What is Eye Donation And Who Benefits?
Donation of human eyes and corneal tissue are necessary for the preservation and
restoration of sight and are used for transplantation, research and education.
Over 90% of more then 40,000 cornea transplant operations preformed each year
successfully restore vision to persons suffering from corneal blindness. Almost anyone
can be an eye donor. Cataracts, prior ocular surgery, diabetes, glaucoma, cancer,
poor eyesight, and age do not necessarily prohibit you from being a donor.
Cornea transplant involves replacing a cloudy cornea with a clear one from a donor eye.
A cloudy cornea may occur at any age. The cornea is the size of a dime and covers the
pupil of the eye, similar to a watch crystal that protects the clock face. If the cornea
becomes cloudy due to injury or disease,a clear image cannot be focused on the back of the eye, and blindness or near blindness can result.
Also other portions of the eye can be used in various procedures. Sclera - the white of
the eye - can be used in glaucoma surgery, lid repair and in periodontal surgery for the
repair of gum tissue.
What Is A Cornea?
The cornea is the clear dome shaped lens over the colored iris. The sclera, the white part of the eye, consist of the same tissue as the cornea; however the cornea is more hydrated which makes it clear in appearance. The cornea is the transparent window in the front of the eye that functions similarly to a watch face. The cornea has five layers and this amazing structure is only 500 microns (about 1/2 mm) thick. Each layer performs a specific function. The epithelium protects the cornea. Bowman's layer is a smooth membrane composed of strong collagen fibers that help the cornea maintain its shape. The stroma comprises 90% of the cornea and consists of collagen fibers. These fibers are transparent due to their alignment. Descemet's membrane is the basement membrane that lies between the stroma and the endothelium. The endothelium consists of cells which act as a pump to keep the cornea clear. We are born with roughly 4,000 of these cells which gradually die due to aging, injury, or disease. Once these cells can no longer keep the cornea clear, a cornea transplant is required to restore vision.
Healthy corneal endothelium UnHealthy corneal endothelium
