Scientists have made huge strides in transplantation techniques. People routinely receive new hearts, lungs, livers, and kidneys. There have been hand transplants and even a small number of face transplants.
But one organ that has remained impossible to transplant is the eyeball.
That’s because it’s been necessary to connect the donor eye to the severed optic nerve in the recipient eye socket. This is some seriously complicated work, given how thin each nerve fiber is, and given that it has been sliced on both sides.
What we should say is that up until now it has been necessary to reconnect the optic nerve when transplanting eyes.
Scientists published a study last week in the journal Regenerative Medicine. They reported that it is possible to transplant eyes, and possibly other sensory organs, into different parts of the central nervous system, as long as they are manipulated properly.
The study hopes to show that the central nervous system is able to create new nerve pathways between sensory organs and the brain. In the case of the eye, they want to show that an eye grafted onto the lower end of the spine can actually send visual information all the way to the brain, and that the brain can figure out what that information means.
One of the investigators, Michael Levin, explained:
We’re asking questions about the plasticity of the brain. If you do make anatomical changes in the body plan, how can the brain adjust to that?”
So how did these researchers approach the problem?
They grafted little frog eyeballs onto the tail sections of tadpoles. By controlling the electrical environment around the new nerve cells, and by manipulating the serotonin exchanges between the cells, those eyes were able to see.
While this study might seem just a little bit creepy, with tadpoles watching the world out of their backsides, it holds a great deal of promise for the future of transplant medicine. Imagine how amazing it would be if doctors could find a way to help the blind to see.
Even they are seeing the world through a vastly different perspective.
See the science in action below.
Featured image via YouTube Screengrab.