Formula 1 legend Michael Schumacher is reportedly set to undergo a radical surgery as he continues to try and overcome a catastrophic head injury.
Schumacher's condition has been shrouded in secrecy ever since he suffered a head injury when skiing in the French Alps in 2013, but Italian media are reporting that French cardiologist Dr Philippe Menasche is set to perform a new stem cell operation to "regenerate his nervous system".
Dr Menasche, who is known as a "pioneer in stem cell surgery", is reportedly going to carry out the surgery on the motorsport legend's heart, with the procedure expected to take place in the next few days.
Menasche had earlier confirmed that Schumacher received heart and vascular surgery at the Paris Georges Pompidou Hospital, while last year he rejected claims he was "experimenting" on the seven-time F1 champion.
"I do not perform miracles," he said.
"My team and I are not doing an experiment, an abominable term that is not in line with a serious medical view."
Schumacher has been treated at home in a mansion in Switzerland since September 2014, and earlier this month, former Ferrari teammate Felipe Massa revealed he remains in a 'difficult phase'.
Speaking to Fox Sports Brazil about his former teammate's condition, Massa said: "I know how he (Schumacher) is, I have information".
"My relationship with him has always been very close. It is less close with his wife Corinna because she did not go to many races.
"But I think the main thing about all this is that we know that his situation is not easy.
"He is in a difficult phase but we need to respect him and the family."
In December, Kean-Francois Payen, who was the first to confirm Schumacher had come out of his coma five years ago, gave insight into the treatment he has been receiving, telling German publication In Touch "There is a one-to-three year plan for the regeneration period.
"I still visit him occasionally and talk to the family about any progress I see."
Dr Payen was limited in what he could expose around Schumacher's current state as he needed to "respect confidentiality".
But he did add Schumacher is making progress and in a positive state.
Payen heaped praise on Schumacher's wife Corinna, saying she has done everything necessary to help her husband recover, and credited her "extraordinary willpower" and awareness of what lies ahead.
"She sees things very clearly and will do anything to make her husband's condition better."