Please be advised that this information is meant to be informative and not intended for self-diagnosis.
Only your eye care professional can provide you with an accurate account of your current visual health.
WHAT IS THE CORNEA?
The cornea is the normally clear, front window of the eye that covers the colored iris and round, dark pupil. Light is focused while passing through the cornea, allowing us to see. A healthy, clear cornea is necessary for good vision. If your cornea is injured or affected by disease, it may become swollen or scarred, and its smoothness and clarity may be lost. Scars, swelling or an irregular shape can cause the cornea to scatter or distort light, resulting in glare or blurry vision.
CONDITIONS AFFECTING THE CORNEA
There are many conditions that can affect the clarity of the entire cornea. For instance, trauma or injury to the cornea can cause scarring, as can infections (especially herpes keratitis). A hereditary condition called Fuchs' dystrophy causes corneal failure. Keratoconus causes a steep curving of the cornea. Sometimes corneal failure can occur after an eye surgery such as cataract surgery.
WHEN IS A CORNEA TRANSPLANT NEEDED?
A corneal transplant is needed if vision cannot be corrected satisfactorily with eyeglasses or contact lenses, or if painful swelling cannot be relieved by medications or special contact lenses. A corneal transplant is done using a human donor cornea. Before a cornea is released for transplant, tests are done for infectious diseases and the cornea is also checked for clarity.
CORNEA TRANSPLANT SURGERY OPTIONS
With traditional full corneal transplant surgery (known as penetrating keratoplasty), a circular portion is removed from the center of the diseased cornea. A matching circular area is removed from the center of a healthy, clear donor cornea, placed into position and sutured into place. With an EK cornea transplant procedure (endothelial keratoplasty), only the abnormal inner lining of the cornea is removed. A thin disc of donor tissue containing the healthy endothelial cell layer is placed on the back surface of the cornea. An air bubble pushes the endothelial cell layer into place until it heals in an appropriate position.
THE GIFT OF SIGHT
Corneal transplant would not be possible without the thousands of generous donors and their families who have donated corneal tissue so that others may see. Each year, nearly 50,000 people with corneal disease are given the gift of sight through cornea donors.