Researchers from the Royal London Hospital in London, England, assessed the use of wireless capsule endoscopy in two clinical studies.
They reported their findings to the Annual Meeting of the British Society of Gastroenterology, held in Birmingham, England.
In the first study, 38 volunteers and patients referred with obscure gastrointestinal bleeding were included. Colonic views were obtained during clinical studies of capsules with a 7.5-hour life.
From the studies performed, interpretable images of the human colon were acquired in 35, mucosal detail was seen in 34, fecal material in 35, and there was underillumination in 10.
Technical improvements included shorter capsules (27mm, previously 33mm), transmitting for 7-8 hours using 2 (previously 3) batteries. Experimental capsules with a 12-hour life were also tested.
Clinical studies in 13 patients revealed missed colon cancer/polyp (3), bleeding Meckel's diverticulum (1), ulcerative colitis (2), and angiodysplasia (2).
The team found that capsules used in patients with incomplete colonoscopies provided useful clinical information. Management was altered in 50% of patients who underwent capsule colonoscopy.
Author M. Mylonaki and colleagues commented that wireless capsule colonoscopy is feasible and has already delivered valuable information in clinical studies.
"Technical development, and better preparation and control over colonic motility are required to extend the range and improve the images of the colon in patients", they said.
"Capsule colonoscopy was a useful adjunct to conventional colonoscopy, especially in patients with difficult recurrent bleeding or incomplete colonoscopy," they concluded.
In the second study, clinical efficacy and technical performance of wireless capsule endoscopy was assessed in a series of 55 patients.
In a subset of 38 patients, push-enteroscopy was compared with capsule endoscopy.
| All patients preferred capsule endoscopy to push-enteroscopy.
A bleeding source was discovered in the small intestine in 21 of 38 patients (55%). These included angiodysplasia (11), fresh blood (5), ileal ulcer (1), tumor (2), Meckel's diverticulum (1), and vasculitis (1).
The researchers observed active intestinal bleeding in 3 patients.
No additional intestinal diagnoses were made by enteroscopy.
The yield of push-enteroscopy in evaluating obscure bleeding was 30%.
The capsule found significantly more intestinal bleeding abnormalities than push-enteroscopy. A source of bleeding was identified beyond the reach of the push enteroscope in 9/21 (42%).
Therapy was altered in 50% of patients. In 3 patients, who had required more than 100 units of blood, directed surgery cured (2) or markedly reduced (1) the bleeding.
Furthermore, it was found that patients always preferred capsule endoscopy to push-enteroscopy, and there were no complications.
The team commented that the study showed that capsule endoscopy provides small intestinal imaging comparable to push-enteroscopy and can diagnose intestinal bleeding at sites beyond the reach of push-enteroscopes.
They concluded that the procedure was safe and well tolerated.