is a stigmatism and how it can be corrected with
toric contact lenses?
toric contact lens
Actually it is not a stigmatism, but an
astigmatism. It is a condition of the eye
when cornea, lens, or both are irregularly shaped so that
images aren't focused sharply on the retina. As a result,
the eye has different focal points in different planes.
For example, the image may be clearly focused on the retina
in the horizontal plane, but in front of the retina in the
vertical plane. So a person with astigmatism sees objects
blurred at any distance.
Astigmatism is one of the
most common vision problems. Usually it is a hereditary
condition. It can also be caused by an eye injury that has
caused scarring on the cornea, from some types of eye surgery,
or from keratoconus, which is disease that causes a gradual
thinning of the cornea.
Soft toric and RGP lenses can correct astigmatism
A few years ago the only solution for people with stigmatic
eyes was RGP (ridged gas permeable) lenses. Now your choices
Regular RGP lenses (for
mild case of astigmatism)
Toric soft contact lenses
RGP lens as the name suggests is a hard lens.
It They maintain its shape on the eye and don’t take
the unequal contours of an astigmatic eye like soft lenses
Ordinary RGP lenses are quite good for correcting
not severe astigmatism, however,
if the cornea is a very irregular shape a lens might become
uncomfortable and unstable. In this case you need special
toric RGP lenses. A toric RGP lens has a special-shaped back
surface and matches the irregular shape of the eye more closely.
That provides more stable and comfortable fit. It also keeps
the lens from rotating on the eye.
lenses are a recent development for astigmatism correction.
They are more comfortable to wear than RGP lenses. Toric soft
lenses are a special type of soft contact lens that has different
curves in different meridians. Also the lens is usually heavier
at the bottom, which prevents its rotation in the eye.
RGP of soft toric: which is better?
Both soft and RGP toric lenses are doing a very good job
correcting astigmatism. RGP lenses last longer, so they
are more cost-effective solution.
On the other hand, most soft toric lenses are 1-2 week
disposables. And the more often you replace your lens –
the healthier for your eyes. Also if you lose a soft toric
lens it is not a big deal, just replace it with new.
Another advantage of soft toric contacts that they now
also come in colors. The most popular color variety is Freshlook
Colorblends Toric. So you can not only fix your vision,
but also change the color of your eyes.
Which is better for astigmatism colored or clear
It makes absolutely no difference. Color toric lenses have
exactly the same design as clear soft torics, except for
the layer of color.