Brigham and Women's Hospital, in a first-of-its kind medical trial, has performed a weight-loss procedure that does not require any cutting, offering the possibility of a safer, less traumatic operation to help address the nation's obesity epidemic.

It is particularly promising for the heaviest patients - those who may have hundreds of pounds to lose - for whom traditional surgery is especially risky, said Dr. Christopher Thompson, director of bariatric endoscopy at Brigham and a principal researcher in a 20-patient clinical trial that is just getting underway.

More than 200,000 Americans underwent some kind of obesity surgery last year, according to the American Society for Metabolic & Bariatric Surgery, which estimates that about 15 million Americans are overweight enough to be eligible for the procedure.

In this new, experimental method, which the Brigham carried out last week for the first time, doctors pass a tube into the patient's mouth and down the throat, and then use a tiny needle to sew a series of pleats in the stomach. The pleats narrow the stomach, making it unable to accept a lot of food.

By going down the throat - instead of cutting into a patient's abdomen - doctors are hoping to avoid many of the risks of tradi tional surgery: infections, bleeding, and scarring.

"This is less invasive, and patients would have a very quick recovery, potentially with no postprocedure abdominal pain," Thompson said.

"Patients could be home within a couple hours of this procedure, instead of spending at least a night in the hospital," Thompson said.

The idea of entering a patient's body through an orifice, such as the mouth, is not new.

The same type of scarless surgery has been used on at least 60 other patients nationwide, including one at Baystate Medical Center in Springfield who had a pancreatic lesion treated, and a patient in Chicago who had his gallbladder removed through his mouth.

But the trial at the Brigham and Cleveland Clinic marks the first time American doctors have used this type of procedure for weight loss, Thompson said.

"This may broaden the overall appeal for patients and hospitals to offer this technology," said Dr. Philip Schauer, the project's lead researcher at the Cleveland Clinic.

The researchers say it will probably be several years before they know whether this operation is safe or effective enough to offer to the public.

Dr. Scott Shikora, president of the American Society for Metabolic and Bariatric Surgery, said the premise of the operation sounds promising, but there are several hurdles.

"We need to be careful and not jump into this until [doctors] are adequately trained. There is no data out there that tells us how this is going to go," said Shikora, chief of surgery and bariatric surgery at Tufts Medical Center.

"This has the potential to be the next breakthrough, to be the next stage of less invasive surgery," he said. "The concern is that there will be a learning curve with that. There might be some complications."

The new method is based on the work of a Venezuelan doctor who has performed a similar operation on 64 patients and reported promising results after following the group for one year.

The doctors at the Brigham and the Cleveland Clinic modified the method, refined the tools used to perform the delicate operation, received approval from the US Food and Drug Administration to conduct the small trial, and then recruited 20 patients. At the head of the line was Elizabeth Doane, a 43-year-old Brigham nurse who has struggled with her weight all her life.

Since her two-hour operation on June 16, Doane, who weighed 265 pounds, has lost 13 pounds. The 5-feet-6 nurse aims to lose nearly 90 more in the next year.

"I felt great after three days," she said. "I sometimes have to remember to eat now."

Doane, who has spent years taking care of patients recovering from weight-loss surgery, said she saw firsthand many of the complications from the more traditional gastric bypass or lap band operations. That made her shy away from undergoing the surgery. But she jumped at this chance.

"I've tried Weigh****chers, Atkins, South Beach; you name it, I've been there," Doane said. "The hardest part of dieting is the hunger. This takes away the hunger so you can follow a healthy diet."

Researchers say this operation could hold particular hope for patients far heavier than Doane, who are often considered too sick to face the risks posed by traditional weight-loss surgery. They also envision this method as holding promise for those ruled not heavy enough to qualify for the traditional procedure.

Federal regulators impose rules that generally prohibit patients who are less than 100 pounds overweight from undergoing such surgeries.

"If this is something that pans out, and I am not totally sold out on this yet, this may be something to offer people to prevent them from getting morbidly obese," said Thompson. "It's better to prevent the disease rather than treat it when it's out of control."

While there's no track record for the surgery, Thompson points to data the Brigham has been compiling for the past four years from operations to repair traditional gastric bypass complications.

The doctors have been inserting a tube down patients' throats and stitching up torn bypass sites.

"We had no complications in those 400 [repair operations] that required surgery," he said. "That's been very safe."