
however, it is wise to bring good sunglasses to help you see in
bright sunlight following a dilated eye exam.
Recommendations are offered for protection and improvement in
your eyesight. Should you require corrective lenses, a procedure
known as a refraction is conducted to determine the prescription
that is best for you. Custom fitting of contact lenses plus instruction
on their care and use is also available from your eye doctor.
If you desire glasses, you may take the prescription to an optical
dispensary of your choice.
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Non-dilated Eye Exam
As a convenience for those individuals who must return to work
after the examination or cannot wait for the effects of the dilation
drops to abate, non-dilated eye examinations are available. If
there are indications for a thorough assessment of the interior
of the eye, the doctor will schedule a dilated examination at
a later date and time.
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