Rigid Contact Lenses
First produced in the late 1800s, rigid or hard contacts were the first type of contact lenses to be used. They were
manufactured then from hard Plexiglas types of plastic, but have evolved now into semi-hard silicone types of plastic called
gas-permeables. These small buttons of plastic allow necessary oxygen and gases to reach the cornea or the clear window of
the eye. Although the typical period required by the patient to adapt to hard lenses is longer initially, the superior
optics and ease of maintenance of the rigid gas-permeables often make them the desirable choice for vision correction. Some
types of astigmatism, an irregular curvature of the eye, can only be corrected with gas permeable lenses. Another advantage
is that they can last for years with proper care. A trial fitting is necessary to determine the prescription.
Most rigid gas-permeable lenses are for daily wear. It is extremely important when storing lenses to clean the case and
change the solution every day. The disinfecting solutions are not strong enough to last more than a day.
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