In what could be a first for weight-loss surgery in the United States, surgeons have removed 80 percent of a stomach through a patient's mouth. Previously, surgeons performing stomach-reduction surgery had to make a large incision in the abdomen to remove the excess stomach.

This surgery was performed on Aug. 3 at the University of California, San Diego Medical Center, according to spokeswoman Jacqueline Carr. The patient has since been discharged and is doing well, Carr said in an e-mail.

With their stomachs reduced to 20 percent of their original volume, patients feel full more quickly and eat fewer calories. As a result, patients lose weight – two to four pounds (.9 to 1.8 kilograms) per week after surgery, according to the researchers.

The most common weight-loss surgery in the U.S. is gastric bypass, which, like this new procedure, alters the anatomy of the digestive system to limit how much food can be eaten or digested, according to the Mayo Clinic.

Although the procedures are growing, not everyone qualifies. Federal guidelines limit bariatric surgery to men who are 100 or more pounds overweight and women who are 80 or more pounds overweight and have unsuccessfully attempted to lose weight through other means.

And it is not without risk. A 2006 study found that 18.2 percent of patients returned to the hospital with some kind of post-operative complication within the six months after their weight-loss surgery. Overall complication rates were much higher than 18.2 percent. 

In this through-the-mouth procedure, a type of sleeve gastrectomy, surgeons make five small incisions in the abdomen in order to partially remove and close the stomach. The doctors inserted small instruments, including cameras and staples, through the incisions to close off the stomach. The excess stomach was removed through the patient's mouth. The entire procedure lasted one hour.

"By removing 80 percent of the stomach through the mouth, we minimize trauma to the abdomen," said Santiago Horgan, chief of the minimally invasive surgery and director for the UCSD Center for the Treatment of Obesity. "The absence of a large open incision reduced the risk of a hernia and greatly diminished pain for the patient. We are getting closer to weight-loss surgery with no scars."

The options for less-invasive weight-loss surgery are expanding, according to Horgan, who is also the director of the Center for the Future of Surgery.

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