The peritoneum

The peritoneum is a remarkably simple yet complex organ. Its choreographed folds and reflections resulting in ligaments, mesenteries, omenta, and cavities house and sustain the many vital organs and structures of the abdomen and pelvis. However, abnormal pathologic processes can also usurp the building blocks of the peritoneum. For example, the peritoneum can be thickened due to metastasis, primary peritoneal tumors, infection, and inflammation. Solid and cystic masses invading and distorting the omenta and mesenteries can be due to a variety of causes, such as omental infarction, carcinoid, desmoid, lymphoma, and metastasis. Abnormal peritoneal fluid collections such as ascites and mucin, furthermore, can distend the peritoneal cavity. Calcifications, intraperitoneal air, peritoneal defects, and foreign bodies are other abnormalities that claim the peritoneum.