reshaping is a therapy to correct myopia by the
use of contact lenses. Also known as orthokeratology
and corneal refractive therapy, it has become a
common procedure in temporarily reducing or removing
Advancement in corneal reshaping contact lens
designs and materials had rendered it a more
convenient choice over surgery or refractive
correction for myopic cases. However, this therapy
requires proper education about its implementation
both for the practitioners and for patients to
ensure maximum benefit and safety.
The corneal reshaping process
Corneal reshaping, also known as corneal refractive
therapy or orthokeratology, was first implemented
in the early 1960s. The original goal of corneal
reshaping was to permanently change the shape
of the cornea by wearing specialized contact
lenses during sleep. Such contact lenses were
made of high oxygen permeable materials and more
advanced designs. The therapy involves central
epithelial thinning and midperipheral epithelial
and stromal thickening. Though it has broken
new grounds, there is still a lot more research
to be done in this field.
Effectiveness of corneal reshaping
There is still a lot of ground to be covered
in the effectiveness of corneal reshaping in
controlling myopia. When it started off, various
research labs reported short lived and erratic
results of corneal reshaping therapy. There were
any reports of significant achievements.
Three sets of tests conducted from the late-1970s
to the mid-1980s, implemented spherical design
(base curve steeper than secondary curve) contact
lenses worn for waking hours only. It was applied
on cases reporting a mean spherical equivalent
refractive divergence of about –2.50D.
The treatment time span ranged from 132 days
to 17.7 months. All three researches reported
a myopia reduction of less than 75% and recurrence
of the previous syndromes after the discontinuation
of the contact lens.
Hence, research in this field took a back seat
until the mid-1990s, when the possibility of
more advanced materials and designs brought hope.
The new contact lenses allowed nighttime use
and reported quicker and more noticeable results.
The latest studies have reported substantial
results within the first month. Rapid correction
of baseline refractive error has been reported
through the first 24 to 72 hours and expected
recovery over two weeks.
Advice from the prescribing eye care practitioner
Eye care practitioners should give users of
conreal reshaping contact lenses extensive advice
and information on their use. The advice can
and should include:
- To begin with, practitioners must inform
their patients that the refractive therapy
with corneal reshaping contact lenses ends
the moment the patient stops using the lenses.
They must also be cautioned that the lenses
have not proved effective in slowing the development
of myopia in children or adults.
- Practitioners should provide product labeling
information to their patients in brief and
compelling written directives highlighted by
simple graphic demonstrations.
- Patients should be given emergency contact
details of the practitioner.
- Practitioners should seek precise approval
and furnish detailed information to patients
before they take up corneal reshaping therapy.
This is done with a consent form and a pediatric
assent form for corneal reshaping contact lens
wear in chilren.
Side effects of corneal reshaping
There have been reports of various ill effects
of the use of corneal reshaping contact lenses.
They are as follows:
- Reversible asymptomatic corneal pigmentation
- Increase in higher order aberrations,
particularly spherical aberration
side effects like corneal ulcers or microbial
There have been alarming cases reported, especially
in children who have been using corneal reshaping
contact lenses for the control of myopia. Research
that compares the effect of the use of corneal
reshaping contact lens versus spectacles, report
corneal reshaping contact lenses slow the axial
growth of the eye 46% through a span of two years.
However, there have been some gaps in this research
and controversies remain about the frequency
and prevalence of microbial keratitis as a consequence
of corneal reshaping contact lens wear.
Safeguards against the side effects
For the user there are standard procedures to
follow to avoid side effects with corneal reshaping
- Do not rinse or store your contact lenses
in tap water.
- Clean and disinfect your contact
lenses every time you remove them from your
it should be done strictly according to the
guidelines issued by the manufacturer.
- Seek professional help if you suffer from
sudden and persistent redness, discomfort or
of vision while using the lenses.
- Visit your
practitioner every six months to check your
eyes and contact lenses, even if you have