The eye is connected to the brain via the optic nerve. The light that comes through the eye is interpreted as signals in the retina. These signals go through the optic nerve and eventually to the brain. The optic nerve is small (1.3” to 2.2”L and 1/5”W), however, it contains more than a million tiny nerve fibers much like a fiber optic cable. The reason why an eye transplant would be so difficult is due to the intricate connections. Once the connections to the brain are interrupted, it would be impossible for a surgeon to reattach them all.
In any transplantation, there are impediments to the process. These impediments of eye transplantation are restoring the circulation (to maintain the organ nourished), balancing the pressure of the eye, hence, maintaining the healthy composition of the eye and making sure there is no immunological rejection of the new organ.
Doctors can transplant many human organs, including the heart, lung, liver, kidney, hands, and parts of the eye. The most popular transplantation in the eye is corneal transplantation. Healthy corneas are clear making it easy for light to go through it. On the other hand, if a cornea has a scar, swelling irregular shape or dystrophy then it is very difficult for light to go through such a structure. A corneal transplant is an option for better vision. Other parts of the eye which can be transplanted are eyelashes for better protection of the eye or cosmetic reasons, amniotic membranes which can help in healing ocular tissues, lids and tear ducts. Researchers are now placing their focus on how to replace retinal cells with healthy transplants (stem cells) for the benefit of those with Macular Degeneration and Stargardt’s Disease.
We are a long way from an eye transplant. Science is unpredictable. Perhaps one of these days, we may be able to achieve transplantation of the eye successfully and largely do away with blindness.