Science is slowly catching up with science fiction. Doctors can transplant the heart, lung, liver, kidneys and more recently hand transplants. Parts of the eye such as corneal transplants are also available.
The holy grail would be an eye transplant or the ability to regrow an eye with the help of stem cells. While there is no real prospect of achieving this in the near future there is continuing research working towards this end.
The three main impediments to transplanting a human eye are maintenance of donor eye viability, optic-nerve regeneration and restoration of topographic organisation, and avoidance of immunological rejection.
Reattaching the millions of nerves of the optic nerve to allow transfer of the information from the eye to the brain is the greatest impediment to achieving a viable eye transplant. If we are able to achieve this we still have the complications of restoring the circulation to the eye, balancing pressure of the transplanted eye and maintaining corneal health.
The earliest record of an eye transplant dates back to 1885 when a rabbit eye was transplanted into a human orbit. Since then there has been numerous attempts to transplant a mammalian eye. Although some of the studies establish “success” in other capacities, no visual function was recovered following transplantation.
There has been some success with eye transplantation performed in cold-blooded vertebrate.
A frog with the transplanted artificial eye on the left.
Professor Makoto Asashima of Tokyo University in Japan has used stem cell-like cells from a frog embryo to grow complete eyes which were then successfully transplanted into tadpoles.
Professor Asashima believes that his groundbreaking research could pave the way for the same procedure to be used to restore vision in humans.
So far, Professor Asashima and his team have transplanted new eyes into about 60 tadpoles, of which nearly three-quarters could then see. And 7 of the transplanted eyes have survived the metamorphosis from tadpole to frog.
More recently Embryonic stem cells from mice have been transformed into a rudimentary eye. The eye was not grown to the fully developed stage but raises hopes of growing parts of the human eye to investigate and treat blindness.
One of the concerns people have when faced with the prospect of having an eye removed is whether they are going to be able to have an eye transplant if / when the technology becomes available.
A message that comes through in all the articles I have read on this topic is that while we are hopeful that this technology will be available one day, it is not something that will be available in the near future.
Ophthalmologists I have talked to about this have advised that talk of eye transplants and bionic eye replacements is only giving people false hope and the technology is still very much in the realm or science fiction.
I feel that while it is important to be realistic about prospect of eye transplant technology being available in my life time, it is encouraging to see that there is research being done in this area.
You can read more about Professor Makoto Asashima and his transplanted frogs eyes Here
Information on the” Simple eye grown from stem cells” can be found on the Guardian website Here
