Wavefront-LASIK
This latest procedure, which is still in the developmental stage, uses
an optical diagnostic device called an aberrometer – which utilizes
the wavefront technology frequently mentioned in the press - to determine
the objective and the quantitative optical impairment of the human eye.
This procedure aims to correct the combined refractive error resulting
from the optical system of the eye as a whole: the cornea, the lens and
the vitreous body.
Light enters the eye as flat sheets (wavefronts) and, under ideal optical
circumstances, exit the eye as wavefronts as well. An Aberrometer measures
the exiting wavefronts as they are projected onto a CCD camera and are
analyzed by a computer.
From the deviations in intensity of the light and from its enlargement,
reduction and distortion effects, the aberrometer not only determines
spherical and cylindrical refractive errors but also determines the so-called
"higher order aberrations", which have an effect on the quality
of optical imaging. These deviations are then translated into an ablation
profile for the laser.
This procedure is only possible with laser systems that have a variable
laser beam profile which can be freely applied. Additionally, this procedure
requires an active eye tracking system as well as the iris tracker, which
compensates for rotation errors.
The inventors believe - and first results seem to show - that in certain
cases, sharper vision can be achieved with wavefront technology. This
technology is particularly interesting for patients who do not perfect
vision although neither the cornea nor the optical nerve show any pathological
changes and should therefore be fully functioning.
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