A Russian man aiming preparing to undergo the world's first head transplant operation has denied he is "crazy" for agreeing to take part.
Computer programmer Valery Spiridonov will fly to New York to meet neurosurgeon Sergio Canavero for the first time this week.
He hit out at people who claimed the operation was an elaborate hoax and insisted Canavero was "not playing games with the concepts of life and health".
Spiridonov suffers from a muscle-wasting condition called Werdnig-Hoffman disease and has spent much of his life in a wheelchair.
"I am not rushing to go under the surgeon's knife, I am not shouting - come and save me here and now," he told Mail Online.
"Yes, I do have a disease which often leads to death, but my first role in this project is not that of a patient.
"First of all, I am a scientist, I am an engineer, and I am keen to persuade people - medical professionals - that such operation is necessary.
"I am not going crazy here and rushing to cut off my head, bel
"The surgery will take place only when all believe that the success is 99 per cent possible."
Critics doubt the surgery will be a success, because the technique is so far unproven.
President elect of the American Association for Neurological Surgeons Dr Hunt Batjer said: "I would not wish this on anyone.
"I would not allow anyone to do it to me as there are a lot of things worse than death."
Head transplant patient says he and controversial doctor are 'making science'
Far from being anxious, Russian Valery Spiridonov has told Sky News: "We are making science."
Computer programmer Valery, who suffers from a muscle wasting disease, is meeting with a neurosurgeon from Italy called Dr Sergio Canavero.
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If Dr Canavero and Valery agree to go ahead with the procedure, it could happen in 2017.
The pair are speaking at the American Academy of Neurological and Orthopaedic Surgeons in Annapolis, Maryland.
But not everyone feels that the operation is a good idea - with some even labelling it a hoax.
Valery said in an interview with Mail Online last week: "I am not going crazy here and rushing to cut off my head, believe me.
Writing in the scientific journal Surgical Neurology International, Dr Canavero revealed that the patient's head would be packed in ice to help it survive once it is detached to keep the brain cool.
It will then be reattached to a donor body in stages, although fusing spinal cords is something which has never been done successful
According to reports, Dr Canavero plans to douse the ends of the cord in polyethylene glycol to boost the changes of the nerve cells sticking together via their fatty tissue.
There will then be an induced coma of up to a month to allow the head to heal in absolute stillness.
Confident of his claims, Dr Canavero says that his patient should be able to walk within 12 months, and he's testing his technique on brain-dead organ donors.
He is however aware that ethical considerations may prevent the operation from going ahead in the West.