BY DR NOMAN ULLAH WAZIR

BY DR NOMAN ULLAH WAZIR

The stomach (from ancient Greek word stomachos, stoma means mouth) is a muscular, hollow and the most dilated part of the GIT. It starts from the point where esophagus ends. It ends at the beginning of the small intestine. STOMACH

It lies in the epigastric, umbilical regions, and left hypochondrium of the abdomen. STOMACH

PARTS OF STOMACH The stomach is divided into four regions: Cardia: surrounding area of the esophageal (cardiac) sphincter. Fundus: area above the level of the esophageal opening. Body of stomach: largest region of the stomach. Pyloric part: divided into the pyloric antrum and the pyloric canal and is the distil end of the stomach.

SHAPE OF STOMACH The shape and position of the stomach depends upon the changes within itself and in the surrounding viscera. Main factors influencing the shape and position of stomach are : (1) The amount of the stomach contents (2) The stage which the digestive process has reached, (3) The degree of development of the gastric musculature, and (4) The condition of the adjacent intestines. (5) pregnancy

THE STOMACH PRESENTS Two openings Two borders or curvatures Two surfaces.

cardiac orifice: It is situated on the left of the middle line at the level of the tenth thoracic vertebra. The short abdominal portion of the esophagus is conical in shape and curved sharply to the left, the base of the cone being continuous with the cardiac orifice of the stomach. OPENINGS

Pyloric orifice lies to the right of the middle line at the level of the upper border of the first lumbar vertebra. communicates with the duodenum, and its position is usually indicated on the surface of the stomach by a circular groove, the duodenopyloric constriction (pyloric sphincter).

The lesser curvature: extending between the cardiac and pyloric orifices. It forms the right or posterior border of the stomach. It descends as a continuation of the right margin of the esophagus and crosses the first lumbar vertebra and ends at the pylorus. CURVATURES

Nearer its pyloric end is a well-marked notch, the incisura angularis, which varies somewhat in position with the state of distension of the stomach.

GREATER CURVATURE Greater curvature: Forms the longer convex left border of the stomach. Starting from the cardiac orifice at the incisura cardiaca, it forms an arch backward, upward, and to the left; the highest point of the convexity is on a level with the sixth left costal cartilage.

SURFACES Antero-superior Surface The left half of this surface is in contact with the diaphragm, which separates it from the base of the left lung, the pericardium, and the seventh, eighth, and ninth ribs, and intercostal spaces of the left side. The right half is in relation with the left and quadrate lobes of the liver and with the anterior abdominal wall. When the stomach is empty, the transverse colon may lie on the front part of this surface. The whole surface is covered by peritoneum.

Postero-inferior Surface: It is in relation with the diaphragm, the spleen, the left suprarenal gland, the upper part of the front of the left kidney, the anterior surface of the pancreas, the left colic flexure, and the upper layer of the transverse mesocolon. These structures form a shallow bed, the stomach bed.

The stomach bed refers to the structures upon which the stomach rests. STOMACH BED The term was introduced around 1896 by Dr. Ambrose of the Catholic University School of Medicine, Dublin.

CONTENTS OF STOMACH BED Structures forming bed of stomach: Pancreas Spleen left kidney left suprarenal gland transverse mesocolon splenic artery.

INTERIOR OF THE STOMACH The smooth surface of gastric mucosa is radish brown during life, except at the pyloric part, were it is pink. The gastric mucosa is thrown in to longitudinal ridges called gastric folds (gastric rugae). During swallowing a temporary groove like gastric canal forms between the longitudinal gastric folds along the lesser curvature. Gastric canal is formed because of firm attachment of the mucosa to the muscular layer which dose not have the oblique layer.

The arteries supplying the stomach are: BLOOD SUPPLY The left gastric (from celiac trunk) The right gastric (from common hepatic artery) Right gastroepiploic branches of the hepatic left gastroepiploic and short gastric branches of the splenic artery.

VENOUS DRAINAGE The veins veins acompany there coresponding arteries and drains either in the splenic and superior mesenteric veins, or directly in the portal vein.

NERVE SUPPLY Parasympathetic inervation: The nerves are the terminal branches of the right and left vagi. the right vagus being distributed upon the back, and the left vagus upon the front part of the organ.

Sympathetic inervation: The sympathetic nerve supply of the stomach from T6 through T9 segment of spinal cord passes to the celiac pluxes through the greater splanchnic nerve.

LYMPHATIC DRAINAGE The lymphatics are numerous: they consist of a superficial and a deep set, and pass to the lymph glands found along the two curvatures of the organ

LYMPHATIC DRAINAGE The gastric lymphatic vessels travel with the arteries along the greater and lesser curvatures of the stomach. Lymph fluid drains into the gastric and gastroomental lymph nodes found at the curvatures.

Efferent lymphatic vessels from these nodes connect to the coeliac lymph nodes, located on the posterior abdominal wall and into superior mesentric lymph nodes.