
ReSTOR®


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The latest technological advance in lens-based surgery
is the introduction of the apodized diffractive intraocular
lens implant called the ReSTOR®.
This multifocal implant, when used with cataract surgery,
can greatly reduce or even eliminate the need for glasses,
for both distance and reading! The topic of intraocular
lenses (IOL) is a complex one, so let’s spend
a little time going over the concepts.
Routine cataract surgery with a traditional type of
implant (not the ReSTOR® implant) will not completely
eliminate the need for glasses. While distance vision
can be made clear, reading vision is compromised (again,
when a traditional intraocular lens implant
is used).
In patients under approximately 40 years of age, the
natural crystalline lens retains the ability to flex
in a process called accommodation. This allows an individual
to generate the extra focusing power needed to read
up close. After 40, the ability to accommodate diminishes
more quickly, which results in a person needing bifocals
or reading glasses. While most cataract-age patients
have already lost this accommodation, the need for reading
glasses can be “accelerated” by removal
of the natural crystalline lens; for all purposes, the
traditional intraocular lens implant cannot
accommodate.
TRADITIONAL MONOFOCAL IMPLANT
The traditional monofocal intraocular lens implant
only focuses at one point, either distance or near,
or somewhere in between (intermediate), but almost
never at two or all three points simultaneously. Hence,
the term monofocal or “one focus”.
With monofocal implants, one of three strategies can
chosen, if both eyes are having surgery:
a) Implant selection so that both eyes focused at distance. While
glasses may still be necessary for distance, they will almost certainly be
necessary for reading and intermediate vision.
b) Implant selection so that both eyes focused at near. While glasses
may still be required for reading or intermediate vision, glasses almost certainly
required for distance.
c) Implant selection so that one eye focused at distance, and the other
eye for reading.
Glasses may still be required for both distance and
near, but choosing this option can reduce overall dependence
on glasses. This is called monovision. Monovision
can work well but it is a compromise. Decreased
depth perception and difficulty with vision under dim
lighting conditions (such as night driving) may occur. Golfers
and pilots may not like this. People who drive
at night extensively may not like monovision.
MULTIFOCAL IMPLANT: THE ReSTOR® IMPLANT
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ReSTOR® implant |
The multifocal implant is quite different from the
traditional monofocal implant. One such multifocal
implant is the ReSTOR® intraocular lens
implant.
(There are other brands of multifocal implants.) It
is a highly sophisticated implant that produces
two simultaneous focal points, for distance and near,
almost like the lens of bifocal glasses. A patient
unconsciously learns to switch between the two focal
points, depending on what is being viewed. The benefit
of using this implant is that each
eye can see both
distance and near. This
is quite different than the monovision option (see
previous paragraph) using the more traditional monofocal
lens implant, where only one eye is focused at distance,
and the other eye is focused at near. Vision
with the ReSTOR® is arguably a more natural way
of seeing. In a study of the ReSTOR® implant for
cataract patients (this study may not apply
to patients undergoing refractive lensectomy), 92
out of 100 ReSTOR® patients reported never
needing glasses for distance, and 81/100 not needing
glasses for reading. The ReSTOR® implant
is designed for clear reading vision at 14 inches.
Reading material may need to be held closer than usual
for some patients. Intermediate or computer vision,
without glasses, is acceptable for a large number of
ReSTOR® patients (82/100 in above cited study). ReSTOR® patients
may have to move closer to the computer screen or intermediate
range targets, to see very clearly without glasses.
Intermediate vision appears to improve over time.
The best visual results are obtained when both eyes
receive the ReSTOR® implant. It is
not recommended that only one eye receive the ReSTOR® implant. This
is an implant
designed to be used in both eyes.
The optimal
result with the ReSTOR® implant requires
getting as close to a “zero” distance prescription
as possible. A few patients who have refractive
lensectomy using the ReSTOR® implant, will
require a "touch-up" procedure to realize
the full potential of this lens implant. In other
words, to fine-tune the visual results, sometimes an
additional procedure may need to be done afterward. The
additional procedure may involve correction of astigmatism
with either a limbal relaxing incisions (LRI) or astigmatic
keratotomy (AK), both of which can be done in the office. Another
procedure which is sometimes used to refine the ReSTOR® results
is laser vision correction, like LASIK, which is done
at another facility.
Are you a candidate for the ReSTOR® implant? Only
your ophthalmologist can tell you. After a complete
eye exam and additional testing, your doctor will be
able to determine if you are a suitable candidate for
ReSTOR®. Your doctor will talk to you about
the risks of surgery, and those specific to multifocal
implants. For patients who meet the criteria, the
ReSTOR® implant can be a life-changing experience.
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