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Custom LASIK or Wavefront LASIK
 Individualized Vision Correction
Custom LASIK surgery, also known as wavefront LASIK or wavefront-guided
LASIK, uses 3-dimensional measurements of how your eye processes
images to guide the laser in re-shaping the front part of the eye
(cornea).
With a wavefront measurement system, some extremely precise,
individualized vision correction outcomes may be achieved that would
be impossible with traditional LASIK surgery, contact lenses, or
eyeglasses.
You should be qualified under Food and Drug Administration
guidelines before custom wavefront LASIK would be considered for
your eye condition. Depending on the custom laser system used and
other factors such as appropriate thickness of your cornea, you
might be considered a candidate if you have mild to moderately high
degrees of common vision defects such as myopia, hyperopia, and
astigmatism.
With custom LASIK, your eye's ability to focus light rays is
measured, and a 3-D map is created that demonstrates irregularities
in the way your eye processes images. Information contained in the
map guides the laser in
customizing the treatment to reshape your eye's corneal surface so
that these irregularities can be corrected.
Standard prescriptions for glasses, contacts, or traditional LASIK
procedures can correct ordinary vision defects such as myopia,
hyperopia, and astigmatism. But other irregularities associated with
the eye's optical system could not be addressed until the advent of
wavefront and related technology used in custom LASIK.
Potential Benefits of
Wavefront-Guided Custom LASIK
Wavefront technology is groundbreaking because it has the
potential to improve not only how much you can see, visual acuity
measured by the standard 20/20 eye chart, but also how well you can
see, in terms of contrast sensitivity and fine detail. This
translates into a reduced risk of post-LASIK complications, such as
glare, halos, and difficulty with night vision.
How much you see depends on vision defects known as lower-order
aberrations associated with common refractive errors including
myopia, hyperopia, and astigmatism, which traditional LASIK can
treat.
How well you see can depend on presence of the type and numbers of
visual distortions known as higher-order aberrations, which can
include irregularities other than common refractive errors. These
higher-order aberrations can create problems such as decreased
contrast sensitivity or night vision, glare, shadows, and halos.
However, higher-order aberrations do not always affect vision.
Unlike traditional LASIK, custom LASIK treats both lower- and
higher-order aberrations.
Custom LASIK's
advantage lies in the area of quality of vision:
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Greater chance of achieving 20/20 vision
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Greater chance of achieving better than 20/20 vision
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Reduced chance of losing best-corrected vision
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Reduced chance of losing visual quality or contrast
sensitivity
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Reduced chance of night-vision disturbances and glare
A 2005 survey revealed that most refractive eye surgeons now use
wavefront-guided LASIK in their practices. Read more about the study
in the sidebar:
WAVEFRONT - GUIDED LASIK & CONTRAST
SENSITIVITY
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Refractive eye surgeons appear
overwhelmingly to favor customized or
wavefront LASIK as evidenced by results of a
2005 American Society of Cataract and
Refractive Surgery (ASCRS) survey of 4,645
U.S. members (16% responded). About 74% of
refractive surgeons now use wavefront-guided
LASIK in their practice, compared with fewer
than 10% in 2003.
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In certain cases, outcomes such as improved
night vision with use of wavefront-guided
LASIK appear to surpass results that can be
achieved with conventional LASIK.
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In August 2004, the U.S. Navy announced that
patients at its refractive surgery center
were achieving better distance vision and
night vision after custom LASIK than after
traditional LASIK.
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In a small study, 88 percent of contrast
sensitivity measurements improved after
wavefront-guided LASIK, while only 40
percent improved after regular LASIK. This
was one month after surgery.
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Uncorrected visual acuity of 20/20 or better
was achieved by similar numbers, however: 72
percent of the wavefront group and 70
percent of the regular LASIK group. The
study was published in the March 2004 issue
of Ophthalmology, the clinical
journal of the American Academy of
Ophthalmology.
FDA-Approved Custom LASIK Systems
Laser System
and Manufacturer |
FDA-Approved
Indications |
Features |
LADARVision 4000 with
CustomCornea
&
LADAR6000 with CustomCornea (Alcon) |
Myopia: up to -8 D with or without myopic astigmatism up
to -4 D
Hyperopia and hyperopic astigmatism: up to +5 D (near
vision problems) and astigmatism causing distance vision
problems up to -3 D |
Eye tracking,
integrated wavefront, small spot system for precise laser
application, no pupil dilation needed for treating larger
optical zones in LADAR6000 system |
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Technolas 217z Zyoptix
System
(Bausch & Lomb) |
Myopia: up to -7 D
with or without up to -3 D myopic astigmatism and total
refractive error equal to or less than 7.5 D |
Integrated wavefront
and "flying spot," meaning fast, uniform application of
laser beam with each pulse for smooth corneal surface |
|
Star S4 Active Trak with
CustomVue
(Visx) |
Myopia: up to -6
D, with or without up to -3 D myopic astigmatism
Hyperopia: up to +3 D with or without up to +2 D for
hyperopic astigmatism |
Eye tracking,
integrated wavefront, no pupil dilation required, which
speeds up procedure, unique wavefront analysis system known
as Fourier for increased resolution |
Star S4 IR with
CustomVue
(Visx) |
Myopia: up to -6 D
with or without up to -3 D of myopic astigmatism
Hyperopia: up to +3 D with or without up to +2 D of
hyperopic astigmatism
Mixed astigmatism: up to 5 D |
Same as S4 Active
Trak |
|
Allegretto Wave with
Allegro Analyzer
(WaveLight) |
Myopia: up to -7 D
with or without up to 3 D of astigmatism |
Scanning spot system,
eye tracking, integrated wavefront, algorithm (mathematical
measurement) based on population studies that helps minimize
possibility that a vision error known as spherical
aberration might be induced during vision correction |
| Note: D refers to
diopters. |
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