A terminally-ill Russian man may soon get a new lease of life as a medical team aims to perform the world's first head transplant on him in December 2017.
31-year-old computer scientist Valery Spiridonov suffers from Werdnig-Hoffman disease, which causes muscles to waste away. The condition has also left him wheelchair-bound.
In 2015, he volunteered to be the first man to have his head transplanted onto a donor body, in a controversial procedure championed by Italian neurosurgeon Dr Sergio Canavero.
The highly-complex operation involves severing the heads from the spinal cords of both the patient and the donor at the same time, before attaching the patient's head to the donor's body.
Polyethylene glycol, a glue-like substance, would be used to fuse the two ends of the spinal cord, according to Daily Mail UK, after which a metal plate is inserted to stabilise the new neck while muscles and blood supply are reconnected.
The patient will then be placed into a four-week long coma to prevent movement while the head and body heal together.
To prevent the new body from rejecting the head, the patient would be given strong immunosuppressant drugs.
If the head transplant is successful, it may bring hope to others who are disabled or paralysed.
Since 2013, Dr Canavero and his Chinese counterpart, Professor Ren Xiaoping from Harbin Medical University, have been conducting experiments on live animals and refining their skills in order to obtain the best outcome.
They claim to have successfully performed head transplants on several mice and a monkey, which reportedly survived for up to a day.
Earlier this year, Professor Ren also said that his team have progressed to conducting studies on human cadavers.
After the announcement of their head transplant plans, medical experts worldwide have expressed concerns that the procedure is pushing the ethical and practical limits of science.
Some of them have called Dr Canavero's plans "pure fantasy" and added that he had simplified the challenges of reattaching a spinal cord.
However, the huge risks involved in a head transplant do not seem to deter Mr Spiridonov, who fears that he wouldn't live long enough to "see it happen to someone else."
According to The New York Times, several other severely disabled patients in China have also volunteered to undergo head transplants.
Dr Canavero estimated that the 36-hour surgery would require a team of 150 doctors and nurses and cost US$100 million (S$134 million).