The<unk>  (also known as Bilio-Pancreatic Diversion with<unk>  or the<unk>  procedure is a weight loss surgery that alters the gastrointestinal tract with two approaches: a restrictive aspect and a malabsorptive aspect.
The restrictive portion of the surgery reduces the stomach along the greater curvature so that the volume is approximately one third to one fifth of the original capacity. The malabsorptive portion of the surgery reroutes a lengthy portion of the small intestine, creating two separate pathways and one common pathway. The shorter of the two pathways, the digestive loop, takes food from the stomach to the large intestine. The much longer pathway, the bilio-pancreatic loop, carries bile from the liver to the common path. The common path, or common channel, is a stretch of small intestine usually 75-150 centimeters long in which the contents of the digestive path mix with the bile from the bilio-pancreatic loop before emptying into the large intestine. The objective of this arrangement is to reduce the amount of time the body has to capture calories from food in the small intestine and to selectively limit the absorption of fat.
Duodenal switch
Pharyngeal pouch 
Branchial pouch
Morison's pouch
Semilunar hiatus
Hiatus 
Transpyloric plane
Branchial arch