Would you attach one of these to your belly button

The announcement came during a late-night comedy show, but the actress Demi Moore apparently was not joking recently when she told host David Letterman that part of her health and healing regimen involves attaching leeches to her belly button. Moore, 45, who has starred in such films as "Ghost" and "A Few Good Men," said that during a recent trip to a spa in Austria, she used the blood-sucking worms to detoxify. She called it "leech therapy."

It was just another bizarre turn in the undulating, up-and-down history of the leech. From medieval medical marvel to sheer quackery and back again over the course of a few centuries, the slimy aquatic creature has once more returned to the medical mainstream -- though not in the way Moore described.

Over the past 30 years, leeches have slithered back into operating rooms across the country, where their expertise in stopping blood from clotting helps with skin grafts and during surgery to reattach severed body parts. In fact, in 2004 the federal Food and Drug Administration officially approved the leech as a bona fide medical device. Since then, its presence in hospitals has increased, prompting researchers and doctors to explore new uses.

"It's not uncommon at all to use leeches in surgeries," said Dr. Renata Webber, assistant professor of plastic and reconstructive surgery at Albert Einstein College of Medicine and Montefiore Medical Center in New York. "I use them a few times a year."

Microsurgeons and surgeons who specialize in reattachment have found that leeches are particularly effective in draining excess blood around reattached or transplanted appendages, where the blood flows in well, but not out. The leech has also proven indispensable in maintaining blood flow during hours-long surgeries in which doctors reattach everything from ears to scalps and fingers.

Common or not, the use of leeches in hospitals still comes as a shock to most patients. "People freak out when I tell them I need to use leeches," Webber added. "But then I tell them, 'Either I put this on you, or you lose your thumb or finger,' and they come around pretty quickly."

But it was not always difficult to convince patients of the leech's virtue. From ancient Egypt through medieval Europe and into the late 19th century, leeches were used under the mistaken belief that they could help balance the body's fluids or "evil humors."

For many years, one of the regular services offered at barbershops was bloodletting -- a practice whose bloody bandages are said to have inspired today's red-and-white swirled barber poles. Countless people sat for the procedure, including George Washington; he died soon thereafter.

Still, even after the use of bloodletting as a cure-all was discredited, along with numerous other medieval remedies, physicians continued to seek (and find) new ways of using leeches. Researchers are currently looking closely at the chemical makeup of the leech's saliva to see whether the compounds it contains might be effective in fighting everything from blood clots to angina. One study is examining whether the saliva is effective in combating the inflammation of osteoarthritis in the knee.

"There are always, always new ways for anything in medicine to be used," said Dr. Joseph Upton, professor of surgery at Harvard Medical School, and a pioneer in the use of leeches. "I wouldn't ever rule out anything. With leech saliva, we're talking about the purest anticoagulant there is. Some of its components are very promising medically."

So what about Demi Moore and her special detoxifying leeches?

"I hope Ms. Moore didn't spend too much money on that," said Rudy Rosenberg, co-owner of Leeches USA, the country's largest supplier of medical leeches. "I've never heard of anyone using leeches to detoxify the blood before."

Not in this century, anyway.

With the hoopla that followed Moore's pronouncement, it was not just the doctors who have found legitimate medical uses for leeches who were upset. Spa owners from coast to coast have fielded inquiries from curious customers since her Letterman appearance. But they appear to have been as taken aback by the treatment as everyone else.

"I've never heard of anyone in this field using leeches at all," said Brooke Atkins, a spokeswoman for Ojai Valley Spa, just north of Ventura, Calif. "If someone came to us wanting detoxification, I guess all I'd be able to recommend is our signature treatment, which combines cleansing mud from the Dead Sea, dry heat and inhalation therapy."