Rigid Gas Permeable Contact Lenses

Why rigid lenses see so well

A soft lens drapes over the cornea and adopts its shape, including its astigmatism and any irregularity. A rigid lens keeps its own precisely manufactured curve, and the tear layer between lens and cornea fills in the difference, so the eye's optical surface becomes the lens's front surface. That corrects regular astigmatism without a rotating toric design and neutralizes mild irregularity. Rigid materials are also optically purer and do not dehydrate, so vision stays consistent through the day.

Who suits RGP lenses

• Patients with moderate to high regular astigmatism who want stable, sharp vision
• Early to moderate keratoconus and other mild irregularity
• Patients after LASIK, PRK or RK, in reverse-geometry designs
• Patients who want the healthiest long term lens for the cornea, with high oxygen transmission and no dehydration
• Children and teenagers in myopia control, in orthokeratology designs worn overnight, where appropriate
• Presbyopic patients, in multifocal RGP designs that give excellent near and distance vision

Adaptation

A rigid lens is felt by the eyelid for the first days, and the eye waters and is light sensitive as it adapts. Wearing time is built up over one to two weeks, after which most patients are unaware of the lens. Once adapted, comfort is stable for years. Patients who cannot get past adaptation, or whose lenses decenter, are moved to hybrid or scleral designs.

Fitting and care

Corneal topography provides the curvature, a diagnostic lens is fitted and assessed with fluorescein, and the custom lens is ordered. RGP lenses are cleaned nightly with a dedicated solution and last a year or two. Because they are made to order and last, the yearly cost is often lower than for soft lenses.