Surgeons in the United States have carried out America's first face transplant at a clinic in Cleveland, Ohio where a woman has had 80% of her face replaced with that of a deceased female donor.
The operation which was conducted by reconstructive surgeon Dr. Maria Siemionow along with a team of seven other doctors, is only the fourth worldwide to be carried out - two have been conducted in France and one in China.
The first patient to receive a face transplant was Isabelle Dinoire, who underwent the surgery in 2005 when she was 38, after she had been mauled by her Labrador retriever - French surgeons grafted onto her face a nose, lips and chin from a donor who had been declared brain-dead.
In 2006, a 30-year-old Chinese farmer underwent a facial transplant including the connection of arteries and veins, and repair of the nose, lip and sinuses after he had been mauled by a bear and in 2007 a 29-year-old man French man underwent surgery following a facial tumour called a neurofibroma so massive that the man was unable to eat or speak properly.
The successful U.S. procedure took place recently on a patient who had been disfigured by a traumatic injury but no further information about the patient has been released.
Controversy surrounds surgery such as facial transplants which are considered to be experimental; they carry significant risks and they aim to improve a patient's quality of life rather than as a life-saving procedure.
The risks include failure of the transplanted tissue and complications from anti-rejection drugs, which the patient must take for the rest of their life and should the anti-rejection drugs fail, surgeons have few alternatives to offer the recipient.
However transplant pioneers believe that the psychological effects of facial damage from injuries, birth defects and a number of diseases can be devastating and they say as long as the patients, donors and their families understand the risks, the benefits of an experimental face transplant may outweigh the drawbacks.
The Cleveland Clinic became the first American hospital to approve the procedure four years ago.