A man presumed to have been in a deep coma for 23 years has hailed his “second birth” after doctors realised that he had been fully conscious all along but unable to communicate.

Rom Houben, 46, was paralysed in a car accident and declared to be in a persistent vegetative state, while in fact he remained aware of his surroundings and could hear his doctors gradually give up hope on him.

Researchers using new diagnostic techniques discovered that his brain was still active and trained him to use his right forefinger to express himself on an adapted keyboard.

Mr Houben’s case is being highlighted in his native Belgium by doctors who are pioneering new ways of understanding coma patients, hundreds of whom around the world could actually be conscious but locked in paralysis — and able to feel pain, unlike a true coma patient.

“I shall never forget the day when they discovered what was truly wrong with me — it was my second birth,” Mr Houben tapped out on his keyboard at the nursing home east of Brussels where he still needs constant care. “All that time I just literally dreamt of a better life. Frustration is too small a word to describe what I felt.”

Mr Houben had been written off as being in an “extinct” state after the athletic former martial arts enthusiast, keen wind-surfer and engineering student was gravely wounded in a car crash in 1983 when aged only 20.

Asked what he felt, Mr Houben said: “Powerlessness. Utter powerlessness. At first I was angry, then I learnt to live with it.”

His reawakening came three years ago thanks to coma specialists at Liège University Hospital who have spoken this week about the case for the first time to try to draw attention to the condition and save other misdiagnoses.

They say that as many as four in ten who have been termed as being in a persistent vegetative state may be conscious some of the time.

Mr Houben, who is still paralysed and dependent upon carers around the clock, recalled the terrifying realisation after he came round from his accident when he knew that he had lost complete control of his body — and no one knew that he was fully conscious.

“I screamed, but there was nothing to be heard,” he told the German magazine Der Spiegel.

“I became a witness to my own suffering as doctors and nurses tried to speak with me until they gave up all hope.” Asked how he passed the time for 23 years, he said: “I meditated — I dreamt myself away.”

His bed has now been equipped with a book holder above his face so that he can read while lying down. “I can read and communicate with my friends by computer now that people know I’m not dead,” he said.

Doctors had given up on Mr Houben because he showed no physical reaction to various stimuli including loud hand-clapping and familiar voices. Dr Steven Laureys, a neurologist at the Liège University Hospital, discovered with the help of brain scanning techniques not available at the time of his accident that Mr Houben’s cerebral cortex was still active.

The breakthrough came when he was able to indicate yes or no by nudging a computer device with his foot. Mr Houben’s condition has since been diagnosed as “locked-in syndrome” where patients are unable to show that they are conscious.

Dr Laureys and his colleagues carried out a 16-month study of coma patients and found that 41 per cent of those termed as being in a vegetative state showed signs of consciousness.Many doctors were not aware of a new diagnosis of “minimally conscious”, which reflects occasional signs of life such as eyebrow flickers — but the difference can determine whether life support machines are switched off.

“Misdiagnosis can lead to grave consequences, especially in end-of-life decision-making,” Dr Laureys said.

Mr Houben’s mother never gave up hope. “I always knew our son was still there,” she said, adding that he is writing a book. “He lives from day to day,” she said. “He can be funny and happy”, but is also given to black humour.

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