Anatomy of the Stomach and Abdominal Regions

Stomach

• The stomach is the most dilated part of the gastrointestinal tract, located between T11 and L1.
• It's shaped like a J.
• Its capacity ranges from 1 to 1.5 liters, with a volume of 30 to 50 cubic centimeters.
• The stomach measures approximately 11 by 25 cm.

Abdominal Regions

• The abdominal cavity is divided into 9 regions by two vertical and two horizontal lines.
• Regions include: right hypochondrium, epigastric region, left hypochondrium, right flank, umbilical region, left flank, right groin, pubic region, and left groin.

Stomach Regions

• Fundus: The part closest to the diaphragm.
• Corpus (Body): The main central part..
• Pyloric: The part connecting to the duodenum, which includes the pyloric antrum and canal.
• Cardia: The part near the esophagus.
• Lesser curvature: The inner curve of the stomach
• Greater curvature: The outer curve of the stomach
• Angular incisure: The angle between the lesser and greater curvatures.

Stomach Layers and Histology

• The stomach has a mucosal layer (inner lining).
• The stomach also contains a submucosal layer.
• The stomach's muscular layer is composed of longitudinal, circular, and oblique muscle layers.
• The stomach's outer layer is the peritoneal layer.

Stomach Blood Supply

• The blood supply to the stomach comes from the celiac trunk, which branches into the left gastric, splenic, and common hepatic arteries.
• The various arteries of the stomach include short gastric, left and right gastroepiploic, and supraduodenal arteries.

Stomach Lymph Nodes

• Lymphatic drainage from the stomach occurs via the celiac, gastric, and superior and inferior mesenteric lymph nodes.

Stomach Nerves

• The stomach is innervated by anterior and posterior vagal trunks.
• Branches of the vagus nerve also supply the stomach.

Duodenum

• The duodenum is the first part of the small intestine.
• Its shape is C-shaped.
• It is located adjacent to the head of the pancreas.
• The duodenum is approximately 25 cm long.
• It has four parts: superior, descending, horizontal, and ascending.
• A variety of arteries and veins supply the duodenum.
• Lymphatic and nerve supply are significant parts of this structure.

Stomach and Duodenum Differences

• The primary difference between the stomach and duodenum is their location and function.
• The stomach breaks down food into a chyme form.
• The duodenum continues the digestive process using secretions from the pancreas and liver.

Histology of the Duodenal Wall

• The duodenal wall consists of layers including mucosa, submucosa, muscularis, and serosa.
• Characteristic cells, glands, and specializations present in this section are integral to functions.