Eye bank Eye bank Eye banks recover, prepare and deliver donated eyes for cornea transplants and research. The first successful cornea transplant was performed in 1905 and the first eye bank was founded in 1944. Currently, in the United States, eye banks provide tissue for over 80,000 cornea transplants each year to treat conditions such as keratoconus and corneal scarring. In some cases, the white of the eye (sclera) is used to surgically repair recipient eyes. Unlike other organs and tissues, there is an adequate supply of corneas for transplants in the United States, and excess tissue is exported internationally, where there
Sclera pass. The thickness of the sclera varies from 1mm at the posterior pole to 0.3 mm just behind the rectus muscle insertions. The sclera's blood vessels are mainly on the surface. Along with the vessels of the conjunctiva (which is a thin layer covering the sclera), those in the episclera render the inflamed eye bright red. In many vertebrates, the sclera is reinforced with plates of cartilage or bone, together forming a circular structure called the sclerotic ring. In primitive fish, this ring consists of four plates, but the number is lower in many living ray-finned fishes, and much higher