ASTIGMATISM AND
LASER SURGERY: IS IT REALLY EFFECTIVE?
Progress in
the ophtalmologic surgical technique has allowed phyicisians to perform them
routinely and with very limited risks; a few years ago, these interventions
would not have been even dreamt of.
With very slight pains and only in a few minutes, problems such as
short-sightedness, longsightedness or astigmatism can disappear permanently.
Astigmatism
is a refraction defect due to the different size of the two cornea axis: one
of them is more curved and the other one, more even. This means that images
that come to the retina are out of focus. In
hipermetropic astigmatism, one axis focus in the retina and the
other on its back. When one of the axis projects before the retina, we have
a case of miopic astigmatism. If none
of these axis coincide with retina, we have a case of
mixed astigmatism.
The procedure
known as Laser Assisted in Situ Keratomileusis (LASIK)
is the most effective and safe technique that exists nowadays for the
correction of astigmatisms not higher than 6
dioptries. This is the most currently used procedure, since 90% of
the patients have an astigmatism of this degree. The LASIK modifies the power of
the cornea, which is the main lens of the eye. The cornea has three main layers:
epithelium, stroma and endothelium. The LASIK modifies the estroma curve in
order to reshape the cornea.
The advantage the LASIK has over other laser procedures is that the carving is
made in the deep layers of the corneal stroma.
This procedure is performed by means of topic
anestesia (eye drops) and it is very
easy (it takes only a few minutes).
As any surgical
procedure, it entails some risks, even though the impact of complications is
scarse thanks to the current techniques. Sometimes, it is necessary to repeat
the procedure, applying the same technique (Laser Assisted in Situ
Keratomileusis - LASIK), in order to
obtain an optimum result.
Translation: Sabrina Gisella Cordone.
Más información en
http://www.portalesmedicos.com/traductores-medicina/cordone/ |