Swallowable camera tours digestive tract

Regular use is a way off, but the tiny device may take the place of more painful probes.

©Associated Press, published May 25, 2000

[AP] Digestive tract contractions propel the camera through the body.

Scientists have developed a medical exam that sounds like something out of the sci-fi movie Fantastic Voyage: The patient swallows a tiny camera that yields a living-color tour of the digestive tract as it passes painlessly through the body.

The inventors of the camera-in-a-capsule hope it will someday replace colonoscopies and other uncomfortable and even painful diagnostic exams in which a flexible fiber-optic tube is inserted in the rectum or down the throat.

"The capsule transmits images painlessly from areas we've never been able to see before," said British gastroenterologist Paul Swain of the Royal London Hospital, who directed the tests. "With endoscopy, you have to push wires and cables inside the patients, and it actually hurts."

Other researchers agreed that wireless technology will be the next leap in medical imaging and diagnostics.

But they said the capsule, at least in its current form, is too limited to replace endoscopes, as the fiber-optic tubes are called.

It could be several years before the camera wins approval. The developers plan the first human trials in the United States later this year.

"It's on the cutting edge. It's fascinating," said Col. Peter McNally, who is at Evans Army Community Hospital at Fort Carson, Colo., and is medical spokesman for the American College of Gastroenterology. "But you don't have the flexibility with this camera to look around or go back.

"It's just whipping by."

The digestive tract is a 30-foot network of organs that follows a coiled route through the body. Endoscopes can view much of the system down through the throat and up through the colon.

Endoscopy has become a routine hospital procedure to diagnose and treat many digestive ailments, including colorectal cancer, the second-leading cancer killer in the United States with more than 56,000 deaths in 1999.

In March, Today show host Katie Couric invited millions of viewers to share in her colonoscopy. After she drank a purgative, doctors snaked a fiber-optic camera into a sedated and woozy Couric, examining several feet of her large intestine for pre-cancerous growths.

However, remote portions of the small intestine are difficult to examine without very long and uncomfortable equipment or exploratory surgery.

That inspired the capsule's development by Swain and Given Imaging, an Israeli company.

The initial test results were published today in the journal Nature. Ten healthy volunteers swallowed the high-tech capsules, which are slightly larger than an antibiotic and covered with a non-digestible coating.

One end of the capsule is fitted with a window for a light and a camera with a fixed, wide-angle lens. Both are powered by a tiny battery. A transmitter sends digital images to a belt-mounted receiver worn by the patient.

Apart from not eating before the exam, the patient can follow an everyday schedule while the digestive tract's natural contractions sweep the capsule on through within six hours.

The capsule is not retrieved.

Afterward, the doctor downloads the images from the receiver and views them on a computer screen.

"We're looking for pathologies -- abnormal blood vessels, small bowel tumors, ulcers, lymphomas, abnormalities of the mucous lining," said Swain, who also swallowed a capsule and viewed his own digestive tour.

"The images were pretty good," he said.

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