The US military has awarded Boston’s Brigham and Women’s Hospital a multimillion-dollar contract to pay for the face transplants of veterans who have survived catastrophic war injuries in Iraq and Afghanistan. The Department of Defense is hoping they will be able to complete face transplants on six to eight patients over the next 18 months, which would nearly double the nine known procedures completed worldwide.

In April, the facility performed its first face transplant, which was the second done in this country. The $3.4 million award, which also will be used to provide the surgery to civilians, is a signal that face transplantation could be poised to move into mainstream medicine four years after the first such operation, on a French woman, was met with fierce ethical objections

Doctors and military officials said they are unsure how many veterans will qualify but estimate the number could be as high as 200. Patients must be missing at least 25 percent of their faces and cannot be significantly helped by conventional plastic surgery, among other criteria.

“All you have to do is walk through the wards here and you’d find patients you’d consider,” said Dr. Barry Martin, chief of plastic surgery at Walter Reed Army Medical Center in Washington. “We’re left dealing with some pretty horrific injuries on patients who are going to live.”

Because of improved body armor and trauma care on the battlefield, more injured soldiers are surviving. There are nine wounded veterans for every fatality in Iraq and Afghanistan, compared with three wounded for every death in prior conflicts, said Dr. Joseph Rosen, a plastic surgeon at Dartmouth-Hitchcock Medical Center in New Hampshire. But with the growing number of wounded veterans have come more severe injuries that the military is struggling to treat.

Many of the veterans with damage to their faces were injured by improvised explosive devices (IEDs). Although some have other injuries such as brain damage and missing limbs that limit their ability to work, others return to military jobs, living on or near bases. As is the case with civilians who have lost portions of their faces to burns, disease, or traumatic injury, some of these veterans struggle with going out in public, relationships and work.

“We certainly expect that by providing a new face, that would be a big step toward them leading more useful and productive lives,” said Rosen, who is a consultant to Walter Reed and will help the military monitor its contract with Brigham. “It’s very important to address these new problems and come up with viable solutions. It’s not enough just to keep soldiers alive.”

The Brigham contract, along with a smaller award given to the University of Pittsburgh for facial reconstruction surgery, is the first money given out under a Defense Department initiative begun earlier this year to quickly move innovative medical procedures into mainstream practice. The military received 24 proposals, but funded just two.

“We feel [face transplants] are mature enough that with a little more funding we can push this into clinical practice within 18 months,” said Terry Rauch, director of defense medical research and development for the Defense Department.

The contract with the military requires the hospital to measure results, including assessing whether the transplants improve patients’ lives and enable them to return to work. The military is also interested in studying and improving the use of immunosuppressant drugs, which patients must take following a transplant to prevent rejection of the donor tissue. Since most veterans are young, they would have to stay on the drugs, and cope with the side effects, potentially for decades.

“We really want to help them,” said Dr. Bohdan Pomahac, who leads the Brigham face transplant team. “They have given up their faces for our country.”