Refractive Lens Surgery

Preface
The first recorded time a human lens was
removed for the purpose of addressing a
refractive error was by an ophthalmologist
named Fukala in 1890. We do not know
what type of criticism he experienced, but
we know that today he is a forgotten man in
ophthalmology. The introduction of this as
a concept in the late 1980s by both Drs. Paul
Koch and Robert Osher’s manuscripts, resulted
in considerable disdain and some
condemnation by some of their colleagues
and peers. At the time, refractive surgery in
the United States was limited to radial keratotomy.
With the development of excimer
lasers came a very marked change in the attitude
of eye surgeons internationally regarding
the concept of invading “healthy”
tissue for refractive purposes and within a
relatively short period of time, LASIK was a
firmly established procedure as were other
modalities of corneal refractive surgery.
However, we have come to recognize that
corneal refractive surgery, and especially
LASIK, has limitations. We have also
learned much in the recent past about
functional vision through the use of contrast
sensitivity and an analysis of higher
order optical aberrations. We have also
learned that the cornea has constant spherical
aberration but the lens has changing
spherical aberrations. In the young, the human
lens compensates for the cornea’s positive
spherical aberration, but as we age the
changing spherical aberration within the
lens exacerbates corneal spherical aberra-
tion. Because of the changing spherical
aberration in the lens, no matter what is
done to the cornea as a refractive surgery
modality, including the most sophisticated
custom corneal shaping, functional vision
is going to be degraded by changing spherical
aberration in the lens over time.
This coupled with the fact that higher
myopes and hyperopes, patients with early
cataracts, and presbyopes are not necessarily
good candidates for LASIK has resulted
in a fresh look at lens-based refractive surgery.
We have seen recent improvements in
phakic IOL technology and utilization and
we ourselves have been increasingly motivated
to work with lens related refractive
surgery modalities.
Our own work with power modulations,
the IOL Master, and wavefront technology
IOLs has convinced us that lens-related refractive
surgery can give superior results.
Stephen Klyce, MD, the developer of
corneal topography has demonstrated,
using topographical and wavefront analysis
methods, that IOL intraocular optics are
far superior to the optics of the most sophisticated,
customized wavefront treated
cornea. We have also seen the development
of new lens technologies including improved
multifocal IOLs, improved accommodative
IOLs, light adjustable IOLs, injectable
IOLs, and a variety of other
investigational IOL technologies that suggest
unimaginable possibilities. Our own
results with the Array and Crystalens have
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