DEPARTMENT OF ANATOMY

ABDOMEN

Esophagus

The abdominal oesophagus

• The abdominal oesophagus measures approximately 1.25 cm in length.

• Phrenicoesophageal ligament• Esophagogastric junction: T11 vert,Z-line

Barrett's esophagus

• The normal squamous epithelium lining of the esophagus is replaced by metaplastic columnar epithelium.

Nerves of abdominal esophagus

• The right and left vagus nerves (CN X) divide into branches that form the esophageal plexus around the inferior esophagus.

• Anterior and posterior gastric branches of the plexus accompany the esophagus through the esophageal hiatus for distribution to the anterior and posterior aspects of the stomach.

Esophageal Varices

• The lower third of the oesophagus is a site of porto-systemic venous anastomosis. This is formed between tributaries of the left gastric and azygos veins

Esophagageal varices

Stomach

Stomach• The stomach is the most dilated part of the

gastrointestinal tract and has a J-like shape.• Positioned between the abdominal esophagus and

the small intestine, the stomach is in the epigastric, umbilical, and left hypochondrium regions of the abdomen.

• It stores food (in the adult it has a capacity of about 1500 mL), it mixes the food with gastric secretions to form a semifluid chyme, and it controls the rate of delivery of the chyme to the small intestine so that efficient digestion and absorption can take place.

Surface anatomy of stomach parts

Parts of the Stomach

• Has two openings: Cardiac and pyloric orifices • Two curvatures: Greater and lesser curvatures• Two surfaces: Anterior and a posterior surface

The stomach is divided into four regions

• 1. Cardia• 2. Fundus of stomach• 3. Body of stomach• 4. Pyloric part: which is divided into the

pyloric antrum and pyloric canal and is the distal end of the stomach

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Interior of the Stomach

• When contracted, the gastric mucosa is thrown into longitudinal ridges called gastric folds, or gastric rugae, they are most marked toward the pyloric part and along the greater curvature.

Hiatal Hernia

• 1.Paraesophageal hiatal hernia:the cardia remains in its normal position, however, a pouch of peritoneum, often containing part of the fundus, extends through the esophageal hiatus

• 2.Sliding hiatal hernia:the abdominal part of the esophagus, the cardia, and parts of the fundus of the stomach slide superiorly through the esophageal hiatus into the thorax

Blood supply• The arterial

supply to the stomach is

exclusively from branches of the celiac artery. Venous drainage is to the portal system

Celiac trunk

• The celiac trunk is the anterior branch of the abdominal aorta supplying the foregut.

• It arises from the abdominal aorta immediately below the aortic hiatus of the diaphragm anterior to the upper part of vertebra LI.

• It immediately divides into the left gastric, splenic, and common hepatic arteries.

Veins of stomach and duodenum

• Venous drainage from the stomach and duodenum is into the portal vein, either directly or indirectly via the splenic or superior mesenteric vein (SMV).

• The splenic vein usually receives the inferior mesenteric vein and then unites with the SMV to form the portal vein.

• The right and left gastric veins drain into the portal vein.

• short gastric veins and left gastro-omental veins drain into the splenic vein.

• The right gastro-omental vein empties in the SMV.

Nerve supply• Parasympathetic

• The anterior and posterior vagal trunks arise from the oesophageal plexuses and enter the abdomen through the oesophageal hiatus.

• The hepatic branches of the anterior vagus pass to the liver.

• The coeliac branch of the posterior vagus passes to the coeliac ganglion from where it proceeds to supply the intestine down to the distal transverse colon.

• The anterior and posterior vagal trunks descend along the lesser curve as the anterior and posterior nerves of Latarjet from which terminal branches arise to supply the stomach,

• The sympathetic nerve supply of the stomach from the T5 through T9 segments of the spinal cord passes to the celiac plexus through the greater splanchnic nerve.

Sympathetic

Peptic Ulcer

• A peptic ulcer is a hole in the gut lining of the stomach, duodenum, or esophagus. A peptic ulcer of the stomach is called a gastric ulcer; of the duodenum, a duodenal ulcer; and of the esophagus, an esophageal ulcer.

• An ulcer occurs when the lining of these organs is corroded by the acidic digestive juices which are secreted by the stomach cells.

• >80% involve Helicobacter pylori

Complications of Peptic ulcer

• 1.Gastro intestinal bleeding• 2. Perforation• 3. Cancer• Perforation• Lesser curvature :Erosion of gastric artery (R & L)

• Posterior Surface of stomach: Splenic artery• Posterior wall of 1st part of duodenum: Gastroduodenal artery

Vagotomy(surgical section of the vagus nerves) is performed in some people

with chronic or recurring ulcers to reduce the production of acid

• A truncal vagotomy (surgical section of the vagal trunks) is rarely performed because the innervation of other abdominal structures is also sacrificed

• A selective proximal vagotomy :attempts to denervate even more specifically the area in which the parietal cells are located

Selective vagotomy and truncal vagotomy

Antrectomy and truncal vagotomy for duodenal ulcer with

Billroth I anastomosis.

Gastrectomy

• Total gastrectomy • Partial gastrectomy

Stomach cancer

Partial gastrectomy with gastrojejunostomy (Billroth II)

Total gastrectomy