OS 206 E1 20131112 Liver, Gallbladder, And Stomach

OS  206:  Abdomen  and  Pelvis  

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Liver,  Gallbladder,  and  Stomach   Dr.  Gracia  Teodosio  

November  12,  2012  

 

   

TOPIC OUTLINE I.

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Liver A. Surface Anatomy B. Ligaments C. Fissures D. Lobes E. Surfaces F. Vascular Supply G. Lymphatics H. Nerve Supply I. Perhepatic Spaces J. Clinical Correlation Editing the Header and Footer Gallbladder A. Parts B. Vascular Supply C. Lymphatics D. Nerve Supply E. Referred Pain Stomach A. Parts B. Curvatures and Orifices C. Interior of the Stomach D. Surfaces E. Vascular Supply F. Lymphatics G. Nerve Supply H. Clinical Correlation

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Blunt trauma to the liver can cause blood and bile to enter the preperitoneal cavity, SMV cavity and the retroperitoneal area. Bile o Passes from the liver via the biliary ducts (right and left hepatic ducts) that join to form the common hepatic duct which unites with the cystic duct to form the common bile duct o Produced continuously o Accumulates between meals and is stored In the gallbladder, which concentrates bile by absorbing water and salts A. SURFACE ANATOMY Lower border: extends along a line from the tip of the right 10th rib to the left 5th intercostal space in the mid clavicular line; this may just be palpable in normal subjects, especially on deep inspiration. Upper border: follows a line passing through the 5th intercostal space on each side.

Transers’ Note: Ma’am prohibited the copying of pictures from her lecture (she also did not give a copy of her ppt presentation), so all pictures are taken from the net and previous transes. Additional information has also been added but we’ve highlighted the important points that ma’am has discussed.

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I. LIVER Largest gland in the body (2nd largest single organ next to skin) Enclosed by a tight fibrous capsule of strong connective tissue called Glisson’s capsule Weight: male 1400-1800g; female 1200-1400g o 2.5% of adult body weight o 5% of the total fetal weight because it also a hematopoetic organ Location: right upper quadrant (RUQ) of the abdomen; specifically, in the right hypochondrium, epigastric and part of the left hypochondrium area Pyramidal in shape, base found at the right and apex towards the left Surrounded by peritoneum except on the bare area of the posterior aspect of the liver, which is in contact with the diaphragm Deep to ribs 7-11 on the right side and crosses the midline toward the left nipple Protected anteriorly by the lower rib cages, and posteriorly by the muscles and bones of the abdominal wall Function: glycogen storage, bile secretion (yellowbrown or orange- green fluid that aids in the emulsification of fat) + other metabolic activities All nutrients (except fat) absorbed from the digestive tract are initially conveyed to the liver by the portal venous system

ADRE,  ALMORA,  ANARNA  

   

Figure 1. Parts of Liver B. LIGAMENTS

Figure 2. Ligaments

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  1. FALCIFORM LIGAMENT • Extends from the umbilical notch on the inferior surface of the liver porta hepatis • Ascends to the liver from the umbilicus • Subdivides the subphrenic space • As the ligaments pass over the dome of the liver, it divides into 2 leaflets: o the right leaflet becomes the coronary ligament o the left leaflet becomes the left triangular ligament o the right and left leaflets bear the ligamentum teres hepatis (round ligament)

• hepatic nerve plexuses • lymphatic vessels

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2. CORONARY LIGAMENT Upper Layer (Superior Layer): reflected from the superior surface on to the inferior surface of diaphragm • Lower Layer (Inferior Layer): reflected from the posterior surface of the right lobe of liver on to the right kidney, right suprarenal gland and inferior vena cava (IVC); also called the hepatorenal ligament; also the upper boundary of the right lumbar gutter •

3. RIGHT TRIANGULAR LIGAMENT • Begins at the extreme right of the bare area of the liver where the converging upper and lower layers of the coronary ligament fuse • Attaches the liver to the undersurface of the right leaflet of the diaphragm 4. LEFT TRIANGULAR LIGAMENT • Peritoneal fold that connects the superior surface of the left lobe of the liver to the undersurface of the diaphragm • When traced posteriorly and to the right, it joins the lesser omentum in the upper end of its fissure for the ligamentum venosum 5. ROUND LIGAMENT/ Ligamentum teres hepatis • Fibrous cord that ascends within the base of the falciform ligament from the umbilicus to the umbilical notch on the inferior surface of the left lobe of the liver • Forms free border of the falciform ligament • Runs on the fossa on the visceral surface of the liver to the porta hepatis and becomes continuous with the ligamentum venosum • Is the obliterated umbilical vein • Several weeks after birth, umbilical vein obliterates close to the umbilicus, but usually remain patent as part of the left branch of the portal vein • Ligamentum venosum: fibrous remnant of the fetal ductus venosus, located on the posterior aspect of the liver and shunts blood from the umbilical vein to the inferior vena cava, ultimately short-circuiting the liver • Porta hepatis: gastrohepatic and hepatoduodenal ligament C. FISSURES The “H” arrangement of the liver can be seen in the posterior view of the organ • The right limb of the “H” arrangement contains: o anteriorly and to the right - fossa for the gallbladder o posteriorly and to the right - groove for the IVC • The left limb of the “H” arrangement contains: o anteriorly and to the left - fissure for the ligamentum teres o posteriorly and to the left - fissure for the ligamentum venosum • The crossbar of the “H” (transverse limb) is the porta hepatis, which contains the ff: • anterior – common hepatic duct • middle – hepatic artery • posterior – hepatic portal vein Adre,  Almora,  Anarna   •

 

Figure 3. H-shaped Fissures D. LOBES ANATOMICAL DIVISION • The liver is divided into two anatomical lobes and two accessory lobes by the reflections of the peritoneum from its surface, the fissures formed in relation to those reflections and the vessels serving the liver and the gallbladder • Superficial “lobes” are not true lobes and are only secondarily related to the liver’s internal architecture • In the anterior view, you can only see the liver divided into two by the falciform ligament: the left lobe and the right lobe • In the posterior view of the liver, the “H” fissure divides the liver into right, left, quadrate and caudal lobes. • Right and left lobes do not communicate; each lobe has own arterial supply, venous and biliary drainage (for liver lobectomy, this implies less bleeding) • The caudate lobe was so named not because it is caudal in position (it is not) but because it gives rise to a “tail” in the form of an elongated papillary process. A caudate process extends to the right, between the IVC and the porta hepatis, connecting the caudate and right lobes. FUNCTIONAL SUBDIVISIONS • Although not distinctly demarcated internally, the liver has functionally independent right and left livers that are much more equal in size than the anatomical lobes (but the right liver is still somewhat larger) • Each part receives its own primary branch of the hepatic artery and hepatic portal vein and is drained by its own hepatic duct • The caudate lobe may be considered a third liver; its vascularization is independent of the bifurcation of the portal triad (it receives vessels from both bundles) and is drained by one or two small hepatic veins, which Page  2  of  9  

                                                                                                                                                                                     

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enter directly into the IVC distal to the main hepatic veins The liver can be further divided into four divisions and then into eight surgically respectable hepatic segments, each served indepently by a secondary or tertiary branch of the portal triad

LESSER OMENTUM • Encloses the portal triad • Passes from the liver to the lesser curvature of the stomach and the first 2 cm of the superior part of the duodenum • The thick, free edge of the lesser omentum extends between the porta hepatis and the duodenum (the hepatoduodenal ligament) and encloses the structures that pass through the porta hepatis • Hepatogastric ligament: connects the stomach to the liver; sheet- like remainder of the lesser omentum which extends between the groove for the ligamentum teres and the lesser curvature of the stomach E. SURFACES

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Portion of the supracolic compartment of the peritoneal cavity immediately inferior to the liver Hepatorenal recess (Hepatorenal pouch, Morison’s pouch) o Posterosuperior extension of the subhepatic space, lying between the right part of the visceral surface of the liver, the right kidney and the suprarenal gland o Fluid draining from the omental bursa flows into this recess o Gravity-dependent part of the peritoneal cavity in the supine position o Communicates anteriorly with the right subphrenic recess o

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Note: The liver is entirely covered by peritoneum except: 1. Bare area o attached to the retroperitoneal tissue which is areolar tissue with lymphatics and minor veins o in direct contact with the diaphragm o demarcated by the reflection of the upper peritoneum from the diaphragm to it as the anterior (upper) and posterior (lower) layers of the coronary ligament 2. Groove for IVC 3. Gallbladder fossa 4. Porta hepatic F. VASCULAR SUPPLY

Figure 4. Position of Liver in the Body 1. ANTEROSUPERIOR • Fits snugly into the cupola of the diaphragm • Separates it from the overlying pleural cavities and pericardium • Pus can go directly into the lung through this surface • Smooth and dome-shaped • Subphrenic recesses o Superior extension of the peritoneal cavity (greater sac) o Between the diaphragm and the anterior and superior aspects of the diaphragmatic surface of the liver o Separated into the right and left recesses by the falciform ligament 2. POSTEROSUPERIOR • IVC found in the posterior surface of caudate lobe • Suprarenal impression • Bare area of liver 3. RIGHT LATERAL • Related to the right lateral surface of the diaphragm from the 7th to the 11th right midaxillary ribs 4. INFERIOR • Separates diaphragmatic and visceral surfaces • In contact with the following and forms impressions on the surface of the liver o Stomach o Colon o Kidney o Duodenum o Esophagus o Right suprarenal gland • Subhepatic space Adre,  Almora,  Anarna  

 

Figure 5. Vascular System of Liver 1. 2. 3.

Hepatic artery – carries oxygenated blood Portal vein – carry venous blood Renal, Phrenic, lumbar, intercostals veins receive blood from the mesenteric, pancreatic and other veins

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Arterial Supply Has double blood supply from the hepatic artery (2025%) and the hepatic portal vein (70-80%) Hepatic artery o Branch of the celiac trunk o May be divided into the common hepatic artery from the celiac trunk to the origin of the

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gastroduodenal artery to the bifurcation of the hepatic artery o Blood distributed initially to nonparenchymal structures (eg intrahepatic bile ducts) The right and left hepatic arteries carry oxygenated blood to the liver. At or close to the porta hepatis, the hepatic artery and the hepatic portal vein terminate by dividing into right and left branches. These primary branches supply the right and left livers, respectively. Within each part, the simultaneous secondary branchings of the portal vein and hepatic artery (portal pedicles) are consistent enough to supply the medial and lateral divisions of the right and left liver, with three of the four secondary branches undergoing further (tertiary) branchings to supply independently seven of the eight hepatic segments Hepatic portal vein o Short, wide o Formed by the union of the superior mesenteric and splenic veins o Ascends anterior to the IVC as part of the portal triad in the hepatoduodenal ligament o Portal blood, containing about 40% more oxygen than blood returning to the heart from the systemic circuit, sustains the liver parenchyma (hepatocytes) o Carries virtually all of the nutrients absorbed into and bypass the liver via the lymphatic system

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which accompany the ramification of the portal triad and hepatic veins • Most lymph is formed in the perisinusoidal spaces (of Disse) and drains to the deep lymphatics in the surrounding intralobular portal triads • Most of the deep lymph vessels in the liver converge at the porta hepatis and end in the hepatic lymph nodes scattered along the hepatic vessels and ducts of the lesser omentum • Superficial lymphatics from the anterior aspects of the diaphragmatic and visceral surfaces of the liver and deep lymphatic vessels accompanying the portal triads>portahepatis>hepatic lymoh nodes (scattered along the hepatic vessels and ducts in the lesser omentum)>celiac lymph nodes>chyle cistern (cisterna chili, a dilated sac at the inferior end of the thoracic duct)>thoracic duct • Superficial lymphatics in the posterior aspects of the diaphragmatic and visceral surfaces of the liver drain toward the bare area of the liver>Phrenic lymph nodes OR • Join deep lymphatics that have accompanied the hepatic veins converging on the IVC, and pass with this large vein through the diaphragm>posterior mediastinal lymph • Posterior surface of the left lobe>esophageal hiatus of the diaphragm>left gastric lymph nodes • Anterior central diaphragmatic surface along the falciform ligament>parasternal lymph nodes

b. Venous drainage • There are 3 major hepatic veins: Right, Central, and Peripheral • These pass upwards and backwards to drain into the IVC at the superior margin of the liver. • Central veins in lobules are to hepatic veins to IVC • R,C , and L are intersegmental in their distribution and function, draining parts of the adjacent segments • Central veins of the hepatic parenchyma→collecting veins→hepatic veins→IVC (inferior to diaphragm) • Attachment of veins to IVC helps hold the liver in position OBSTRUCTION OF THE PORTAL CIRCULATION 1. Lower part of the rectum, from superior to inferior middle rectal 2. At the esophagus, from the coronary to esophageal veins 3. In the falciform and round ligament, from the porta hepatic to tributaries of the epigastric 4. In the retroperitoneal region o tributaries of the splenic and pancreatic veins anastomose with left renal vein o splenic and colic to the lumbar veins o veins of bare area communicate with the veins of diaphragm and right internal thoracic vein Note: Veins tend to be dilated and tortuous (i.e. convoluted, twisted) in the following areas: o Anal – hemorrhoid o Gastroesophageal – esophageal varices (vomits blood) o Paraumbilical – caput medusa (can be due to liver serosis or any obstruction!) Note: The veins of Retzius connect intestinal veins with inferior vena cava and its retroperitoneal branches

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G. LYMPHATICS The liver is a major lymph-producing organ. Between ¼ to ½ of the lymph entering the thoracic duct comes from the liver Superficial lymphatics in the subperitoneal fibrous capsule of the liver (Glisson’s capsule), which forms its outer surface, and as deep lymphatics in the connective tissue, Adre,  Almora,  Anarna  

 

Figure 6. Lymphatics of the Liver

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H. NERVE SUPPLY Contains both sympathetic and parasympathetic fibers via the hepatic plexus (largest derivative of the celiac plexus) Receives filaments from the L and R vagus and R phrenic nerves Nerve fibers accompany the vessels and biliary ducts of the portal triad for vasoconstriction (other functions are unclear) Hepatic plexus o Largest derivative of the celiac plexus o Accompanies the hepatic artery and portal vein and their branches – enters liver through porta hepatic Consists of sympathetic fibers from the celiac plexus and parasympathetic fibers from the anterior and posterior vagal trunks

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Figure 7. Innervation of Liver

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I. PERIHEPATIC SPACES Spaces between diaphragm, transverse colon and transverse mesocolon o Suprahepatic: between diaphragm and liver. o Infrahepatic: between visceral surface of liver and transverse colon/mesocolon.

J. CLINICAL CORRELATIONS LIVER BIOPSY • The needle is directed through the right 10 in the midaxillary line • Before the physician takes the biopsy, the person is asked to hold his or her breath in full expiration to reduce the costodiaphragmatic recess and to lessen the possibility of damaging the lung and contaminating the pleural cavity HEPATOMEGALY • Hepatic enlargement caused by congestive heart failure, tumors and bacterial/viral diseases such as hepatitis • Inferior edge may be readily palpated below the right costal margin and may even reach the pelvic brim in the right lower quadrant of the abdomen • Any rise in central venous pressure is directly transmitted to the liver (IVC and hepatic veins lack valves), which enlarges as it becomes engorged with blood. Marked temporary engorgement stretches the fibrous capsule of the liver, producing pain around the lower ribs, particularly in the right hypochondrium. This engorgement, particularly in conjunction with increased or sustained diaphragmatic activity, has been proposed as an underlying cause of “runner’s stitch”. CIRRHOSIS OF THE LIVER • Progressive destruction of hepatocytes (parenchymal liver cells) and replacement by fat and fibrous tissue • Caused by chronic alcoholism (manin) and also industrial solvents such as carbon tetrachloride • Alcoholic cirrhosis • Most common of many causes of portal hypertension • Characterized by enlargement of the liver resulting from fatty changes and fibrosis • The liver has great functional reserve, and so the metabolic evidence of liver failure is late to appear • Fibrous tissue surrounds the intrahepatic blood vessels and the biliary ducts, making the liver firm, and impeding the circulation of blood through it (portal hypertension) • Treatment includes surgical creation of a portosystemic or portocaval shunt, anastomosing the portal and systemic venous systems SUBPHRENIC ABSCESSES • Peritonitis may result in the formation of localized abscesses in various parts of the peritoneal cavity such as in a subphrenic recess or space • More common on the right side because of the frequency of ruptured appendices and perforated duodenal ulcers • Because the right and left subphrenic recesses are continuous with the hepatorenal recess (the lowest parts of the peritoneal cavity when supine), pus from a subphrenic abscess may drain into one of the hepatorenal recesses, especially when patients are bedridden • A subphrenic abscess is often drained by an incision inferior or through, the bed of the 12th rib, obviating Adre,  Almora,  Anarna  

 

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the formation of an opening in the pleura or peritoneum An anterior subphrenic abscess is often drained through a subcostal incision located inferior and parallel to the right costal margin

HEPATIC LOBECTOMIES AND SEGMENTECTOMY • Lobectomy: removal of the right or left part of the liver without excessive bleeding (most injuries to the liver involve the right liver) • Segmentectomy: removal of only the segments that have sustained a severe injury with the use of a cauterizing scalpel and laser surgery. The right, intermediate, and left hepatic veins serve as guides to the lanes (fissures) between the hepatic divisions RUPTURE OF THE LIVER • The liver is easily injured because it is large, fixed in position, and friable (easily crumbled). • Often a fractured rib that perforates the diaphragm tears the liver • Liver lacerations often cause considerable hemorrhage and right upper quadrant pain LIVER CANCER • The liver is also a common site of metastatic carcinoma (secondary cancers spreading from organs drained by the portal system of veins) • Cancer cells may also pass to the liver from the thorax, especially from the breast, because of the communications between thoracic lymph nodes and the lymphatic vessels draining the bare area of the liver • Metastatic tumors form hard, rounded nodules within the hepatic parenchyma • • • •

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II. GALL BLADDER 7-10cm long Lies in the fossa for the gallbladder on the visceral surface of the liver Pear-shaped organ found at RUQ Naturally lies anterior to the superior part of the duodenum with its neck and cystic duct immediately superior to the duodenum (but not seen in dissection or atlases because it’s normally retracted superiorly to be exposed) Can hold up to 50 mL of bile Peritoneum completely surrounds the fundus of the gallbladder and binds its body and neck to the liver. The hepatic surface of the gallbladder attaches to the liver by connective tissue of the fibrous capsule of the liver A. PARTS

Figure 8. Parts of Gallbladder

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  1. FUNDUS • The tip of the fundus is the angle formed by the lateral border of the rectus abdominis and the 9th costal cartilage • The rounded edge of the gallbladder (GB) is 0.5-1cm from the free edge of the inferior border of the right lobe of the liver • It is directed inferiorly, anteriorly, and to the right, in contact with the posterior surface of the anterior abdominal wall and the descending part of the duodenum

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Adhesions between the GB, flexure, and right side of the transverse colon are common. Billary stones can pass directly to the large bowel. Complication of close coaption of the GB to the visceral surface of the liver allows for early spread of carcinoma. B. VASCULAR SUPPLY

2. BODY • It is directed superiorly, posteriorly and to the left of the fundus. • It is in contact with the visceral surface of the liver and is attached to its bed areolar tissue that contains many lymphatics and veins. • It is in contact with the right part of transverse and superior part of the duodenum. 3. INFUNDIBULUM • It is the tapering transitional area between the body and neck. • It is attached to the first part of the duodenum by the cholecystoduodenal ligament (avascular, peritoneal fold derived from the right border of the hepatoduodenal ligament). It has great importance in the operative search for major vascular and ductal structures. • The Hartman’s pouch is the bulging inferior surface of the infundibulum. • It is used to mark the positions of the neck and cystic duct of the gallbladder, which the pouch overhangs. 4. NECK • It is the narrowed, tapering structure directed toward the porta hepatis. • It is 5-6 mm long, forms an “S” and is constricted at its junction with the cystic duct. • The cystic duct is 2-4 cm long and connects the gallbladder to the common hepatic duct which passes between the layers of the lesser omentum to become the common bile duct. The mucosa of the neck spirals into the spiral valve of Heister.

Figure 10. Inferior View of the Gallbladder 1. ARTERIAL SUPPLY

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2. VENOUS DRAINAGE • There is no major cystic vein. • The cystic veins pass directly into the liver and end in the portal capillary system.

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Figure 9. Ductal Structures of Gallbladder • Spiral valve of Heister: • Helps keep the cystic duct open (to easily divert bile into GB when the distal end of the bile duct is closed by the sphincter of the bile duct and/or hepatopancreatic sphincter, or bile can pass to the duodenum as the GB contracts • Offers additional resistance to sudden dumping of bile when the sphincters are closed, and intra-abdominal pressure is suddenly increased (e.g. sneeze or cough)

CYSTIC ARTERY o Commonly arises from the right hepatic artery in the triangle between the common hepatic duct, cystic duct, and visceral surface of the liver, the cystohepatic triangle (of Calot). o Supplies the gallbladder and cystic duct. o Divides into two, supplying: o The free surface of the gallbladder o The attached surface of the gallbladder o Can originate from: o Right and left hepatic arteries o Common hepatic artery o Superior mesenteric artery

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C. LYMPHATICS The lymphatic drainage of the GB is to the hepatic lymph nodes, often through cystic lymph nodes located near the neck of the GB. Efferent lymphatic vessels from these nodes pass to the celiac lymph nodes. D. NERVE SUPPLY The nerves follow the path of the cystic artery. They come from celiac plexus (sympathetic and visceral afferent [pain] fibers), vagus nerve (parasympathetic), and right phrenic nerve (sensory). E. REFERRED PAIN Irritation in the liver (near the diaphragm) will manifest as pain in the neck and shoulder region (C3, C4, C5). Shoulder pain could also mean biliary stones. Irritation in the gallbladder will manifest as pain in T7 and T9 (until posterior) and infrascapular area. If the phrenic nerve is irritated, it will cause ipsilateral pain in the shoulder and neck. Abdominal pain in the crouching position may suggest appendicitis. Cholecystitis is gallbladder inflammation (tenderness occurs at ipsilateral side of RUQ and shoulder)

CLINICAL IMPORTANCE OF RELATIONSHIP OF GB TO RIGHT COLON AND HEPATIC FLEX Adre,  Almora,  Anarna  

 

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III. STOMACH Most dilated part of the alimentary canal between the esophagus and small intestine Lies in the epigastric, umbilical and left hypochondriac region o Hypochondriac region = region on either side of the abdomen beneath the cartilages of the false ribs [chondros = cartilage] It is intraperitoneal and covered by visceral peritoneum (except where blood vessels run along its curvature) Relations to other organs: o Anteriorly: related to the diaphragm, left lobe of liver, anterior abdominal wall o Posteriorly: related to the omental bursa and pancreas; the posterior surface of the stomach forms most of the anterior wall of omental bursa A. PARTS

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4. CARDIA • Part surrounding the cardiac orifice which is the superior opening or inlet of the stomach B. CURVATURES AND ORIFICES GREATER CURVATURE • From the cardiac notch, it curves upwards towards the level of the 5th intercostal space, then downward and forward up to the pyloric region, where the right and left gastroepiploic vessels anastomose LESSER CURVATURE • Continuous posteriorly with the right margin; where the right and left gastric arteries anastomose. CARDIAC ORIFICE • Usually lies posterior to the 6th left costal cartilage, ~4 cm from the median plane at the level of the T11 vertebra. PYLORIC ORIFICE • The opening into the duodenum • Its position is usually indicated by a circular groove on the surface of the organ termed as the pyloric constriction, which indicates the position of the pyloric sphincter (formed by circular muscle of stomach) • The two layers of the lesser omentum extend around the stomach and leave its greater curvature as the greater omentum.

Figure 10. Parts of Stomach 1. FUNDUS • The dilated superior part that is related to the left dome of the diaphragm and is limited inferiorly by the horizontal plane of the cardiac orifice • Cardiac notch is between the esophagus and the fundus • Reaches the left 5th intercostal space 2. BODY • The major portion of the stomach between the fundus and the pyloric antrum • Lies in contact with the left costal margin and upper anterior abdominal wall on the left side as it descends from the level of T10 to the middle lumbar vertebral area 3. PYLORIC REGION • Funnel-shaped outflow region of the stomach; its wide part, the pyloric antrum, leads to the pyloric canal, which is the narrow part • The pyloric region is divided into smaller regions by a groove, the sulcus intermedius (separates pyloric antrum and pyloric canal) • Pyloric antrum o Part of the pyloric region that is more proximal to the stomach proper, found near midline position and begins to ascend as it blends into the pyloric canal; it is the entryway to the pyloric canal (Latin, pylorus meaning ‘gatekeeper’; antrum meaning ‘cave’) • Pyloric canal o The more distal part of the stomach proper; it is located 2-3cm from the pylorus • Pyloric canal and sphincter lie on the transpyloric plane that horizontally transverses the interverterbral disc between L1 and L2 vertebrae • Pylorus: distal, sphincteric region of the pyloric part, is a marked thickening of the circular layer of smooth muscle, which controls discharge of the stomach contents through the pyloric orifice into the duodenum Adre,  Almora,  Anarna  

 

Figure 11. Greater and Lesser Curvature of the Stomach C. INTERIOR OF THE STOMACH RUGAE (GASTRIC FOLDS) • Temporary longitudinal folds formed when gastric mucosa is contracted (in contrast to permanent folds of small intestine) • Diminish and obliterate as the stomach is distended. GASTRIC CANAL • Temporarily formed during swallowing between the longitudinal gastric folds of the mucosa along the lesser curvature • Forms because of the firm attachment of the gastric mucosa to the muscular layer, which does not have an oblique layer at this site. • Saliva and small quantities of masticated food and other fluids pass through the gastric canal to the pyloric canal when the stomach is mostly empty D. SURFACES ANTEROSUPERIOR SURFACE • The pressure exerted by a dilated fundus against the undersurface of the left leaf of the diaphragm is Page  7  of  9  

                                                                                                                                                                                     

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  responsible for many pulmonary and cardiac symptoms • Clinical correlation: o The near proximity of the heart to the stomach is illustrated by a case where a thorn (“tinik”) has been swallowed and had found its way throug the diaphragm and pericardium into the wall and cavity of the right ventricle POSTEROINFERIOR SURFACE • The stomach bed is composed of the: o Left suprarenal gland o Upper part of the front left kidney o Splenic artery o Anterior surface of the pancreas o Diaphragm o Transverse mesocolon o Left colic flexure E. VASCULAR SUPPLY ARTERIAL SUPPLY • Most blood is supplied by anastomoses formed by the: o Right and Left Gastric arteries – along the lesser curvature o Right and Left Gastro-Omental arteries – along the greater curvature • The fundus and upper body receive blood from the short and posterior gastric arteries • 3 primary branches of the celiac trunk o Left Gastric Artery o Splenic Artery o Common Hepatic Artery

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Figure 13. Venous Drainage of the Stomach F. LYMPHATICS **This section was not discussed. We just took this from 2017 trans for further knowledge :)

Table 1. Lymphatic Circulation of the Stomach The lymphatic vessels can be found in these areas: 1. Along the left part of the lesser curvature 2. Along the greater curvature and most of pyloric region 3. Along the left of the greater curvature 4. Along a small part of the pyloric

Figure 14. Lymphatics of the Stomach Figure 12. Arterial Supply of the Stomach VENOUS DRAINAGE • Gastric veins parallel the arteries in position and course. • Portal vein - main draining vein formed by the union of the splenic and superior mesenteric vein; receives from: o Right and Left Gastric veins o Splenic vein - receives from the short gastric veins and left gastro-omental veins o Superior mesenteric vein (SMV)- receives from the right gastro-omental vein • Prepyloric vein - ascends over the pylorus to the R gastric vein; used for identifying the pylorus.

G. NERVE SUPPLY

Figure 15. Distribution of Vagal Nerve to Stomach Adre,  Almora,  Anarna  

 

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2018 IA

Liver,  Gallbladder,  and  Stomach  

  PARASYMPATHETIC NERVE SUPPLY • Anterior Vagal Trunk o Derived mainly from the left vagus nerve runs toward the lesser curvature, where it gives off hepatic and duodenal branches,which leave the stomach in the hepato-duodenal ligament. o It continues along the lesser curvature, giving rise to anterior gastric branches. • Posterior Vagal Trunk o Larger of the two, it is derived mainly from the right vagus nerve, enters the abdomen on the posterior surface of the esophagus and passes toward the lesser curvature of the stomach. o It supplies branches to the anterior and posterior surfaces of the stomach. o It gives of a celiac branch, which runs to the celiac plexus, and then continues along the lesser curvature, giving rise to posterior gastric branches.

you as anatomates!! Naaappreciate ko talaga kayo!! ^___________^ And thank you din pala to our cool friends from tables 1 and 3! God bless!!