Specialized Contact Lenses
Contact lens wear may be more difficult if you have certain preexisting conditions. However, we are often able to find a successful solution through our comprehensive specialty fittings. Below are a couple of examples of situations and possible contact lens solutions.
Contact Lenses for Keratoconus
Keratoconus is a progressive disease that involves the thinning and steepening or "bulging" of some, but not all, of the cornea. The area affected is usually at or near the center of the cornea. In keratoconus, the cornea becomes very irregular in shape and increases in astigmatism. Because of the cornea's unusual shape, eyeglasses and soft contact lenses can't fully correct vision to an acceptable level.
About 15% of keratoconic individuals ultimately require a corneal transplant, but most can benefit from wearing GP contact lenses.
Piggy Back Lenses
Sometimes, GP lenses will provide excellent vision for a person with keratoconus, but the wearer finds the rigid lenses uncomfortable and cannot wear them for an entire day. In these cases, a fitting technique called piggybacking may be used. In piggybacking, a soft contact lens is worn under the gas permeable lens, acting as a cushion to reduce or eliminate any discomfort caused by the GP contact lens. Hybrid Contact Lenses Hybrid contacts are large-diameter lenses that have a rigid gas permeable central zone, surrounded by a peripheral zone made of soft or silicone hydrogel material. The purpose of this design is to provide the visual clarity of GP lenses, combined with wearing comfort that is comparable to soft lenses. This lens have a special design that enables the central GP zone of the lens to vault over the irregularly shaped cornea. |