Where is the cornea
Repairing the cornea: let there be sight
how do we keep our vision clear and what
happens if that view starts to cloud
over our window onto the world is the
cornea which lets light into our eyes to
keep the cornea in perfect condition a
fine layer of cells on its surface are
constantly replaced flowing in from a
region called the limbus outside the
limbus a thick layer of cells called the
conjunctiva protects the rest of our eye
the limbus acts as a barrier between the
cornea and the conjunctiva but if it
gets damaged the conjunctiva can start
to grow across the cornea clouding the
window and cutting out the light
eyedrops or vitamin A supplements can
help speed up healing from minor damage
but if the damage is more severe more
drastic action might be necessary
doctors can take some of the patients
healthy limbus and transplant it but
take too much and they risk causing the
same problem at the donor site instead
they can transplant cells or even entire
corneas from other people corneal
transplants are well understood
procedures and they bring the whole
package
Lamia linda's in all but the risk of the
body rejecting the transplant is high
and the drugs needed to make the process
work have dangerous side effects if the
patient has a small amount of healthy
limbers left doctors can still just take
a chunk and amplify the cells in the lab
before transplanting them back into the
eye that way there's no rejection and
far fewer cells are needed sounds good
but it requires specialist equipment and
the patient still might not have enough
healthy limbus left to work with
in these cases scientists can repair the
damage using cells where a patient's
mouth that these aren't totally
transparent and so cloud the cornea
better than nothing
but far from ideal in the most severe
cases doctors can insert a prosthetic
cornea but they try to avoid this as it
brings with it a risk of infection and
of a dangerous buildup of pressure
behind the prosthesis
no one knows which of these treatments
is most successful as no one studied it
instead treatment plans often just based
on each doctors preference or the
facilities at the Medical Center in the
future researchers would like to grow
bespoke corneas by engineering the
patient's own stem cells these would be
complete like a transplant but they
wouldn't be rejected they'd be a perfect
fit for the patient's eye and doctors
wouldn't need to use any limbal cells to
build them however research into these
sorts of treatments is still in the very
early stages and for now it remains way
out of sight
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