Analysis of Large Bowel Peristalsis with Video Capsule Endoscopy

Irritable bowel syndrome(IBS) is suggested to be diagnosed with evaluating large bowel peristalsis. Video capsule endoscopy(VCE) enables a clinician to observe natural peristalsis of the gastrointestinal tract. In our pilot study, about 80% of PillCamtrade SB(Given Imaging Ltd., Yoqneam, Israel) capsule endoscopes (CEs) which were originally designed for viewing the small intestine reached cecum and transmitted images of large bowel until 8 hours of their battery lifetimes are over. Large bowel peristalsis can be observed as a series of VCE's images by the clinician taking over an hour to analyse. In this paper we present analysing methods of large bowel peristalsis with VCE, which make clinicians be able to diagnose peristaltic activity and patterns at a glance. We count pixels in low brightness areas of each VCE images to analyse peristaltic activity. The low brightness areas which are distant from CE's white-light-LEDs spread with circular muscle layers of large bowel(CM) being relaxed. We estimate peristaltic patterns by the distance between the center of the image and the closest pixel of the low brightness areas. Normal peristalsis caused by normal contraction of CM make the CE point towards longitudinal direction of the intestinal tract. By applying these methods to both a control group of 9 healthy volunteers(GOH) and a group of 5 IBS patients(GOI), we present experimental results that demonstrate the effectiveness of these methods.