The peritoneum is the serous membrane forming the lining of the abdominal cavity or coelom in amniotes and some invertebrates, such as annelids. It covers most of the intra-abdominal organs, and is composed of a layer of mesothelium supported by a thin layer of connective tissue. This peritoneal lining of the cavity supports many of the abdominal organs and serves as a conduit for their blood vessels, lymphatic vessels, and nerves.
The abdominal cavity is a large body cavity in humans and many other animals that contain organs. It is a part of the abdominopelvic cavity. It is located below the thoracic cavity, and above the pelvic cavity. Its dome-shaped roof is the thoracic diaphragm, a thin sheet of muscle under the lungs, and its floor is the pelvic inlet, opening into the pelvis.
Peritonitis is inflammation of the localized or generalized peritoneum, the lining of the inner wall of the abdomen and cover of the abdominal organs. Symptoms may include severe pain, swelling of the abdomen, fever, or weight loss. One part or the entire abdomen may be tender. Complications may include shock and acute respiratory distress syndrome.
In human anatomy, the mesentery, an organ that attaches the intestines to the posterior abdominal wall, comprises the double fold of the peritoneum. It helps in storing fat and allowing blood vessels, lymphatics, and nerves to supply the intestines.
The peritoneal cavity is a potential space located between the two layers of the peritoneum—the parietal peritoneum, the serous membrane that lines the abdominal wall, and visceral peritoneum, which surrounds the internal organs. While situated within the abdominal cavity, the term peritoneal cavity specifically refers to the potential space enclosed by these peritoneal membranes. The cavity contains a thin layer of lubricating serous fluid that enables the organs to move smoothly against each other, facilitating the movement and expansion of internal organs during digestion.
In human anatomy, the abdominal aorta is the largest artery in the abdominal cavity. As part of the aorta, it is a direct continuation of the descending aorta.
The lesser omentum is the double layer of peritoneum that extends from the liver to the lesser curvature of the stomach, and to the first part of the duodenum. The lesser omentum is usually divided into these two connecting parts: the hepatogastric ligament, and the hepatoduodenal ligament.
An umbilical hernia is a health condition where the abdominal wall behind the navel is damaged. It may cause the navel to bulge outwards—the bulge consisting of abdominal fat from the greater omentum or occasionally parts of the small intestine. The bulge can often be pressed back through the hole in the abdominal wall, and may "pop out" when coughing or otherwise acting to increase intra-abdominal pressure. Treatment is surgical, and surgery may be performed for cosmetic as well as health-related reasons.
In human anatomy, the transverse colon is the longest and most movable part of the colon.
The foregut in humans is the anterior part of the alimentary canal, from the distal esophagus to the first half of the duodenum, at the entrance of the bile duct. Beyond the stomach, the foregut is attached to the abdominal walls by mesentery. The foregut arises from the endoderm, developing from the folding primitive gut, and is developmentally distinct from the midgut and hindgut. Although the term “foregut” is typically used in reference to the anterior section of the primitive gut, components of the adult gut can also be described with this designation. Pain in the epigastric region, just below the intersection of the ribs, typically refers to structures in the adult foregut.
The greater omentum is a large apron-like fold of visceral peritoneum that hangs down from the stomach. It extends from the greater curvature of the stomach, passing in front of the small intestines and doubles back to ascend to the transverse colon before reaching to the posterior abdominal wall. The greater omentum is larger than the lesser omentum, which hangs down from the liver to the lesser curvature. The common anatomical term "epiploic" derives from "epiploon", from the Greek epipleein, meaning to float or sail on, since the greater omentum appears to float on the surface of the intestines. It is the first structure observed when the abdominal cavity is opened anteriorly.
The gastrocolic ligament is a portion of the greater omentum that stretches from the greater curvature of the stomach to the transverse colon. It forms part of the anterior wall of the lesser sac.
Adhesions are fibrous bands that form between tissues and organs, often as a result of injury during surgery. They may be thought of as internal scar tissue that connects tissues not normally connected.
The hepatogastric ligament or gastrohepatic ligament connects the liver to the lesser curvature of the stomach. It contains the right and the left gastric arteries. In the abdominal cavity, it separates the greater and lesser sacs on the right. It is sometimes cut during surgery in order to access the lesser sac. The hepatogastric ligament consists of a dense cranial portion and the caudal portion termed the pars flaccida.
The gastrosplenic ligament is part of the greater omentum extending between the stomach and the spleen. It contains several blood vessels.
Omental cake is a radiologic sign indicative of an abnormally thickened greater omentum. It refers to infiltration of the normal omental structure by other types of soft-tissue or chronic inflammation resulting in a thickened, or cake-like appearance.
The gastric lymph nodes are lymph nodes which drain the stomach and consist of two sets, superior and inferior:
Omentopexy is a surgical procedure whereby the greater omentum is sutured to a nearby organ. Suture to the abdominal wall is used to induce circulation away from the portal circulation into caval circulation. It may also be sutured to another organ to increase arterial circulation.
In human anatomy, the omental foramen is the passage of communication, or foramen, between the greater sac, and the lesser sac of the peritoneal cavity.
Omental infarction, or omental torsion, is an acute vascular disorder which compromises tissue of the greater omentum—the largest peritoneal fold in the abdomen.
