Lesser sac

Last updated
Lesser sac
Gray1035.png
The lesser sac (omental bursa) shown in blue, and the greater sac (general cavity) shown in red
Details
Identifiers
Latin bursa omentalis
TA98 A10.1.02.402
TA2 3703
FMA 19800
Anatomical terminology

The lesser sac, also known as the omental bursa, is a part of the peritoneal cavity that is formed by the lesser and greater omentum. Usually found in mammals, it is connected with the greater sac via the omental foramen or Foramen of Winslow. In mammals, it is common for the lesser sac to contain considerable amounts of fat.

Contents

Anatomic margins

Anterior margin
listed from the top-to-bottom margin: Caudate lobe of the liver, lesser omentum, stomach, gastrocolic ligament
Lateral margin
listed from the most anterior to the most posterior margin: Gastrosplenic ligament, spleen, Lienorenal ligament
Posterior margin
Left kidney and adrenal gland, pancreas
Inferior margin
Greater omentum
Superior margin
Liver [1]

If any of the marginal structures rupture their contents could leak into the lesser sac. If the stomach were to rupture on its anterior side though the leak would collect in the greater sac.[ citation needed ]

The lesser sac is formed during embryogenesis from an infolding of the greater omentum. The open end of the infolding, known as the omental foramen is usually close to the stomach.[ citation needed ]

Additional images

See also

Related Research Articles

<span class="mw-page-title-main">Peritoneum</span> Serous membrane that forms lining of abdominal cavity or coelom

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.

<span class="mw-page-title-main">Abdominal cavity</span> Body cavity in the abdominal area

The abdominal cavity is a large body cavity in humans and many other animals that contains many 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.

<span class="mw-page-title-main">Duodenum</span> First section of the small intestine

The duodenum is the first section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In mammals it may be the principal site for iron absorption. The duodenum precedes the jejunum and ileum and is the shortest part of the small intestine.

Articles related to anatomy include:

In anatomy and osteology, a foramen is an open hole that is present in extant or extinct amniotes. Foramina inside the body of animals typically allow nerves, arteries, veins, or other structures to connect one part of the body with another.

<span class="mw-page-title-main">Mesentery</span> Contiguous fold of tissues that supports the intestines

The mesentery is an organ that attaches the intestines to the posterior abdominal wall and is formed by the double fold of peritoneum. It helps in storing fat and allowing blood vessels, lymphatics, and nerves to supply the intestines, among other functions.

<span class="mw-page-title-main">Lesser omentum</span>

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.

<span class="mw-page-title-main">Shoulder joint</span> Synovial ball and socket joint in the shoulder

The shoulder joint is structurally classified as a synovial ball-and-socket joint and functionally as a diarthrosis and multiaxial joint. It involves an articulation between the glenoid fossa of the scapula and the head of the humerus. Due to the very loose joint capsule that gives a limited interface of the humerus and scapula, it is the most mobile joint of the human body.

<span class="mw-page-title-main">Greater sac</span>

In human anatomy, the greater sac, also known as the general cavity (of the abdomen) or peritoneum of the peritoneal cavity proper, is the cavity in the abdomen that is inside the peritoneum but outside the lesser sac.

<span class="mw-page-title-main">Foregut</span> Anterior part of the gastrointestinal tract

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.

<span class="mw-page-title-main">Greater omentum</span> Fat sheath under abdominal wall

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.

<span class="mw-page-title-main">Gastrocolic ligament</span>

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.

<span class="mw-page-title-main">Hepatoduodenal ligament</span>

The hepatoduodenal ligament is the portion of the lesser omentum extending between the porta hepatis of the liver and the superior part of the duodenum.

<span class="mw-page-title-main">Coronary ligament</span>

The coronary ligament of the liver refers to parts of the peritoneal reflections that hold the liver to the inferior surface of the diaphragm.

<span class="mw-page-title-main">Curvatures of the stomach</span> Anatomy of the human stomach

The curvatures of the stomach refer to the greater and lesser curvatures. The greater curvature of the stomach is four or five times as long as the lesser curvature.

<span class="mw-page-title-main">Portal venous system</span> The capillary bed pools into another through veins without first going through the heart

In the circulatory system of vertebrates, a portal venous system occurs when a capillary bed pools into another capillary bed through veins, without first going through the heart. Both capillary beds and the blood vessels that connect them are considered part of the portal venous system.

The hepatorenal ligament is the fold of peritoneum that extends from the lower posterior surface of the liver to the anterior surface of the right kidney. It forms the right margin of the lesser sac.

<span class="mw-page-title-main">Outline of human anatomy</span> Overview of and topical guide to human anatomy

The following outline is provided as an overview of and topical guide to human anatomy:

<span class="mw-page-title-main">Omental foramen</span> Part of the human abdomen

In human anatomy, the omental foramen, is the passage of communication, or foramen, between the greater sac, and the lesser sac.

The development of the digestive system in the human embryo concerns the epithelium of the digestive system and the parenchyma of its derivatives, which originate from the endoderm. Connective tissue, muscular components, and peritoneal components originate in the mesoderm. Different regions of the gut tube such as the esophagus, stomach, duodenum, etc. are specified by a retinoic acid gradient that causes transcription factors unique to each region to be expressed. Differentiation of the gut and its derivatives depends upon reciprocal interactions between the gut endoderm and its surrounding mesoderm. Hox genes in the mesoderm are induced by a Hedgehog signaling pathway secreted by gut endoderm and regulate the craniocaudal organization of the gut and its derivatives. The gut system extends from the oropharyngeal membrane to the cloacal membrane and is divided into the foregut, midgut, and hindgut.

References

  1. Shahani RB, Bijlani RS, Dalvi AN, Shah HK, Samsi AB (1994). "Massive upper gastrointestinal haemorrhage due to direct visceral erosion of splenic artery aneurysm". J Postgrad Med. 40 (4): 220–222. PMID   9136245.