'Pill-Cam' Beats X-Ray in Finding Tumors
Camera You Swallow Takes Pictures as It Tumbles Through Intestines
Dec. 3, 2002 (Chicago) -- A pill-sized camera that patients swallow in order to take doctors on a "fantastic voyage" through the small intestine is more accurate at detecting ulcers and tumors than either CT scans or traditional X-ray studies, according to researchers from the Mayo Clinic.
The "pill cam" can identify areas of the small intestine that have a type of blood vessel malformation called arterial vascular malformations, or AVMs. AVMs are a leading cause of serious intestinal bleeding. Amy K. Hara, MD, a diagnostic radiologist at the Mayo Clinic in Scottsdale, Ariz., tells WebMD that by identifying these vascular problems, doctors can repair these areas before the patient has intestinal bleeding. In the past, repairs came after the fact, so patients had to experience dangerous and frightening bleeding episodes.
This is a major breakthrough, says Hedvig Hricak, MD, PhD, chairman, department of radiology at Memorial Sloan-Kettering Cancer Center in New York. "-"Until now we had no effective way to examine this area," says Hricak. Many patients with small bowel disease are subjected to an endless series of less than satisfactory diagnostic tests, she says.. Hricak was not involved in the Mayo study.
The tiny, capsule-sized endoscopy camera received FDA approval in August, and the Mayo Clinic is one of the few centers to have accumulated data on how well it works.
Hara presented results from the first 52 patients who had diagnostic imaging done using camera endoscopy. All the patients were suspected of having a disease of the small intestine such as Crohn's disease or inflammatory bowel disease. The patients had either traditional X-ray studies -- a barium study -- or CT scan before undergoing camera endoscopy. Many of the patients underwent more than one procedure. A barium study involves taking traditional X-rays of the intestines after swallowing a barium contrast material.
In 42 patients, barium studies detected no vascular abnormalities, one ulcer, and no tumors. "In these same 42 patients the camera endoscopy detected 11 vascular abnormalities, nine ulcers, and three tumors," she said. The tiny camera was just as impressive when compared to CT in 23 patients: It detected five vascular abnormalities, seven ulcers, and two tumors while CT found no vascular problems, three ulcers, and one tumor.
"The bottom line is that the camera did better than either barium or CT," said Hara.
But as good as it is, the camera isn't perfect.
One of the problems with the camera is that it only works in an empty intestine. Patients have to fast for eight hours before swallowing the camera pill, and in "some patients that isn't long enough to empty the intestine," she says. Another shortcoming is the lack of control over camera angles and direction. "The camera is literally tumbling through the intestine, so we only get pictures of what it is pointed at," she said.