AK's
Nearsightedness and farsightedness are adjusted
by the new lens implant. Astigmatism is not corrected by the implant
but can be improved by astigmatic keratotomy (AK). What is astigmatism?
It means the cornea (the front surface of the eye) is NOT round.
AK can improve this condition by making small incisions in the steep
axis (tight axis) of the cornea.
Astigmatism
With astigmatism, an abnormal curvature of the
cornea in one direction causes light travelling in one plane, the
vertical red plane in this case, to focus in front of the retina
(red arrow). The light striking the retina through the vertical
plane is out of focus on the retina and vision is unclear.
The AK Procedure
The Astigmatic Keratotomy procedure (AK) uses two
small incisions (blue lines) made in the cornea in the steep axis
which effectively "flattens" that axis of refraction.
The Result
The "flattening" of the steep axis of the cornea resulting from the two corneal incisions (green arrows) now causes light in the vertical plane (red) to focus on the retina (red arrow). Vision becomes clear.
Click here for more information on AK (Astigmatic Keratotomy)
