Italian surgeon Dr Sergio Canavero.
Thirty-year-old Valery Spiridinov hopes to have his head transplanted on to another man's body in 2017 but some doctors have doubts.
Spiridinov, from Russia, suffers from Werdnig Hoffman disease, a muscle wasting condition. He has announced his intention to become the world's first subject of a full head transplant, so
that his brain can be attached to a healthy body.
Italian neuroscientist Dr Sergio Canavero, who leads the Turin Advanced Neuromodulation Group, first announced his project in 2013, saying at the time that such a procedure could be possible by 2016. But this timeline seems extremely unlikely given the numerous obstacles and gaps in knowledge. Other doctors have expressed serious doubts, and, in particular, the likelihood that Spiridinov's brain will still be functional by the time the surgery is complete.
Matthew Crocker, consultant neurosurgeon at St George's Hospital, London, told Sky News that every section of the operation has a grounding in current science and practice - at least in theory. "Excluding blood vessels that supply blood to the brain then restoring them with tubes is very well recognised. Lowering the temperature of the whole body head and brain to between 10 and 20 degrees is ... used for complex neurosurgery or cardiovascular surgery. The idea of cutting the spinal cord sharply rather than bluntly has a little medical support. At what point does one die, might be one for an ethicist to consider. But the heart is routinely stopped in open heart surgery."
One stage involves knitting together blood vessels and nerves, and Crocker said he doubted whether the feat had ever been attempted on such a scale successfully before. The body is then kept in a coma for several weeks to prevent movement and allow time for the spinal cord to glue back together. "That is very speculative," Crocker said. "The issue here is that someone with a functioning spinal cord is facing having that function completely removed."
