Cornea
Transplants: Restoring sight
with donated eyes
A healthy cornea — the
transparent, dome-shaped surface
of your eye — is an essential
component of sharp, clear
vision. It accounts for a large
part of your eye's focusing
power. Any condition that
distorts your cornea or
diminishes its transparency can
harm your vision — sometimes
severely. One treatment option
may be a cornea transplant (also
known as keratoplasty).
Cornea transplants are one of
the most common organ and tissue
transplants performed in the
world. Find out who might
benefit from a cornea transplant
and what's involved in the
procedure.
Who is a cornea transplant
for?
A number of conditions can be
treated with a cornea
transplant, including:
- Thinning of the cornea
- Cornea scarring, caused
by infection or injury
- Clouding of the cornea
- Swelling of the cornea
- Corneal ulcers,
including those caused by
infection
Most cornea transplants are
used to restore vision. If
something disrupts the structure
of your cornea — making it very
thin or uneven, for example —
you might receive a cornea
transplant. If you have had a
painful corneal infection
resulting in significant
discomfort, a cornea transplant
may be recommended for pain
relief.
Cornea transplants are
occasionally performed for
cosmetic reasons, as well. Some
conditions that affect the
cornea may mar the appearance of
the eye. Corneal scarring, for
instance, can appear grey or
white. Because of technological
advances, such as the
development of colored contact
lenses, cosmetic transplants are
less common today than they were
in the past.
Whether you'll rely on
glasses or have perfect vision
after a cornea transplant will
depend on several factors,
including your disease or
condition.
How do you prepare for a
cornea transplant?
Make arrangements to have
someone accompany you home after
surgery, since you may be
groggy. Tell your doctor about
any medications you're taking —
prescription or over-the-counter
— and ask if you should stop
taking some or all of them
before the surgery. Finally,
follow your doctor's
instructions on drinking or
eating before the procedure.
How is a cornea transplant
done?
In a cornea transplant, a
surgeon replaces a portion of
your cornea with a different one
from a donor. Donor corneas
(grafts) become available when
families donate the eyes of a
deceased loved one. Just about
anyone can donate corneas and,
unlike other organ and tissue
donations, there usually isn't a
long waiting list for people who
need cornea transplants.
Before surgery you'll receive
a sedative, which means you
aren't asleep during the
procedure. Some people drift off
during surgery and don't
remember the procedure
afterward, while others stay
aware of their surroundings and
can communicate with the
surgical team. Either way, you
won't feel any pain because your
eye is completely numbed with a
local anesthetic. Though you
won't be able to see the surgery
being performed on your eye, you
may notice when the surgeon
moves instruments in and out of
the light in front of your eye.
In the most common type of
cornea transplant — called
penetrating keratoplasty — your
surgeon cuts through your entire
cornea to remove a small
button-sized disc. An instrument
that acts like a cookie cutter,
called a trephine, makes this
precise circular cut. The donor
cornea, cut to fit, is placed in
the opening. Your surgeon then
uses a fine thread to stitch the
new cornea into place. The
stitches are removed at a later
visit to your eye doctor. The
entire surgery takes about an
hour, depending on your
individual condition.
You'll receive a protective
shield to wear over your eye.
Wearing the shield will make
your eye more comfortable as you
recover and will protect your
eye from accidentally being
bumped.
With some types of cornea
problems, a full-thickness
transplant isn't always the best
treatment. Partial-thickness
(lamellar) transplants may be
used in certain situations.
-
Deep lamellar
transplant. This
transplant replaces only the
innermost of your cornea's
five layers. A small
incision is made in the side
of your eyeball to allow for
removal of your cornea's
inner layer without injuring
the outer layers. A donor
graft replaces the removed
portion. This procedure is
helpful in faster recovery
with less sutures and is
increasingly being performed
by corneal surgeons. Cornea
Services at retina
Foundation were the first in
the state to perform this
procedure also called as
DSEK ( Descemet's Stripping
Endothelial Keratoplasty)
-
Surface lamellar
transplant.
Although it's very uncommon,
eye damage may only involve
the outer layers of the
cornea. These layers, too,
can be removed and replaced
with a donor graft. This
procedure is referrred to as
Deep Anterior Lamellar
Keratoplasty and is very
useful in patients with
Advanced Keratoconus
What can you expect during
recovery?
After surgery you'll be taken
to a recovery room to rest for
an hour or so until you're ready
to go home. It's important to
wear the protective shield over
your eye until your doctor says
you can safely remove it —
generally within three days of
surgery.
You'll receive eyedrops to
control swelling and guard
against infection. If your eye
feels dry, talk to your doctor
about using artificial tears.
Never rub or put direct pressure
on your eye.
You'll meet with your eye
doctor the next day to check the
status of your eye and to look
for postoperative problems.
Expect to visit your eye doctor
every week or two for the first
month after surgery and then
every two weeks for about three
months. It takes about a year
for your eye to heal completely.
Until your eye heals, take
precautions to keep your eye
safe from injury. For at least
the first month after surgery:
-
Shield your eye.
Wear glasses or a patch
during the day. Wear your
protective shield at night.
-
Keep water out of
your eye. Wear your
protective shield when you
shower or wash your hair.
-
Avoid dust and sand.
These particles can irritate
your healing eye.
-
Reduce pressure on
your eye. Take a
break from activities such
as exercising, dancing or
jogging to avoid putting
excess pressure on your eye.
Avoid lifting heavy objects.
Move slowly and carefully
since your vision may be altered
temporarily as your eye heals.
When you can return to work
depends on what your job
involves. Office workers may be
comfortable going back to work
in a week. Wait six to eight
weeks before returning to a
manual labor job.
What are the risks of cornea
transplant?
Cornea transplants are
relatively safe and have been
performed for many years. But,
like any surgery, cornea
transplants carry the risk of
complications. Common signs and
symptoms that might represent
complications include:
- Decreased vision
- Increased reddening of
your eye
- Pain
- Sensitivity to light
- Light flashes or
floaters
If any of these symptoms
develop and persist for more
than six hours, call your eye
doctor immediately. Prompt
treatment is essential. Without
treatment, complications can
lead to the need to replace your
transplanted cornea.
Though rare, serious
complications can occur,
including:
- Infection
- Wound problems, such as
a broken stitch, which can
be uncomfortable and impede
healing
- Imperfections on the
outermost layer of the
cornea, which can cause haze
or scarring
- Bleeding
- Swelling in the front of
the eye, including
inflammation of the iris (iritis)
- Glaucoma — abnormally
high pressure inside your
eyeball, which can lead to
optic nerve damage and
vision loss
Follow your ophthalmologist's
directions about your
medications and follow-up
appointments. Careful adherence
to these directions will help
prevent complications and allow
for early treatment of any
problems that might arise.
About one in five people
undergoing cornea transplant
eventually reject the donor
cornea, making it necessary to
transplant another one.
Rejection most often occurs
within the first year after the
transplant. Your ophthalmologist
may recognize the early signs of
rejection and be able to modify
your therapy to prevent
rejection.
