ELECTRONIC STOOL (E-STOOL): A NOVEL SELF-STABILIZING VIDEO CAPSULE ENDOSCOPE FOR RELIABLE NON-INVASIVE COLONIC IMAGING

摘要

Video capsule endoscopy (VCE) has become a popular non-invasive technique to study the small intestine. However, colonic VCE has been problematic due to capsule tumbling in the larger lumen of this organ. Self-stabilizing VCE is a novel method to visualize the colon without tumbling utilizing a biomimetic approach. The proposed design uses the free energy of the body's natural processes employed to move chyme, and imitates the formation and propagation of stool. In its final stage, it physically and mechanically mimics natural feces. The process starts by administering the capsule orally. The capsule size, shape, and material were chosen to provide a smooth transit throughout the gastrointestinal (GI) tract. Once it reaches the colon, its special outer casing enzymatically dissolves. A stabilizing component that is attached to the back end of the capsule starts quickly expanding in the cecum by osmosis. This increase of the volumetric size of the expandable component (stabilizing component) invokes natural peristalsis by colonic mass reflex. Since the expansion process takes place very quickly, the capsule gets stabilized before the expansion-provoked peristalsis starts. At the final stage, the artificially created expanded component (behaving like an artificial stool) centralizes the capsule during its voyage in the colon, allowing a very smooth transit due to its viscosity. The aim of the present study is to present the design of the capsule from a biomimetic perspective and to comparatively quantify the mechanical properties of the design with those of actual human stool.