US Patent 8425451 Gastrointestinal anchor compliance

A collapsible gastrointestinal anchor can be characterized in various embodiments by a radial force of about 0.1 Newtons (N) or greater at a compressed diameter of 25 millimeters (mm); by an average spring rate of about 13 Newtons/meter (N/m) or greater in a range of motion between a relaxed diameter and a compressive elastic deformation diameter; or by a radial force over the range of motion of about 0.1 N or greater. Typically, the anchor can be adapted to be retained within a subject's intestine, more typically in the duodenum, or particularly in the duodenal bulb just distal to the pylorus.