By Hannah Clark, Body1 Correspondent
December 12, 2001For years, surgeons have relied on "scopes" - long medical tubes inserted through the mouth or anus - to diagnose medical conditions in patient's intestines. At the end of the tube is a camera, which is used to take pictures of the gastrointestinal tract (GI tract) to determine the cause of discomfort.
Until recently, these techniques were the only options for viewing the lining of a patient's GI tract. In August, however, the FDA approved a product that will likely revolutionize the way doctors diagnose patients with diarrhea, abdominal pain, or other intestinal ailments.
The new product -- a camera in a pill-shaped capsule - was developed by Given Imaging, an Israel-based diagnostics company. The concept is simple. A patient swallows the pill in the morning, and continues with their daily routine. The pill moves through the intestinal tract, taking thousands of pictures, which are then transmitted to a small receiving device located on the patient's belt. Eight hours after swallowing the pill, the patient returns the receiving device to the hospital, where the pictures are downloaded and examined. The capsule is excreted naturally.
According to Dr. Badar Anwer, a gastroentologist at Celebration Health in Florida, who has used the imaging capsule to examine three patients since the end of October, the pill provides a lot of advantages over other diagnostic techniques.
Traditional procedures, such as endoscopy and colonoscopy, can take several hours when you consider the additional time needed for pre-procedure sedation and post-procedure.
Another alternative is the small bowel series. In this procedure, the patient drinks a barium contrast medium and the doctor takes x-rays to analyze how the barium flows through the small intestines. While this is useful for detecting large obstructions, the doctor can't directly visualize the bowel, and smaller irritations may be missed. Furthermore, most traditional scopes are not long enough to view the entire small intestine.
Similarly, "push" enteroscopy, illuminates up to one third of the small intestine. In an August 2001 study conducted by Given Imaging, "push" enteroscopy detected a lesion in 50 percent of the cases. The same study showed the imaging pill to be successful 86 percent of the time.
By contrast, the gastrointestinal imaging pill enables the doctor to see photographs of much of the entire small intestine. Better yet, the procedure is convenient for patients, who only have to take the pill and hand over the receiver at the end of the day. No patients or test subjects have reported any discomfort as the pill traveled through the digestive tract.
The pill does have some drawbacks. The physician has no control over the camera, so if a section of intestines are missed, there is no way to direct the camera to take another look. The camera can also potentially get caught on a large tumor or trapped in an intestinal "pocket" if the patient has a condition called diverticulosis of the colon. However, Dr. Anwer emphasized that the pill is large enough to minimize these risks.
In two of his patients, the imaging capsule detected irritations in the small bowel. The third patient's imaging capsule yielded normal (negative) results, but Anwer said that that information is useful, too. "We don't want to leave any stone unturned," said Anwer , "A negative exam is also helpful," in that is rules out numerous possibilities.
In the future, the public can expect new developments in imaging technology.
"There are at least three labs in the world where people are working on this [new technology], " said Anwer.
Researchers hope to expand the use of the capsule, as well as refine it, to enable physicians to have more control over what is visualized.