Anatomy of the Stomach PDF

Module Name: NUTRITION module Anatomy Department Prof. Dr. Eman Badawi Elshal Former Vice Dean of Education &Student Affairs external reviewer at the National Authority for Quality Assurance and Accreditation of Education “NAQA...

Module Name: NUTRITION module Anatomy Department Prof. Dr. Eman Badawi Elshal Former Vice Dean of Education &Student Affairs external reviewer at the National Authority for Quality Assurance and Accreditation of Education “NAQAAE” Professional Diploma of Medical Education (PDME) Certified Assessor in Health Professions Education from Middle East North Africa FAIMER Official e-mail: [email protected] Mobile number: 01092889189 Prof.Dr.EMAN BADAWI ELSHAL  OBJECTIVES At the end of this lecture the student able to: 1. Describe the site, shape and parts ,ends of the stomach (cardiac and pyloric end). 2. Define the parts and relations of the stomach. 3. Explain the blood and nerve supply and lymphatic drainage of the stomach. Prof.Dr.EMAN BADAWI ELSHAL Abdominal Regions Subdivision of the abdominal cavity The abdominal cavity is subdivided into nine regions, using two transverse and two vertical planes. The transverse planes are the subcostal and intertubercular planes. The vertical planes are the right and left midclavicular planes Prof.Dr.EMAN BADAWI ELSHAL  lumbar lumbar Divisions of abdominal Inguinal Inguinal Hypogastric cavity Prof.Dr.EMAN BADAWI ELSHAL  The nine subdivisions of the abdominal cavity are: 1-Right hypochondrium.2.Epigastrium. 3-Left hypochondrium. 4-Right lumbar region or right loin. 5-Umbilical region. 6-Left lumbar region or left loin. 7-Right iliac fossa or region. 8-Hypogastrium, hypogastric region or suprapubic region. 9-Left iliac fossa or region. Prof.Dr.EMAN BADAWI ELSHAL  Stomach -The stomach is the most dilated part of the digestive tract connecting the oesophagus and small intestine. Site it lies obliquely in the left hypochondrium, epigastrium, and umbilical regions. Shape: the stomach is J- shaped Size: very distensible. The length is 10cm The capacity at birth: 30 mL Reaches: 1.5-2 liters inProf.Dr.EMAN adult BADAWI ELSHAL  Cardiac notch Abdominal Oesophagus External features: Cardiac end Stomach has three 2 orifices or openings: Lesser curvature cardiac and pyloric 2 borders or curvatures lesser and greater Duodenum curvature 2 surfaces Greater curvature Pyloric end anterior and posterior Prof.Dr.EMAN BADAWI ELSHAL Ends: a) I - Cardiac end :is directed upward &to the left – -At the junction with esophagus. -1 inch to left side of midline, It lies behind the level of left 7th costal cartilage at the level of the 11th thoracic vertebra, 45 cm from incisors, 10 cm deep to ant. abdominal wall. -Related anteriorly to left lobe of liver. It has no anatomical sphincter (only physiological). :act as valve like action which depends Prof.Dr.EMAN on:- ELSHAL BADAWI  1- Sphincter like action of the right crus of the diaphragm. 2-The thick mucosal folds of the upper end of the stomach forming a plug to the lower end of the oesophagus. 3-The abdominal part of the oesophagus is subjected to high positive intra-abdominal pressure. 4-The contraction of circular muscles fibres at lower end of the oesophagus. these fibres prevent gastro-oesophageal reflux. Prof.Dr.EMAN BADAWI ELSHAL Prof.Dr.EMAN BADAWI ELSHAL  Pyloric end: Pyloric part or end: at the junction between the stomach & small intestine Site: is directed downwards and 1 INCH to the right of the median plane at the transpyloric plane L1 vertebrae Related anteriorly to quadrate lobe of the liver It has an anatomical sphincter (thick circular muscle layer ) Marked by circular groove &. It can be detected during operation by pyloric constriction , prepyloric vein of Mayo & feeling the thickened pyloric sphincter Prof.Dr.EMAN BADAWI ELSHAL  How to identify the pylorus in surgical procedures ? Feeling of The thickness of pyloric sphincter Seeing of By detecting the pyloric constriction (which Marked by circular groove). By detecting the prepyloric vein (vein of mayo). Prof.Dr.EMAN BADAWI ELSHAL Pyloric orifice of stomach Prof.Dr.EMAN BADAWI ELSHAL  Borders of the stomach 1-Lesser curvature Is the right small concave border of stomach. It presents a notch known as angular notch or incisura angularis. It gives attachment to the lesser omentum. Related to (right and left gastric arteries and lymphatics run between the 2 layers of lesser omentum Prof.Dr.EMAN BADAWI ELSHAL  Greater curvature 2-Greater curvature Is the left large convex border of stomach. 4 times the length of lesser curvature It presents a notch at the gastro-esophogeal junction known as cardiac notch or incisura cardia. it shows the pyloric antrum opposite the angular notch. It gives attachment to 1- Greater omentum with right and left gastroepiploic vessels running between them. 2- gastro-splenic & gastro-phrenic ligaments. Related to Rt & Lt gastroepiploic vessels and lymph node between anterior 2 layers of the greater omentum Prof.Dr.EMAN BADAWI ELSHAL Parts of the stomach Subdivisions: a) Fundus : Above level of cardiac orifice it is usually distended with gas. b) Body : Between level of cardiac opening & imaginary vertical line between angular notch & the corresponding point on the greater curvature. c) Pyloric portion: consists of 3 parts: 1. Pyloric antrum: Is a dilated part below the body. 2. Pyloric canal: Is the terminal 1 inch of stomach. 3. Pyloric sphincter. Prof.Dr.EMAN BADAWI ELSHAL Prof.Dr.EMAN BADAWI ELSHAL  Surfaces of the stomach & relations A) A. The fundus: is related to diaphragm which separate it from the pericardium and heart B) 1. Antero-superior surface: The greater sac of peritoneum separates the stomach from: Anterior relations: a. diaphragm: related to upper left area of anterior surface (separating it from left lung, &pleura). b. left costal margin and c. (Left lobe of the liver) is related to the area adjoining to the lesser curvature. d. The Anterior abdominal wall is related to the lower right part of the anterior surface of the stomach. Prof.Dr.EMAN BADAWI ELSHAL  2. Postero-inferior surface: = Stomach bed Is covered by peritoneum of lesser sac separating the posterior surface of stomach from its "stomach bed" which include left crus of diaphragm, left kidney, left suprarenal gland ,, spleen and its splenic artery. , anterior surface of body of pancreas, transverse colon and mesocolon, Prof.Dr.EMAN BADAWI ELSHAL Prof.Dr.EMAN BADAWI ELSHAL Peritoneal covering and ligaments of stomach The stomach is completely covered by peritoneum except a small area on its posterior surface near the cardiac orifice. This area called bare area of the stomach and related to the left crus of the diaphragm The peritoneum covering of the anterior and the posterior surface of the stomach meet at the two curvatures to form these ligaments: Lesser omentum: connect the lesser curvature& 1st inch of the duodenum with the porta hepaits (hilum of the liver). Greater omentum: connects the right 2/3 of the greater curvature of the stomach & 1st inch of the duodenum with transverse colon and the anterior border of the body of the pancreas Gastrosplenic ligament: connects the upper left 1/3 of the greater curvature with the hilum of the spleen. Gastrophrenic ligament: connects the the fundus of the stomach with the diaphragm. Prof.Dr.EMAN BADAWI ELSHAL  blood supply of the stomach The rich arterial supply of the stomach arises from the celiac trunk and its branches. Most blood is supplied by anastomoses formed I-Along lesser curvature: 1-Lt. gastric artery (from coeliac trunk). 2- Right gastric artery (from hepatic artery ) Both right and left gastric arteries anastomose with each other on the lesser curvature. II-Along greater curvature: 1- Short gastric arteries about six branches (from splenic artery ) They pass in the gastrosplenic ligament to supply the fundus of the stomach. 2- left gastroepiploic artery (from splenic artery ) 3- Right gastroepiploic (from gastroduodenal artery from hepatic artery) left gastroepiploic and Right gastroepiploic arteries anastomose with each other on the greater curvature. Prof.Dr.EMAN BADAWI ELSHAL Blood supply of the stomach Prof.Dr.EMAN BADAWI ELSHAL Venous drainage of the stomach Prof.Dr.EMAN BADAWI ELSHAL Venous drainage of the stomach end either in the portal vein or one of its tributaries. These veins are: Left and right gastric veins Drained into portal vein. Short gastric veins and the left gastroepiploic vein end in the splenic vein. Right gastroepiploic vein ends in the superior mesenteric vein. Prof.Dr.EMAN BADAWI ELSHAL Lymph drainage drainage of stomach The gastric lymphatic vessels accompany the arteries they end in one of these lymph nodes groups: Paracardial, Left gastric. Pyloric.Hepatic. Right gastroduodenal. Pancreaticosplenic. From these lymph nodes efferent vessels drain into the celiac group of lymph nodes Prof.Dr.EMAN BADAWI ELSHAL Nerve supply of the stomach: - Sympathetic: The preganglionic sympathetic fibers arise from the spinal cord segments from T6 to T10 from the celiac plexus around the celiac trunk. passes to the celiac plexus through the greater splanchnic nerve and is distributed through the plexuses around the gastric and gastroepiploic arteries. - Parasympathetic: from both vagus nerves through the anterior and posterior gastric vagal nerves. which enter the abdomen through the esophageal hiatus Prof.Dr.EMAN BADAWI ELSHAL  motor to pyloric sphincter but inhibitory to the rest of the Sympathetic supply stomach musculature. They carry the pain sensation from the stomach. are motor to the muscle wall (↑ Parasympathetic motility of the stomach) and supply secretory to the glands of the stomach. Vagotomy (a surgical procedure of cutting the vagus nerves): It is done to cure the chronic duodenal ulcers. Gastric pain: It is usually referred to the epigastric region because the Prof.Dr.EMAN stomach is supplied by T6–T10 BADAWI spinal ELSHAL segments. Applied Anatomy: 1) Left gastric and short gastric veins receiving oesophageal veins draining abdominal part of oesophagus (portal) which anastomose with oesophegeal veins (tributaries of azygos veins ) draining thoracic part of oesophagus (systemic). In portal hypertension, opening of this porta- systemic anastomosis results in gastric and oesophageal varices. 2)The stomach has very rich blood supply and it is found that it can depend only on right gastro- epiploic vessels. This is the principle of poro- systemic disconnection operations to treat oesophageal varices. Prof.Dr.EMAN BADAWI ELSHAL