A technical review and clinical assessment of the wireless motility capsule

The wireless motility/pH capsule (WMC) is an orally ingested, nondigestible, data recording device that enables the simultaneous assessment of regional and whole gut transit. Approved by the US Food and Drug Administration for the evaluation of patients with suspected delayed gastric emptying and the evaluation of colonic transit time in patients with chronic idiopathic constipation, this capsule continuously measures the temperature, pH, and pressure of its surrounding environment while traveling through the gastrointestinal tract (via gut peristalsis) until exiting the body through the anus. Validated patterns in pH and temperature recordings allow for accurate measurement of gastric emptying, small bowel transit, colonic transit, and whole gut transit times. The WMC is a nonradioactive, office-based, gastrointestinal transit testing modality shown in several clinical trials to be a suitable alternative to scintigraphy and radiopaque marker studies in measuring gastric emptying, small bowel, colonic, and whole gut transit times. Unlike widely available transit tests, which provide only region-specific transit data, the WMC offers the benefit of measuring gastric, small bowel, and colonic transit times in a single examination. The WMC also provides intraluminal pressure readings throughout the digestive tract, offering a noninvasive means by which to assess gastrointestinal motility. The WMC should be considered the transit study of choice for individuals suspected of having altered transit in more than one region of the gastrointestinal tract. This review summarizes the features and performance characteristics of the WMC as well as provides a summary on how this diagnostic modality is most effectively used in the assessment of gastrointestinal symptom complexes due to suspected abnormalities in transit.