HOW IS KC TREATED?
In the earliest stages of KC, ordinary eyeglasses
may correct the mild myopia (near-sightedness) and
astigmatism that is experienced. As the disease advances,
gas-permeable contact lenses are the only way to
correct vision adequately, and most of
the time this is a permanent remedy. These must be fitted with great care and
most KC patients need frequent checkups and frequent contact lens changes to
achieve good vision and comfort. In some instances the use of one lens on top
of another (so-called
piggy-backing) provides an alternative solution. It should be noted that technological
advances in both gas-permeable and soft lenses are being realized constantly,
offering more and more possibilities for keratoconus patients. For example,
a gas-permeable scleral lens was developed in 1994 and has proven to be helpful
in even advanced KC. This is why contact-lens wearing is the preferred method
of managing KC until surgery is necessary.
In only about 10% of KC cases a corneal transplant
becomes necessary. In this process much of the central
cornea of the KC patient is removed and is replaced
with the cornea of a recently deceased person. Eye
banks in major cities collect healthy corneas from
decedents and fulfill requests from eye surgeons
for these corneas. This is a highly organized and
sophisticated system and corneal transplants are
quite common operations and very successful. The
probability of rejection is less than that of any
other transplanted organ simply because the cornea
has no blood supply. Rejection of other organs is
usually due to incompatibility between the donor
and the recipient and is mediated by blood cells.
While there is a 95% rate of success in corneal
transplants for KC, this procedure, as with all operations,
involves potentially serious risks. In cases where
the first transplant is not successful, a second
can be undertaken successfully. Recurrence of KC
in the transplanted cornea has happened but is extremely
rare. Permanent loss of vision, though also extremely
rare, can occur. Corneal transplantation is considered
only in those cases in which contact lenses cannot
be worn or provide inadequate vision despite the
most skilled efforts.
"Corneal transplants are
95% successful"
While the surgical transplantation
of a new cornea will resolve the basic problem of
corneal surface irregularity, eyeglasses / contact
lenses are usually needed for vision correction.
In many cases RGP contact lenses will be required
to correct the large amount of corneal distortion
that is sometimes associated with the transplant
regardless of the skill of the surgeon.
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