Transplants: Part of a whole eye —
After an attempted cornea transplant failed, ophthalmologists in Houston, Tex., tried a more daring experiment to restore the vision of 54-year-old John Madden…. They transplanted an entire eye from a donor who had died of a brain tumor.… [Later, the doctor who did the surgery] announced that only the front part of the donor’s eye had been transplanted; the back portion of Madden’s eye, including the optic nerve and part of the retina, had been preserved. — Science News, May 10, 1969
That partial eye transplant didn’t work, but researchers have made strides in restoring sight to people with some eye diseases, including an inherited form of blindness called Leber congenital amaurosis (SN: 5/30/15, p. 22). Nearly 185,000 corneas — the clear outer layer of tissue that covers the front of the eye — are transplanted worldwide each year, according to a 2016 survey in JAMA Ophthalmology. Yet, no one has successfully transplanted a whole human eye. Attempts in animals have had mixed success. In 2015, reconstructive surgeon Kia Washington of the University of Pittsburgh and colleagues transplanted part of a face, including an eye, from one rat to another. The eye survived.
Then in 2018, Washington, now at the University of Colorado School of Medicine in Denver, and colleagues confirmed that, in two of four rats with transplanted eyes, blood flowed normally to the retinas. The rats could not see from the transplanted eyes because surgeons had cut the rodents’ optic nerves, which carry information from the eye to the brain. Eye transplants may help wounded soldiers and other people who need facial reconstruction or transplants. More work is needed on how to regrow optical nerves to restore vision.