Peritoneal cavity

The space between the parietal and visceral layers of the peritoneum is named the peritoneal cavity; but under normal conditions this cavity is merely a potential one, since the parietal and visceral layers are in contact. The peritoneal cavity gives off a large diverticulum, the omental bursa, which is situated behind the stomach and adjoining structures; the neck of communication between the cavity and the bursa is termed theepiploic foramen (foramen of Winslow). Formerly the main portion of the cavity was described as the greater, and the omental bursa as the lesser sac. The peritoneal cavity is a potential space between the parietal peritoneum and visceral peritoneum, that is, the two membranes that separate the organs in the abdominal cavity from the abdominal wall.