and can often increase the Percentage
of Time Strabismic (POTS) among
those with eye turns. In cases of
strabismus and amblyopia, specialty
prescribing is often the best first step,
and should be given great attention,”
he said.
He noted the use of aniseikonic/
isophoric lens designs, now made
relatively simple through ShawLens.
com, can be an easy first step in
addressing the causes.
With this type of lens, the images are
equalized at the retinal level. Sensory
fusion can now occur. The patient
can integrate the two images more
easily. We’ve found through clinical
research that the time was taken to
correct the amblyopia is significantly
reduced and, best of all, vision
suppression using a patch or drops
may not be necessary.
“Amblyopia, commonly referred to as
lazy eye, is weakness of vision in an
otherwise healthy eye. It is frequently
associated with a blurred image from
an uncorrected refractive error in one
eye or mis-alignment of the images
due to strabismus,” said Peter J Shaw
OD, CEO Shaw Lens and Adjunct
Associate Research Professor,
University of Waterloo.
He said in either case the result is
that the visual cortex of the brain is
unable to fuse the images together as
one. In order to deal with the image
difference and resultant disruption
the brain actively inhibits and ignores
the less viable image from one eye
and over time this behavior, if left
untreated, permanently impairs the
resultant vision. Research has shown
that this inhibition actually occurs in
the brain and not the eye, so really,
perhaps it should be called lazy brain.
“The most frequent causes of
amblyopia is blurred vision due to
anisometropia or anisometropic astigmatism,” he said. “These are common
vision conditions that even when
corrected with eyeglasses fail to fully
remediate the problem. This can
create an obstacle to fusion in visual
cortex in the form of aniseikonia
(unequally sized ocular images due
to spectacle image magnification
inequality).”
He said in order to increase the success
in the treatment of amblyopia many
optometrist specializing in developmental vision employ the use of iseikonic
corrective therapies including
contact lenses, refractive procedures
and iseikonic eyeglass lenses. Iseikonic
therapies including iseikonic eyeglass
lenses ensure that the images in the
brain are equally sized and provide the
necessary foundation to fully remediate
the amblyopic vision.
“When all barriers to eye teaming
are eliminated, the vision system can
function as nature intended.
The results from iseikonic therapies
can be dramatic with improvement in
vision from mild to moderate straight
eye, refractive amblyopia seeming to
occur instantly,” he said. “Sometimes
vision therapy is required to achieve
the fullest vision potential, new
techniques in therapy often include
3D games and eye-hand coordination
tasks,” he said adding experts in vision
agree that patching is no longer considered a primary therapy for amblyopia.
“Teaching the eyes to work together
provides a lasting and less invasive
approach to successfully treating amblyopia. Iseikonic lenses such as Shaw
Lens provide the foundation to enable
eye teaming,” he said.
Optical Prism | March 2016 19