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LASIK, a surgical procedure
which uses a laser to reshape the cornea, is currently
the most common form of refractive surgery (surgery
to reduce or eliminate the need for glasses).
Over the last ten-plus years, LASIK has proven
to be a very effective and relatively safe alternative
to glasses and contact lenses for many patients.
However, patients with extremely high prescriptions,
extremely thin corneas, or unusually shaped corneas
often present challenges with LASIK. Some patients
are better candidates for other types of procedures.
Surgical options which do not involve reshaping
the cornea are now available in the US, and are
allowing patients previously untreatable with
LASIK to experience the benefits of refractive
surgery. One such option is a category of procedures
known as "Phakic IOLs.”
“Phakic” refers to an eye which has
its natural lens in place (“aphakic”
is an eye which has had its natural lens removed).
IOL stands for “Intra-Ocular Lens”—these
are small artificial lens implants which have
been used for over half a century in various forms,
usually in conjunction with cataract surgery (surgery
to remove a cloudy natural lens from the eye).
The term “Phakic IOL” means an artificial
lens which is implanted inside the eye, leaving
the eye’s natural lens in place. This procedure
can be thought of as placing glasses or contact
lenses inside the eye, to stay there indefinitely.
There are different styles of phakic IOLs, made
of various materials, and there are several potential
implantation sites within the eye. Some are implanted
in front of the iris (the colored part of the
eye), and some behind the iris.
The implantation of a phakic IOL is done as an
outpatient in an ambulatory surgery center, under
local or topical (eyedrop) anesthesia. A small
incision (a few millimeters) is made to allow
the insertion of the implant. Most patients experience
little to no discomfort during the actual procedure,
which may take thirty to sixty minutes. Remarkably,
many patients report an instantaneous, dramatic
improvement in their vision, similar to LASIK.
Click
here to read information provided by the FDA
about Phakic Intraocular Lenses.
 Click
here download our Phakic IOL - an alternative
to LASIK brochure.
The first phakic IOL to receive full FDA approval
is the Verisyse™ lens. It was approved in
October 2004, for the reduction or elimination
of nearsightedness ranging from –5.00D to
–20.00D. This is well beyond the range of
LASIK, which is approved to treat up to –14.00D
(however, many doctors do not go this high with
LASIK even though it is approved), and custom
LASIK, which is approved to treat up to –8.00D.
The Verisyse™ lens is made of polymethylmethacrylate
(PMMA, a type of plastic), and is placed in front
of the iris, the colored part of the eye. The
lens attaches to the iris and is therefore known
as an iris-fixated lens.
This lens design has been used in Europe for nearly
two decades. In that time, more than 150,000 phakic
refractive procedures have been performed using
the Verisyse™ design. The implant has shown
excellent stability of vision over time, and a
very high degree of predictability.
The Verisyse™
IOL |
In the FDA clinical studies, in 204 eyes with
one year of followup, 47% of eyes saw 20/20 or
better uncorrected, and 93.6% saw 20/40 or better
uncorrected. These are remarkably good results
given the extremely high level of nearsightedness
being treated (mean preoperative myopia was –12.6D).
At three years postop, 92% had uncorrected vision
of 20/40 or better, and 61.7% were seeing 20/25
or better uncorrected1.
91% of patients rated their satisfaction with
surgery “favorable,” and 92% would recommend
the procedure to a friend or relative2.
In a recent study published in the scientific
journal Ophthalmology, for treatments between
–9.00D and –19.50D, 72.2% of patients
who received Verisyse™ in one eye and LASIK
in the other preferred the Verisyse™ eye
because of the better quality of vision3.
The Visian ICL is a phakic intraocular lens which
is placed behind the iris, in front of the natural
lens in the eye. The Visian lens is capable of
correcting from –3.00D to –20.00D of
nearsightedness. It is made of collamer, a co-polymer
that contains a small amount of purified collagen.
It is very biocompatible (doesn't cause a reaction
inside the eye) and stable. It also contains an
ultraviolet light filter. The soft, flexible nature
of the Visian ICL allows it to be injected into
the eye through a very small incision. Typically,
the small incision is self-sealing and no stitches
are needed.
The Visian ICL |
The FDA clinical trials
for nearsightedness concluded in 1999, and worldwide,
over 40,000 ICLs have been implanted to date.
In the FDA clinical studies, 526 eyes were implanted
with the ICL, with an average preop nearsightedness
of -10.06D. At three years postop, 59% of eyes
had 20/20 or better uncorrected vision, and nearly
95% had 20/40 or better uncorrected4.
A recent study comparing the ICL to LASIK for
correction between -8.00D and -12.00D showed a
higher percentage of patients ending up with 20/20
or better uncorrected with the ICL (52%) than
with LASIK (36%), at one year post-op5.
1 Continued
follow-up reinforces efficacy, safety of myopic
phakic IOL. Ophthalmology Times, October 23,
2004.
2 FDA Clinical Trials, Data on
file, Ophtec USA, Inc.
3 El Danasoury MA, Maghraby AE,
Gamali TO. Comparison of Iris-fixed Artisan
Lens Implantation with Excimer Laser In Situ
Keratomileusis in Correcting Myopia between
–9.00 and –19.50 Diopters. Ophthalmology,
2002; 109:955-64.
4 FDA Clinical Trials, Data in
file, Staar Surgical, Inc.
5 DR Sanders MD PHD, JA Vuchick
MD. Comparison of Implantable Contact Lens
and Laser Assisted In Situ Keratomileusis
for Moderate to High Myopia. Cornea, 22 (4):
324-331, 2003. |
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