Laser Eye Surgery Explained
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The front surface of the eye
(cornea) acts as a lens. With perfect sight, the image is brought
into sharp focus on the back surface of the eye (retina). Vision
problems occur when the image is not accurately focused on the back
of the eye and vision is blurred.
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The usual method for correcting
eyesight problems and disorders is with glasses or contact lenses.
Their power is measured in dioptres, according to the strength of a
round (spherical) lens that enables the clearest possible
vision.
Laser Correction for Short Sight (Myopia)
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Short sight is hereditary and
develops through the teens, affecting 20% of the population. If you
are short-sighted, the focusing power of your eyes is too strong.
Objects at a distance appear blurred and close up vision is
clear.
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Your glasses will make things
look smaller when held at arms length (a negative power lens is
thinner in the middle). The laser is set to reduce the thickness of
the cornea in the central zone, reducing its focusing power. Images
are then brought into correct focus. Laser eye correction treatment
for Myopia is very simple and effective. Example of a short
sight prescription:
|
Eye |
Sphere
|
CYL
|
AXIS
|
|
Right
Eye
|
-2.50
|
-0.50
|
120
|
|
Left Eye
|
-2.50
|
-0.25
|
45
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Please note: the dash
or minus sign in the sphere (SPH)
Laser Correction for Astigmatism
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Astigmatism is caused by an
unevenly shaped eyeball (like a rugby ball) and can be effectively
treated by laser. About half of glasses wearers have this added
problem.
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When an astigmatic person looks
at the spokes of a wheel, some spokes appear clearer than others.
Because only parts of the image are correctly focused, distortion
is caused at all distances. Astigmatism is shown on your glasses
prescription in the box marked CYL and is measured by the strength
of a cylindrical lens needed to achieve best vision.
AXIS shows the angle at which
astigmatism lies across the eye. The laser is set to remove more
tissue in the line of astigmatism. Laser eye correction treatment
is given immediately after short/long sight treatment, without
additional charge. Example of an astigmatic
prescription:
| Eye |
Sphere
|
CYL
|
AXIS
|
|
Right
Eye
|
-3.50
|
-1.50
|
120
|
|
Left Eye
|
-4.00
|
+2.25
|
60
|
Please note: CYL can
be measured as plus (+) or minus (-)
Laser Correction for Long Sight (Hyperopia)
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If you are long-sighted, the
focusing power of your eyes are too weak. You will be able to view
objects more comfortably at a distance than close up (less
than six feet).
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If your glasses magnify print,
you are long-sighted. In severe cases vision is not clear at any
distance. Treatment is still considered experimental by many
ophthalmic surgeons.
Optimax offers long sight laser treatment
only to those who are alerted to the risks and have moderate
expectations. Example of a long sight prescription:
|
Eye |
Sphere
|
CYL
|
AXIS
|
Right Eye
|
+2.00
|
-0.50
|
120
|
Left Eye
|
+2.50
|
-0.25
|
45
|
Please note: the
plus (+) sign for the sphere (SPH)
Reading Glasses (Presbyopia)
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There is currently no laser
vision correction treatment to eliminate the need for reading
glasses. This need is not due to long sight or short sight it is
the inability to focus close up when the eye muscles get older,
after middle age.
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Short-sighted people can remove
their glasses for close up work. Long-sighted people will need
reading glasses earlier in life. As with all normal-sighted
people, treated patients will still require reading glasses from
the age of about 45.