Keratoconus frequently appears in the teen years and early twenties. This eye disease is aggressive and is condition where cornea, round in shape, thins and starts to bulge outward into a shape resembling a cone. As light enters through the pupil into the eye, this cone-like shape reflects it before it reaches the retina; this causes the vision to be distorted. This condition can occur in just one eye or both.
Symptoms and Signs:
Keratoconus is difficult to detect at times. This is because of its slow development, but a slow progression is not always the case, it could progress quickly. As the cornea’s shape continues to change and become more irregular, it causes what is known as progressive nearsightedness and as a result irregular astigmatism develops. This causes additional problems and as a result blurred and distorted vision occurs. Sensitivity to light and glare will most likely be noticed as well. Prescription changes are common, if not the routine for a keratoconic patient at every eye examination. A diagnosis of keratoconus is commonly delayed in being diagnosed because symptoms during the early stages of the disease are not easily detected.
What Causes Keratoconus?
Recent research suggests corneal tissue weakening is what leads to keratoconus and may be the cause of an imbalance of enzymes inside the cornea. The cornea is more apt to have oxidative damage caused by free radicals; this is what causes the cornea to become weak and bulge outward. This condition is hereditary and may run in the family. The sun’s ultraviolet rays, contact lenses poorly fit continuously, chronic eye irritation, and rubbing the eyes excessively have also been associated with the keratoconus.
For mild keratoconus – eyeglasses can help as may soft contact lenses, if the condition doesn’t worsen too badly. As the cornea becomes thinner and the irregular shape increases, simple glasses or contact lenses will no longer adequately correct the vision.
Moderate to Advanced Treatments:
Gas Permeable Contact Lenses – RGP (Rigid gas permeable) contact lenses are eye doctor’s choice of treatment when eyeglasses or soft contact lenses do not control an eye’s keratoconus. These contact lenses’ rigid material allows RGP lenses to reshape the cornea by lying over the cornea, replacing “what’s missing” from the cornea's shape with a smooth, cylindrical surface and improves vision. RGP contacts are not as comfortable for a wearer as the soft contact lenses they may be used to. The fitting for RGP’s is time consuming and can be difficult to fit properly. Many visits may be needed before finding the right style for the wearer. If the condition worsens it can make fitting proper RGP contact lenses even more difficult if not impossible.
Piggy Back Contact Lenses – This is fitting two different types of gas permeable contact lenses over cone-shaped corneas on one eye; first a soft contact lens is placed on the eye and then another on top called a GP lens. Doing this increases the comfort a wearer experiences because the soft one acts as a cushion.
Hybrid Contact Lenses – Hybrid contact lenses – fairly new design – combines a soft peripheral "skirt and a highly oxygen-permeable rigid center – wide variety of parameters available.