Figure 4:

Mesenteries and peritoneal ligaments build into several larger and less pronounced peritoneal cul de sacs (called fossae, recessus and/or fovea).

(A) Left paraduodenal recessus, located at the duodenojejunal angle where the duodenum is entering again the peritoneal cavity, and subdivided into: a) the superior duodenal fossa, b) the inferior duodenal fossa, c) the retroduodenal fossa and d) the paraduodenal fossa. (B) The sigmoid recessus is found on the outside of the colon sigmoideum, approximately in its middle (arrow). (C) The supravesical fossae are located between the remnants of the urachus and the left or right umbilical artery. (D) The recessus ileocaecalis superior and inferior are located at the junction of the ileum with the caecum.