CLEVELAND (Ohio) - DOCTORS hailed the first US face transplant as a means for the severely disfigured to 'face the world' without humiliation on Wednesday in announcing the successful replacement of 80 per cent of a woman's face.

VIDEO A new face forward (1:37)

It was the world's first near-total facial transplant and the fourth known facial transplant to have been successfully performed to date.

Doctors released few details about the patient, save to say that she had been disfigured to the point where she could not eat or breathe on her own as a result of a traumatic injury several years ago.

They said the woman, who did not wish to be identified, had exhausted all conventional reconstructive surgery to replace her nose and rebuild her mouth, cheeks and lower eye sockets.

They hoped the operation would allow her to regain her sense of smell and ability to smile and said she had a 'clear understanding' of the risks involved, including that her body could reject the new face.

Facial transplants are controversial because they carry heavy risks and are performed to improve a patient's quality of life rather than as a life-saving operation.

There are also concerns that the operation could eventually be used for purely cosmetic purposes or as a means of altering someone's identity.

Doctors at the Cleveland Clinic stressed that such operations should be limited to a medical context in order to free severely disfigured people from the suffering associated with social isolation.

'We need the face to face the world,' said lead surgeon and researcher Maria Siemionow.

'There are so many patients there, in their houses, where they are hiding from the society because they are afraid to walk to the grocery stores. They are afraid to go to the streets, because they're called names, and they are humiliated.'

'So we very much hope that for this very special group of patients, there is a hope at one day they will be able to go comfortably from their houses and enjoy the things which we take for granted.'

Doctors in France performed the first partial face transplant in 2005 on a 38-year-old woman, Ms Isabelle Dinoire, who was disfigured in a dog attack.

In 2006, a Chinese man underwent a facial transplant including the connection of arteries and veins, and repair of the nose, lip and sinuses. A bear had mauled the 30-year-old farmer as he looked for stray sheep.

A 29-year-old man French man underwent surgery in 2007. He had a facial tumor called a neurofibroma caused by a genetic disorder.

The tumor was so massive that the man couldn't eat or speak properly.

The Cleveland Clinic became the first US hospital to approve the procedure four years ago.

The woman showed no early signs of rejecting the face following the 22-hour operation conducted a few weeks ago, doctors said. She is still having trouble speaking and will require months of intensive physical therapy.

She has not seen herself in the mirror yet and will likely also require counseling to adjust to her new appearance, doctors said.

Her sibling issued a statement thanking the donor and the medical team.

'We never thought for a moment that our sister would ever have a chance at a normal life again, after the trauma she endured,' the sibling said.

'But thanks to the wonderful person that donated her organs to help another living human being, she has another chance to live a normal life.' -- AFP