The cornea is a transparent convex tissue that covers the front of the eye, which allows the entry of light into the organ. Its high optical features and extraordinary transparency are essential to proper vision.
There are times when the dome-shaped tissue is too prominent and irregular causing a disorder in its capacity to focus light on the retina. The optical properties of such conditions, which include Keratoconus and Pellucid Marginal Degeneration, can be improved with the implant of ring segments called INTACS. The visual function is thus improved (with or without the use of eye glasses) while increasing the eye's tolerance to contact lenses, without the need to perform a cornea transplant.
For cases of severe Keratoconus conditions, Pellucid Marginal Degeneration or situations where the transparency of the cornea is affected to the extent where there is loss of vision, a cornea transplant would be required. The damaged cornea is removed and replaced by a healthy and transparent one which is saturated into the recipient eye.
Opaque corneas can develop due to: scarring that results from severe infection, injury or burning; cornea edema caused by disease in any one of the layers that compose the eye; and corneal opacity (either congenital or appearing after birth).
Whatever the cause, the final results are always the same: loss of corneal transparency with subsequent loss of vision.