CHICAGO — The very first near-full human face transplant was detailed Friday by the surgeon who performed the procedure.

In December, plastic surgeon Maria Siemionow, after years of extensive research on mice and cadavers, transplanted almost 83 square inches of skin, with the muscles, bone, upper lip and nose still attached from an anonymous donor onto a young woman who the doctor said "did not have a midface" after she sustained traumatic injury.

After two months, the patient, whose name and likeness remain private, has experienced return of basic functions, like the sense of smell and the ability to drink from a cup. She has been discharged from the hospital and appears to be recovering.

"She didn't have a nose," Siemionow told a room full of her colleagues here at the American Association for the Advancement of Sciences annual meeting. "Now, she can eat a hamburger and smell it and taste it."

Heart, liver, kidney and even lung transplants have become common surgical procedures, but transplants of pieces of the body that contain many types of cells — skin, muscle and bone, for example — are much more difficult. The first hand transplant occurred in 1999. French scientists carried out the first partial face transplant in 2005. The new procedure, however, is far more involved: Siemionow transplanted 80 percent of the woman's face from the donor.

The surgeon and her research team had spent years laying the groundwork for the procedure with time-consuming operations in animal models. A full facial transplant in a mouse takes a team of surgeons more than six hours. Over the last decade, the Cleveland Clinic team has completed more than 1,000 facial transplants of different types in mice to learn about the body's parameters for rejecting the foreign cells. White mice usually receive brown-furred facial transplants or vice versa, so the mice often look as if they are wearing leather helmets or *Phantom of the Opera-*style masks after the operations.

In preparation for the human transplant, Siemionow and her colleagues did similar procedures with cadavers.

No one in the audience reacted to the graphic nature of the images of the procedure, including the images of the faces which had been harvested from the cadavers, the skin splayed out like masks.

Siemionow emphasized that the full facial transplant is a last resort for a "very specific" type of patient. Patients who need an entirely new face have limited options. They can have skin grafted onto their faces from their own bodies, but the skin from the thighs, arms, abdomen and other common sources look slightly different, producing the unsightly quilt-like effect that is familiar from burn-victim photographs.

To avoid that problem, Siemionow looked into using one contiguous piece of skin from some other area on the body, but their research showed that no area of the patient's own body contains the necessary 100 square inches of skin necessary to cover the whole face. For a full facial skin transplant, there's no alternative to using a donor, Siemionow argues.

Ethical questions have been raised about the procedures. While the transplant appears to have improved the first patient's quality of life, the immunosuppressants that the patients have to take for the rest of their lives could be unsafe.

"One case is merely an anecdote. It doesn't create a scientific basis to say it's safe for a patient to do this," Carson Strong, a professor of human values and ethics at the University of Tennessee

College of Medicine, told the Washington Post in December.

But Siemionow, even though she was not directly challenged on ethical grounds, headed her critics off with a logical speech about the rigor of their bioethical procedures and an emotional appeal to help victims like a young woman whose entire face had been burned off in Afghanistan.

"Why would we transplant the face?" Maria Siemionow asked her colleagues. "Because it's very difficult to go around life having no face."

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