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Astigmatism sufferers had few options until now. Not only can you wear rigid gas-permeable lenses, but soft contact lenses are
now available that will correct your astigmatism.
What is Astigmatism?
Astigmatism usually occurs when the cornea is irregularly shaped, appearing more like a football than a basketball. Like a
football (or a spoon), an astigmatic eye has unequal curvature in different meridians. In contrast, a basketball is a perfect
sphere with equal curves in all meridians. Because the cornea is curved more in one meridian than in the other, light rays
focus at different places depending on their orientation, and objects at all distances appear blurred.
Rigid Gas Permeable Lenses
As their name implies, rigid gas permeable (RGP) lenses are hard lenses. Because rigid lenses retain their shape on the cornea
better than soft lenses, they tend to provide crisper vision to people who have mild astigmatism.
In cases of moderate to severe astigmatism, a standard rigid gas permeable contact lens may be uncomfortable or unstable on the
eye because the shape of the cornea is so irregular that the contact lens doesn't center properly on the eye and moves (or "rocks")
too much during blinks. In these cases, a toric RGP contact lens may be used.
Soft Toric Contacts
Toric soft lenses are a special type of soft contact
lens that have different curves in different meridians to correct the astigmatism. Special weighting and/or thin zones in toric lenses
keeps the proper lens meridian in front of the corresponding meridian of the eye and prevents the lens from rotating during wear.
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