A tiny ingestible video camera is not only less invasive than conventional tools for diagnosing bowel diseases but has now proven to be vastly more sensitive.
Researcher Amy Hara and colleagues at the Mayo Clinic in Scottsdale, Arizona studied the effectiveness of so-called camera pills, known formally as capsule endoscopy, in an effort to improve the diagnosis of small bowel disease.
Small bowel disease is a condition involving inflammation in the intestines. Symptoms include cramping, diarrhea and the destruction of the bowel wall, which can lead to deep ulcerations and a narrowing of the intestines.
The definitive test for inflammatory bowel disease is a biopsy in which tissue samples are harvested from several areas of the bowel. This is usually done via endoscopy, a procedure in which a tiny tubular instrument with a camera on its end is inserted down the throat and into the small intestine.
This method is invasive and limited because the scope reaches only the upper and very lower portions of the small intestine.
Unlike standard endoscopy, capsule endoscopy can examine the small bowel’s entire length—as long as 25 feet.
For the technique, patients fast for eight hours and then swallow a video camera the size of a large vitamin pill.
The intestine’s involuntary muscles push the capsule forward while the camera transmits a continuous stream of digital images to a data recorder patients wear around their waist. A physician then downloads the data and analyzes the images.
Capsule endoscopy can be used to detect abnormalities while computed tomography, a noninvasive diagnostic imaging technique, can point out their location.
“As the camera tumbles through the intestine, you don’t know exactly where the mass is located,” says Hara. “CT, by contrast, provides a very good global view of the body, and specialized parameters can be employed to localize lesions.”
Among those who may benefit from capsule endoscopy are people with Crohn’s disease, a form of inflammatory bowel disease that occurs most often in the lower portion of the small intestine and is marked by diarrhea, abdominal pain and bleeding.
Thanks to Hara and colleagues, capsule endoscopy may now become more widely used.
The technique has proven to identify more tumors, ulcers, vascular malformations and other small bowel abnormalities than ingested barium exams or computed tomography alone.
To test the use of capsule endoscopy for small bowel disease, Hara and colleagues reviewed data on 52 patients undergoing the procedure following a barium exam or computed tomography.
Of the 40 patients who received a barium exam and capsule endoscopy, the camera pills helped radiologists detect abnormalities in 55% while barium exams yielded abnormal results in only three percent.
Of the 19 patients that underwent a computed tomography exam as well as capsule endoscopy, the camera pills helped radiologists detect abnormalities in 63% while computed tomography yielded abnormal results in 21%.
“We wanted to see what we were missing or not missing with standard radiology techniques,” says Hara. “The information we are gaining from CE will allow us to improve our use of CT for better diagnoses and determine when to pair the two technologies.”