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Wavefront and Higher-Order
Aberrations
Previously, with
conventional methods of eye
examinations, only
lower-order vision errors
could be diagnosed and
treated. Higher-order
aberrations such as coma,
trefoil, and spherical
aberration were largely
ignored by eye care
professionals because their
impact on vision was
believed at the time to be
slight and because no
feasible means existed to
precisely identify or
correct them.
Now that higher-order
aberrations can be
accurately defined by
wavefront technology and
corrected by new kinds of
spectacles, contact lenses,
intraocular lenses, and
refractive surgery (adaptive
optics), they have become
more important factors in
eye examinations.
In the past, these
higher-order aberrations
received even more attention
because they were identified
as sometimes serious side
effects of refractive
surgery, showing up as
halos, ghosts, and a host of
other debilitating vision
symptoms. Newer
wavefront-guided lasers used
in vision correction
surgery, however, now have
been shown to have the
ability to reduce certain
higher-order aberrations,
which potentially can
improve low light image
quality during activities
such as driving at night.
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