Michael Schumacher's doctor has revealed details over the treatment the motorsport legend has been receiving since his skiing accident in France six years ago.
The seven-time Formula One champion has not made a public appearance since the accident in 2014 where he suffered a serious head injury, with his family furiously keeping him behind closed doors while he recovers.
Kean-Francois Payen, who was the first to confirm Schumacher had come out of his coma five years ago, has given 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."
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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 will power" and awareness of what lies ahead.
"She sees things very clearly and will do anything to make her husband's condition better."
Professor Philippe Menasché also confirmed to the German publication that Schumacher received heart and vascular surgery at the Paris Georges Pompidou Hospital.
"There he was subjected to cell therapy.
"But it was clear from the outset that no miracles would happen to him during therapy."
Corinna remains committed to the former driver.
"He did everything for me. I will never forget who I have to thank.
"That would be my husband Michael," she told She magazine.
In January the family provided an update on his health.
"You can be sure that he is in the very best of hands and that we are doing everything humanly possible to help him," they said in a statement.
"Please understand we are following Michael's wishes and keeping such a sensitive subject as health, as it has always been, in privacy."
The Schumacher family's long-term media adviser said in October she still sees Michael and Corinna Schumacher as a "perfect couple".
"They were such a perfect couple and they are still a perfect couple if you ask me," she said.
Schumacher has been treated at home since September 2014.