Specialty Contact Lenses for Keratoconus & Irregular Corneas: RGPs, Hybrid Contacts, Scleral Lenses

TopographerA computerized corneal topographer is a special non-invasive instrument used to diagnose certain diseases of the cornea and ocular surface. The cornea is the front anatomical structure of the eye and the first layer of the eye responsible for focusing light and vision. Some corneal diseases, such as keratoconus, pellucid marginal corneal degeneration, etc., are sometimes not easily detected by gross examination, but rather require topographical imaging, which scans and maps out the curvature of the cornea. This helps your optometrist confirm or rule out the diagnosis of these corneal conditions.

Once diagnosed with the appropriate corneal disease, your eye doctor can determine the ideal options to give you the best quality vision. With these certain conditions, the corneal surface is irregular. Thus, patients experience distortion, double vision, glare, haloes, and blur with soft contact lenses and glasses because light can no longer focus properly through the eye. Specialty contact lenses maintain their rigid shape as they curve over the cornea and ocular surface. Thus, the specialty contact lens resembles regular, rounded surface to provide better optics and vision; they include rigid gas permeable contacts, hybrid contacts, and scleral contacts.

The most common corneal disease to be fit with specialty contact lenses is keratoconus. Keratoconus is a progressive disease of the cornea, where the cornea becomes thinner with time due to a weakening of collagen fibers. As keratoconus progresses, the cornea begins to bulge outward and takes on a more cone shape. The age of diagnosis can range from approximately 10-30 years old. In mild cases, soft contact lenses and glasses can still deliver good vision, but as the disease progresses, specialty contact lenses are the best option.

At Grand Vision Optometry, we offer multiple choices of specialty contact lenses to suit your unique corneal needs:

  • Rigid gas permeable contact lenses (RGPs) are small lenses that rest on the cornea. They provide clearer vision than glasses and soft contact lenses. Under certain circumstances, RGPs may move around or dislodge due to their size.
  • Hybrid contact lenses are a bit larger in diameter due to their design that rests on the cornea. They have a soft peripheral lens edge and rigid center to combine better vision and comfort to resemble the comfort of a soft contact lens and superior vision of an RGP.
  • Scleral contact lenses are another comfortable larger diameter contact lens that acts a prosthetic to completely arch over the cornea, which act to mimic a normal ocular surface especially for patients with advanced keratoconus. They are less likely to dislodge from the eye and have better stability.

-Dr. Iris Wong

Grand Vision Optometry 151 S Las Posas Rd Ste 171, San Marcos CA 92078. Tel: (760) 510-3130