Visceral Voyage––

‘Pill Camera’ Surveys Internal Landscape

By Andrew Gorosko

To diagnose digestive disorders, doctors at Danbury Hospital are now using a miniature camera, which is swallowed by patients, to provide a view of the small intestine, an area that formerly had been difficult to probe for problems.

“It’s just like magic,” said hospital gastroenterologist Donald Gordon, MD, as he intently watched a vivid pulsing image of the small intestine on a computer monitor in a darkened room. The monitor displayed graphic, visceral interior views of the small bowel, which formerly was largely inaccessible to doctors’ diagnostic inspection.

Using an electronic imaging that which is a little bigger than a large vitamin pill, the hospital now employs “capsule endoscopy” for some of its gastrointestinal diagnoses.

“The small bowel has been [a visual] no-man’s land for gastroenterologists,” Dr Gordon said. The tubular small bowel, which is finely folded over upon itself, is approximately 30 feet long and is between 1 inches and 1½ inches in diameter. In the gastrointestinal tract, the small bowel routes food under digestion from the stomach to the large bowel.

After a patient swallows the imaging probe, or “pill camera” as it is known, the electronic device slowly tumbles through the small intestine. The device’s travel is powered by the digestive action known as peristalsis, involving the digestive tract’s wavelike alternating muscular contractions and dilations. During the course of its visceral journey, the pill camera, which contains a set of tiny flashing lights to illuminate its exposures, records a still image twice each second through a transparent section of the capsule.

A capsule endoscopy generates more than 50,000 images of the small bowel. During the test, the pill camera relays data to eight sensors affixed to a patient’s abdomen. That electronic information is collected on a portable data recorder that is worn by the patient.

Doctors later download that data to a computer workstation. The magnified images are then shown at an accelerated playback speed, creating the illusion of a motion. The increased playback speed also reduces the time required to view the complete capsule endoscopy.

Besides providing thousands of color images on the physical condition of the small bowel, the capsule endoscopy system accurately records the locations of medical problems, in the event that surgery is needed, Dr Gordon explained.

Before capsule endoscopy became available, the small bowel posed diagnostic difficulties, Dr Gordon said. Barium-aided studies of that area had only yielded about four percent of the information that is now gathered by a capsule endoscopy, he noted.

Use of the pill camera allows gastroenterologists to inspect about 85 percent of the small intestine. The camera within the capsule has a very wide field of view.

Although the pill camera is not steerable, a maneuverable version of the device is being developed, Dr Gordon said.

In reviewing the results of a capsule endoscopy, doctors are able to check fine physical detail within the small intestine, Dr Gordon said. “We find lesions which are a few millimeters in size,” he said.

Danbury Hospital is one of the first hospitals in the state to use capsule endoscopy equipment. About 100 patients have undergone the diagnostic test at Danbury Hospital, Dr Gordon said.

Compared to previous diagnostic methods, capsule endoscopy equipment has given doctors a diagnostic advantage in about 80 percent of the patients who are tested, he said. The technique has proved especially useful in diagnosing cancer of the small bowel, Dr Gordon said.

Testing Procedure

Under the testing procedure, a patient arrives at the hospital at 7 am, is fitted with the testing gear, and then goes about his or her business during the day, while the pill camera is traveling through the body. The patient returns to the hospital at 3:30 pm. The test data, which had been collected during the day on the patient’s data recorder, is then downloaded onto a computer. Doctors then view the images collected on computer monitors in diagnosing problems of the small bowel. The one-use pill camera passes out of a patient in a bowel movement.

Capsule endoscopy does not replace colonoscopy, which diagnoses problems of the colon. Nor does it replace upper endoscopy, which diagnoses problems of the esophagus and stomach, Dr Gordon said.

Capsule endoscopy gives gastroeneterologists a valuable tool in diagnosing problems of the small intestine, which until now has been a difficult place to check for problems, he said. It has allowed doctors to find tumors during the early-growth stages, he said.

At Danbury Hospital, capsule endoscopy is used in testing for unknown sources of bleeding, unexplained iron-deficiency anemia, malignancies, and for certain types of abdominal pain, Dr Gordon said. Medical insurance companies generally will cover capsule endoscopies, he said.

Given Imaging Ltd, the firm that produces the capsule endoscopy equipment, says that more than 65,000 patients worldwide have had the diagnostic procedure.

Danbury Hospital obtained capsule endoscopy equipment through a gift from hospital donors Dr Peter Buck and his late wife Carmen.