Ophthalmic Technician

Answer: D - All of the above

Although not commonly prescribed, in certain cases ridged gas permeable contact lenses are preferred over soft lenses. In severe cases of dry eyes, astigmatism, and irregularly shaped corneas, ridged gas permeable lenses are used because they are able to replace the natural shape of the cornea with a new refracting surface. Because it will take the patient some time to get adjusted to this type of contact lens, it is important to discuss with the patient how the experience is different form wearing soft lenses.