The treatment itself will last about 10 minutes per
eye, so if you have a favourite CD, bring it along and
we can play it in the treatment room
You are awake during the procedure but your eye is
numbed with anaesthetic drops to minimise discomfort.
You lie flat on a treatment bed beneath the laser.
An antiseptic solution is used to flush clean the surface
of the eye and lashes. Plastic drapes cover and sweep
the lashes away from the eye. The eye is held open
with a lid speculum.
The first part of the procedure involves lifting the epithelium.
This is the thin, continually renewing, protective layer
on the surface of the cornea. This layer needs to be
moved aside to allow the laser to be applied to the underlying
true substance of the cornea (called Bowman’s layer).
A ring shaped device is seated onto the white of the eye.
This locks onto the eye with suction. This is associated
with a mild sensation of pressure and the vision will
fade out. The epithelial separator is then coupled to
the ring and slowly passes across the cornea from the
side, moving towards the nose. A fine vibration may be
sensed as it does so. This instrument flattens the cornea
and a high precision blunt edge lifts the central epithelium
from the substance of the cornea. The epithelium remains
attached medially and this acts as a hinge. The separator
is then moved back to its start position and the entire
device is removed from the eye. Vision returns.
The epithelial “flap” is then lifted and stroked
onto the nose side of the eye (remaining attached at its
hinge) to expose the underlying cornea. The eye is positioned
under the laser and the patient fixes their vision upon
a flashing red light. The machine has a tracking device
which locks onto the pupil and keeps the laser centred
on the eye. The laser then removes some tissue from the
superficial layers of the corneal stroma (including Bowman’s
layer). A computer determines precisely how much tissue
is to be removed. The laser delivers pulses of ultra violet
light onto the surface of the cornea. Each pulse removes
a microscopic part of the cornea. The cornea is reshaped
so that light rays are focused more directly onto the retina
and images are in better focus. Finally the epithelial “flap” is
replaced. A bandage soft contact lens is then placed onto
the eye.
After the surgery antibiotic and steroid drops are
applied to the eye and a protective shield and/or pad
is placed over the eyelids and you will be able to
go into the recovery room.
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