OS 206: Abdomen and Pelvis - Stomach, Liver, Gallbladder PDF

OS 206: ABDOMEN AND PELVIS STOMACH, LIVER, GALLBLADDER UPCM 2029 | Dr. Karen June Dumlao | LU3 A.Y. 2024-2025 OUTLINE I.​ Liver III.​ Stomach A.​ Surface Anatomy...

OS 206: ABDOMEN AND PELVIS STOMACH, LIVER, GALLBLADDER UPCM 2029 | Dr. Karen June Dumlao | LU3 A.Y. 2024-2025 OUTLINE I.​ Liver III.​ Stomach A.​ Surface Anatomy A.​ Position B.​ Surfaces B.​ Parts C.​ Recesses C.​ Interior D.​ Ligaments D.​ Relations E.​ Divisions E.​ Neurovasculature F.​ Neurovasculature F.​ Clinical Correlations G.​ Biliary Duct IV.​ Dissection Videos H.​ Clinical Correlates V.​ References II.​ Gallbladder A.​ Parts of the Gallbladder B.​ Neurovasculature C.​ Clinical Correlates Figure 2. Palpating the liver(Moore, 2023) Steps I.​ LIVER 1.​ Place left hand posteriorly behind the right lower rib LEARNING OBJECTIVES 2.​ Place right hand on right upper quadrant 1.​ Describe the structure and function of the liver, including its ​ Lateral to the rectus abdominis, inferior to the costal margin lobes and fissures. 3.​ Ask patient to take a deep breath and hold 2.​Orientation of the liver and differentiate between diaphragmatic 4.​ Press your right hand postero-superiorly and visceral surfaces. 5.​ Pull anteriorly with left hand 3.​Identify the ligaments associated with the liver. 6.​ Check for enlargement or masses 4.​Become familiar with the location of the liver in the abdomen. ​ Ask patient if they feel any pain or discomfort during palpation 5.​Understand the anatomical relations of the lIver. 6.​Blood supply, venous drainage, lymphatic drainage and nerve B.​ SURFACES supply. ​ LARGEST gland in the body ​ LARGEST visceral organ ​ Approx. 1500 g ○​ Accounts for 2.5% of adult body weight ​ Filipino translation: atay A.​ SURFACE ANATOMY ​ Mainly in the right upper quadrant ○​ Most of right hypochondrium ○​ Upper epigastrium ○​ Extends slightly into left hypochondrium ​ Protected by the thoracic cage and diaphragm ○​ Deep to 7th-11th ribs ​ Crosses midline to left nipple Figure 3. Surfaces of the liver(Moore, 2023) DIAPHRAGMATIC SURFACE ​ Supero-anterior area ​ Covered in visceral peritoneum ○​ Exception: Bare area ​ In direct contact with the diaphragm VISCERAL SURFACE ​ Postero-inferior concave area ​ Covered with visceral peritoneum ○​ EXCEPTIONS: fossa of gallbladder; area of porta hepatis ​ Two sagittal fissures connected via the transverse porta hepatis ○​ Overall, fissures form an ‘H’ shape Figure 1. Surface projection of the liver(Moore, 2023) PALPATING THE LIVER ​ Can be palpated in the supine position ○​ Must be done during deep inspiration ​ Allows inferior movement of the diaphragm and liver ○​ Lower border: tip of 10th rib to left 5th intercostal space along the midclavicular line ○​ Upper border: follows line passing through 5th intercostal space on each side Trans 2 TG14: Guinto V., Gunnacao, Hindac, Ignacio, Ilagan, Ipac, Karamihan TH: Ilagan 1 of 13  ○​ Location: between the diaphragm and right lobe of the liver ​ Left Triangular Ligament ○​ Latin: Ligamentum triangulare sinistrum hepatis ○​ Forms the coronary ligament’s left end ○​ Formed by falciform ligament and lesser omentum (Netter 8th ed.) ○​ Location: between the diaphragm and left lobe of the liver FALCIFORM LIGAMENT OF THE LIVER Figure 4. Fissures on the visceral surface of the liver(Moore, 2023) Table 1. VISCERAL SURFACE FISSURES FISSURE DESCRIPTION ​ Formed by: Figure 7. Falciform ligament of the liver. ○​ Anteriorly: Fossa of ​ Latin: Ligamentum falciforme hepatis Right Sagittal Fissure gallbladder ​ On the most anterior surface of the liver ○​ Posteriorly: Groove for the ​ From the antero-inferior side of the liver to the anterior abdominal Vena Cava wall ​ Formed by round ligament and ligamentum venosum ROUND LIGAMENT OF THE LIVER Left Sagittal Fissure / Umbilical ○​ Round ligament: remnant of Fissure umbilical vein ○​ Ligamentum venosum: remnant of ductus venosus C.​ RECESSES Taken from Batch 2028 Trans ​ Subphrenic Recess ○​ Superior extension of the greater sac ○​ On each side: Left and Right Figure 8. Round ligament of the liver (L & R): inferior view (R). ​ Separated by the falciform ligament ​ Latin: Ligamentum teres hepatis ​ Subhepatic Space ​ Formed at the inferior end of the liver by the falciform ligament’s ○​ Supracolic compartment portion of the peritoneal cavity free edge inferior to the liver ​ Divides the liver into its left and right anatomical lobes ​ Hepatorenal Recess/Pouch (Morison Pouch) ​ Divides functional left lobe into its median and lateral sections. ○​ Subhepatic space posterosuperior extension ​ Connects the liver to the umbilicus ​ Lies between the visceral surface (right side) of the liver, right kidney, and suprarenal gland LIGAMENTUM VENOSUM ○​ Communicates anteriorly with right subphrenic recess ○​ Important as it’s a site for fluid collection D.​ LIGAMENTS CORONARY LIGAMENT OF THE LIVER Figure 5. Coronary ligament of the liver (L & R); inferior view (R). ​ Latin: Ligamentum coronarium hepatis ​ Attaches the liver to the diaphragm ​ Reflection of the peritoneum ​ Two portions: ○​ Anterior ○​ Posterior: continuous with lesser omentum (Netter 8th ed.) Figure 9. Ligamentum venosum (Moore 9th ed.) ​ Between the two portions is the bare area of the liver ​ Remnant of fetal ductus venosus TRIANGULAR LIGAMENTS OF THE LIVER ​ Extended in fetus between umbilical vein and IVC E.​ DIVISIONS ANATOMICAL LOBES ​ Externally, the liver is divided into two anatomical and two accessory lobes by the: ○​ Reflections of the peritoneum from its surface ○​ Fissures formed from the reflections ○​ Vessels serving the liver and gallbladder Figure 6. Right triangular ligament (L); Left triangular ligament (pointed structure on the R, NOT the green-shaded). ​ Right Triangular Ligament ○​ Latin: Ligamentum triangulare dextrum hepatis ○​ Formed by the meeting of the anterior and posterior portions of the coronary ligament at the right end OS 206 Stomach, Liver, Gallbladder 2 of 13  ​ Part of the Anatomical right lobe ​ Part of the Functional left lobe ○​ EXCEPT for the Caudate lobe (hepatic segment 1), which has independent vascularization and drainage, the liver is divided into the right and left liver based on the primary division of the portal triad into its left and right branches ○​ Each of the four divisions receive a secondary branch of the portal triad Functional Left Lobe ​ Divided into left medial and left lateral section along the falciform ligament and through fissures of the ligamentum venosum and ligamentum teres ​ Left Lateral Section ○​ Left anatomical lobe ○​ Lies left to the umbilical fissure and falciform ligament ​ Left Medial Section Figure 10. Anterior surface of the Anatomic Right lobe (Green) and Left lobe ○​ Parts of right anatomical liver (Unhighlighted) ○​ Lies between the Cantlie’s line and falciform ligament ​ The lobes are separated by three peritoneal folds: ○​ Falciform ligament ○​ Ligamentum venosum ○​ Round ligament of the liver Anatomical Right Lobe ​ Right lobe is larger than the left ​ Grooves in its inferior surface represent impressions of the following: ○​ Duodenal impression (Duodenum) ○​ Colic impression (Colon) ○​ Renal impression (Right kidney) Anatomical Left Lobe ​ Smaller and flatter than the anatomical right love ​ Gastric impression (stomach) can be appreciated in its inferior surface Figure 13. Functional divisions of the liver: Lobes, Sections, Hepatic segments ​ Visceral surface faces the stomach and esophagus Functional Right Lobe Accessory Lobes ​ Divided into right anterior and right posterior section through an oblique line that passes antero-posteriorly from the midpoint of the right lobe to the groove of the IVC ​ Right anterior section ○​ Contains the superior (VIII) and inferior (V) hepatic segment ​ Right posterior section ○​ Contains superior (VII) and inferior (VI) segment Hepatic Segments ​ Each section is further divided into two hepatic segments ​ Numbered from 1-8 in a counterclockwise direction around the porta hepatis Table 2. FUNCTIONAL DIVISIONS OF THE LIVER: LOBES, SECTIONS, HEPATIC SEGMENTS SEGMENT SURGICAL TERM LATERALITY LOBE I Posterior Caudate II Lateral Left III Left Lateral Anterior Left IV Left Medial Figure 11. Postero-inferior view of the liver highlighting the Quadrate lobe (Yellow) V Anterior Medial and Caudate Lobe (Blue)(Moore, 2023) Quadrate Lobe VI Right Anterior Lateral Right Right ​ Part of the anatomical right lobe VII ​ Bordered by the gallbladder, hilum of the liver, and the round Posterior Lateral VIII ligament Caudate Lobe Question: Is there communication between the R and L hepatic ​ Part of the anatomical right lobe arteries/ducts and the R and L hepatic portal veins? ​ Can be considered as its own lobe due to having an independent Answer: None. This is why hepatic lobectomies (removal of the vascularization and drained by 1-2 small hepatic veins which enters right or left liver) are possible without excessive bleeding. directly into the inferior vena cava (IVC) FUNCTIONAL LOBES F.​ NEUROVASCULATURE ARTERIAL SUPPLY ​ Liver receives blood from: ○​ Hepatic artery (20%) ​ Branch of the celiac trunk ○​ Hepatic portal vein (80%) ​ Formed by the superior mesenteric and splenic veins Figure 12. Anterior and posterior view of the Functional Left and Right livers, along with the Cantlie line. ​ Cantlie line ○​ Done by drawing a line through the midline of gallbladder (fundus) to the IVC ○​ Divides the liver into equal-sized functional left and right lobes ​ Approximates anterior aspect of the middle of the hepatic vein ​ Demarcates the left and right parts of the liver ○​ Accessory Lobes (Caudate and Quadrate Lobe) OS 206 Stomach, Liver, Gallbladder 3 of 13 Porta Hepatis Branches of Proper Hepatic Artery Figure 14. Porta hepatis. ​ AKA “Hilum of the Liver” ​ Transverse fissure located between the caudate and the quadrate lobes ​ Transmits the following: ○​ Main structures: Hepatic portal vein, proper hepatic artery, Figure 18. Branching Vessels in the Liver. common hepatic duct ​ Primary Branching ​ These three structures form the portal triad ○​ Vessels divide into left and right branches to supply the left and ○​ Others: Lymphatic vessels, hepatic branch of the vagus nerve, right parts of the liver respectively sympathetic nerves ​ Secondary Branching ○​ From the right and left primary branch → supply the medial and lateral divisions of the right andleftL liver ​ Tertiary branching ○​ From 3 of the 4 secondary branches ○​ Supplies 7 of 8 hepatic segments VENOUS DRAINAGE Figure 15. Portal triad at the free border of the lesser omentum. Common hepatic artery (CHA) (UPCM 2028 Trans) ​ Ascends towards the porta hepatis and bifurcates into two terminal branches: Figure 19. Venous drainage cycle ○​ Proper hepatic artery Hepatic portal veins (HPV) ○​ Gastroduodenal artery Proper Hepatic Artery Figure 16. Proper Hepatic Artery as Part of the Portal Triad: Inferior (Left) and Posterior (Right) views. Figure 20. Hepatic Portal Vein: Posterior (Left Upper), Inferior (Right Upper), and Anterior (Lower) views. ​ NOT the same as the hepatic veins Figure 17. Primary Branching of the PHA into the Left and Right Branches. ​ Part of the portal venous system ​ Ascends towards the liver anterior to the portal vein ○​ Portal blood contains about 40% more oxygen than blood ​ Bifurcates into right and left proper hepatic artery before returning to the heart from the systemic circuit and sustains the entering the liver liver parenchyma (liver cells or hepatocytes) (Moore 9th ed.) ​ NOT a true vein because it DOES NOT directly return blood to the heart ​ Functions: ○​ Conducts blood containing both nutrients and toxins from food to the liver for detoxification ○​ Carries all absorbed nutrients by the GI tract EXCEPT lipids which are absorbed by lymphatics and bypass the liver (Moore 9th ed.) ○​ Receives blood from the gallbladder, spleen, and pancreas (Batch 2028 Trans) OS 206 Stomach, Liver, Gallbladder 4 of 13 ​ Valveless; 8cm (3in) long ​ Located in the upper right quadrant Splenic vein ​ Courses obliquely through the liver, behind the duodenum ○​ Runs along the right free border of the lesser omentum with the other members of the portal triad ​ Splenic-Mesenteric Confluence ○​ HPV is formed by the convergence of the superior mesenteric vein (SMV) and splenic vein ○​ SMV + Splenic Vein → Portal Vein → Liver (detoxification: filter exits via bile/urine) → IVC → heart Figure 23. Splenic Vein (Green), Inferior Mesenteric Vein (Arrow). ​ Receives blood from the inferior mesenteric vein (IMV) ○​ Drains the rectum, sigmoid, descending and distal transverse colon ​ Also drains stomach, spleen, and pancreas Inferior vena cava (IVC) Figure 21. Splenic-Mesenteric Confluence: Splenic Vein (SV) and Superior Mesenteric Vein (SMV). ​ HPV anastomoses with the following: ○​ Esophageal veins ○​ Rectal venous plexus ○​ Superficial veins of the abdomen’s skin Hepatic veins ​ Valveless veins draining the liver ​ Right and left hepatic vein drain the right and left lobe of the liver ​ Intermediate vein drains the caudate lobe ​ Intrahepatic vein drains the blood from the liver to the IVC Question: Why is it important to note that the hepatic veins DO NOT contain valves? Answer: ​ Unimpeded blood flow to the IVC. Figure 24. Inferior Vena Cava: Posterior View. ○​ Unlike peripheral veins, hepatic veins rely on pressure gradients to drain blood from the liver directly to the IVC. The lack of ​ Main vein that carries deoxygenated blood from the lower half of valves ensures continuous and efficient venous drainage the body to the IVC without resistance. ​ Located in the retroperitoneal space on the posterior wall of the ​ Risk of retrograde flow and hepatic congestion. abdominal cavity to the right of the abdominal aorta ○​ Since there are no valves to prevent backflow, right heart ​ Runs directly behind the liver and is firmly bound to its posterior failure or increased central venous pressure can lead to surface by a ligament hepatic congestion (AKA nutmeg liver). ​ Receives tributaries from: ○​ Clinical correlates: Budd-Chiari syndrome and Hepatic vein ○​ Common Iliac Veins thrombosis ○​ Lumbar Veins ​ Can cause liver dysfunction due to venous outflow ○​ Right Gonadal Vein obstruction ○​ Renal Veins ​ There is a pathway for infections and metastasis. ○​ Right Suprarenal Vein ○​ Open venous system allows infection or tumor emboli to spread ○​ Inferior Phrenic Vein easily from systemic circulation into the liver ○​ Hepatic Veins ○​ This is why liver abscess and metastatic liver cancer are ​ DOES NOT drain blood directly from the gut common. ○​ Blood has to pass through the HPV into the liver to remove contaminants and for nutrient processing Superior mesenteric vein (SMV) LYMPHATIC DRAINAGE Figure 22. Right: Superior Mesenteric Vein (Green Arrow), Left: Right Gastroepiploic (GV) and Pancreaticoduodenal Vein (PV). ​ Receives nutrient-rich blood from: ○​ Right gastroepiploic vein ​ Drains blood from the stomach ​ Runs along the greater curvature and provides most of the drainage to the superior mesenteric vein ​ Anastomoses with the left gastroepiploic vein → drains into Figure 25. Lymphatic drainage of the liver (Moore 9th ed.) splenic vein ​ Drain mainly to the hepatic nodes at the porta hepatis ○​ Pancreaticoduodenal Vein ​ From the hepatic nodes → celiac nodes → thoracic duct ​ Runs along the anterior curvature of the duodenum ○​ Lymph produced by the liver is collected mainly by efferent ​ Drains blood from the duodenum and pancreas lymphatic vessels from hepatic nodes ​ Course ○​ Proceeds to celiac lymph nodes ○​ Ascends close to the superior mesenteric artery ○​ Ends up in the thoracic duct ○​ Runs anterior to the ureter and uncinate process of the pancreas ​ Superficial lymphatics from the posterior aspect of the ○​ Dives deep to the neck of the pancreas, joining the splenic vein at diaphragmatic and visceral surfaces drain towards the bare area of L1 the liver ​ Drains the stomach, small intestine, pancreas, cecum, ascending ○​ Phrenic lymph nodes and transverse colons ○​ Posterior mediastinal lymph nodes OS 206 Stomach, Liver, Gallbladder 5 of 13  ○​ Restricts flow of blood and bile throughout the structures of the INNERVATION portal triad PORTAL HYPERTENSION ​ Hypertension localized ONLY to the portal system ​ Common causes: ○​ Liver cirrhosis ​ Caused by alcoholism and other liver diseases ○​ Blood clots ​ Clots in the portal vein increases BP in portal system ○​ Schistosomiasis ​ A parasitic disease ​ Impedes blood flow in the portal area, increasing BP ​ Affects anastomosis between the portal vasculature, resulting in vessel dilation and formation of varicose veins which may lead to potential fatal hemorrhage ​ Porto-systemic (Porto-caval) anastomosis: ○​ Collaboration between the portal and systemic venous system ○​ Includes: ​ Superior rectal and inferior rectal veins ​ Left gastric and esophageal veins q ​ Colonic veins and retroperitoneal veins Figure 26. Hepatic nervous plexus. ​ Paraumbilical and epigastric veins ​Most common site of Caput Medusa ​ Governed by the hepatic nervous plexus ​Caput Medusa: During portal hypertension, the vessels will ○​ Runs along the hepatic artery and portal vein enlarge and form large dilations and this will be seen under the ○​ The largest derivative of the celiac plexus skin and like snakes ○​ Consists of: ​ Sympathetic fibers from the celiac plexus ​ Parasympathetic fibers from the anterior and posterior vagal trunks ​ Nerve fibers accompany the vessels and biliary ducts of the portal triad ​ Function: Vasoconstriction ​ Purpose is still widely unknown G.​ BILIARY DUCTS RIGHT HEPATIC DUCT ​ Arises from the Right lobe of the liver ​ Drains bile from the Right functional lobe of the liver LEFT HEPATIC DUCT ​ Arises from the Left lobe of the liver ​ Drains bile from the Left functional lobe of the liver COMMON HEPATIC DUCT ​ Forms from the union of the Left and Right hepatic duct outside the Figure 28. Caput Medusa liver parenchyma LIVER BIOPSY CYSTIC DUCT ​ Commonly performed procedure to diagnose liver disease such as: ​ Drains bile from the gallbladder ○​ Nonalcoholic liver disease ​ A short duct into which the gallbladder opens ○​ Chronic hepatitis B or C ​ Contains the Spiral valves of Heister ○​ Autoimmune hepatitis ○​ Specialized ducts ○​ Liver cirrhosis ○​ DOES NOT resist flow going outside of the gallbladder ○​ Primary biliary cholangitis ○​ Results in bidirectional flow of bile ○​ Primary sclerosing cholangitis COMMON BILE DUCT ○​ Hemochromatosis ​ Forms from the union of the common hepatic duct and cystic duct ○​ Wilson’s disease ​ Passes into the greater duodenal papilla joined by the pancreatic duct, ​ Steps: forming the Ampulla of Vater ○​ Patient assumes Supine position ○​ Surrounded by the Sphincter of Oddi ○​ Patient is asked to hold breath in full expiration (maximum ○​ Helps regulate the release of bile into the small intestine expiration and hold) ○​ Opens/closes to allow bile and pancreatic juice to flow into the small ​ Decreases risk of lung damage intestine ○​ The needle is inserted into the 10th ICS near the midaxillary line ○​ The tissue may be sent to histopathology II.​ GALLBLADDER LEARNING OBJECTIVES At the end of the session, students are expected to know the ff: 1.​ Gross anatomy of the biliary ducts and gallbladder. 2.​Blood supply/drainage, lymphatics and nerve supply. 3.​Clinical correlation. ​ Length: 7 - 10 cm ​ Pear shaped ​ Can hold 50 mL of bile ​ Lies in the fossa for the gallbladder on the visceral surface of the liver ​ In its natural position, the body of the gallbladder lies anterior to the superior part of the duodenum, ​ Its neck and cystic duct are immediately superior to the duodenum ​ Filipino translation: apdo ​ Functions: ○​ Biliary duct conveys bile from liver to duodenum ○​ Bile is continuously produced in the liver, then stored and concentrated in the gallbladder ○​ Gallbladder releases bile intermittently when fat enters the duodenum ○​ Bile emulsifies fat so it can be absorbed in the distal intestine ​ Why people with gallstones have right upper epigastric pain when Figure 27. Biliary tract: Right & Left Hepatic Ducts, Common hepatic duct, Cystic eating fatty food: gallstones block pathway of bile into duodenum duct, Common bile duct, Hepatopancreatic ampulla (Ampulla of Vater) (Moore, 2023) H.​ CLINICAL CORRELATES PRINGLE MANEUVER ​ Technique used during some trauma involving the liver ​ Steps: ○​ Clamp the hepatoduodenal ligament without dissecting any structures OS 206 Stomach, Liver, Gallbladder 6 of 13  A.​ PARTS OF THE GALLBLADDER Figure 29. Parts of the gallbladder. ​ Fundus ○​ Adjacent to the anterior abdominal wall ○​ Behind the 8th costal cartilage on the right side of the body ○​ Enlargement will cause projection from the liver[2027 Trans] ​ Body ○​ Corpus vesicae biliaris ○​ Largest part ○​ Found at the inferior surface of the liver ​ Infundibulum ○​ Hartmann’s pouch ○​ Tapering area between the body and the neck of gallbladder ○​ Communicates bile from body to the neck[2027 Trans] Figure 31. Lymphatic drainage of the gallbladder. ​ Neck NERVES ○​ Collum vesicae biliaris ○​ Most proximal and narrow part ​ Parasympathetic stimulation causes contraction of the gallbladder ○​ Its folds give it a twisted shape and relaxation of the sphincters at the hepatopancreatic ampulla ​ Cystic duct ​ Generally stimulated by cholecystokinin (CCK) which is produced by ○​ Ductus cysticus duodenal walls especially in the presence of fats, i.e., after eating a fatty ○​ Convey bile from gallbladder to bile duct and vice versa meal ○​ 3-4 cm in length ​ The nerves to the gallbladder and cystic duct pass along the cystic ○​ Has 5-12 folds giving it its twisted shape artery from the[2027 Trans]: ○​ Has spiral valves to distend duct[2027 Trans] ○​ Celiac nerve plexus ​ Do not provide resistance to flow of bile, allowing bile to travel ​ Sympathetic bidirectionally ​ Visceral afferent (pain) fibers ○​ Joins common hepatic duct to become the common bile duct ○​ Vagus nerve ​ Ampulla of Vater ​ Parasympathetic ○​ Opening of duodenum where pancreatic duct and bile duct release ○​ R Phrenic nerve their secretions ​ Somatic afferent fibers ○​ Bounded by sphincter of duodenum B.​ NEUROVASCULATURE ARTERIAL SUPPLY ​ Supplied primarily by the cystic artery arising from the R hepatic artery into the cystohepatic triangle (triangle of Calot) ○​ Bounded by: ​ Inferior: cystic duct ​ Medial: common hepatic duct ​ Superior: visceral surface of liver ​ Also supplied by posterior superior pancreaticoduodenal artery and the gastroduodenal arteries ​ 24.5% of patients have a cystic duct that has a different path Figure 30. Anatomical variants of gallbladder arterial supply. VENOUS DRAINAGE Figure 32. Nerves of the gallbladder. ​ Cystic vein C.​ CLINICAL CORRELATES ○​ Receives the venous drainage from the neck of the gallbladder and cystic duct GALLBLADDER STONES ​ Hepatic sinusoids ​ Also known as cholelith ○​ Drains the veins from the fundus and body of the gallbladder which ○​ Filipino translation: Mga bato sa apdo pass directly into the visceral surface of the liver ​ Hardened deposits of bile and calcium salts ​ Posterior superior pancreaticoduodenal vein ​ Form primarily due to oversaturation: ○​ Drains distal bile duct ○​ Bile contains too much cholesterol LYMPHATIC DRAINAGE ○​ Bile contains too much bilirubin ○​ Gallbladder does not empty correctly ​ The lymphatic drainage of the gallbladder is to: ​ Typically cause no symptoms when staying in the bile duct ○​ Hepatic lymph nodes ○​ 70% of people with gallstone remain asymptomatic ○​ Cystic lymph nodes ​ Some develop just one gallstone, while other develop many gallstones ​ Located near the neck of the gallbladder[2027 Trans] at the same time ○​ Celiac lymph nodes ​ Range in size from as small as a grain[2027 Trans] ​ Receive lymph from efferent lymphatic vessels of the cystic and ​ May block the neck or cystic duct that drains bile from the gallbladder, lymphatic lymph nodes[2027 Trans] resulting in cholecystitis, which is the redness and inflammation of the gallbladder ○​ Risk of bacterial infection due to the obstruction of the flow of the bile outside the gallbladder ○​ Symptoms include upper right quadrant pain or fever ○​ Can be treated with antibiotics or pain relievers, however if the pain is recurring, it is advised that the patient undergo surgery, known as cholecystectomy, which involves the removal of the gallbladder ​ May block the common bile duct, resulting in choledocholithiasis OS 206 Stomach, Liver, Gallbladder 7 of 13  ○​ Results in jaundice and liver damage ​ Diagnosed by use of Ultrasound or Endoscopic Retrograde B.​ PARTS OF THE STOMACH Cholangiopancreatography (ERCP) ​ Divided into four parts: Cardia, Fundus, Body, Pyloric parts ​ Types of Gallstones[2027 Trans] ○​ Cholesterol gallstones ​ Most common type of gallstone ​ Appears yellow in color ​ Composed mainly of undissolved cholesterol, but may contain other components ○​ Pigment gallstones ​ Appears dark brown or black ​ When bile contains too much bilirubin Figure 36. Parts of the stomach CARDIA ​ Surrounds the cardiac orifice ​ Cardiac orifice ○​ Opening of the stomach Figure 33. Cholesterol and pigment gallstones. ○​ Supine position: III.​ STOMACH ​ Posterior to the 6th left costal cartilage ​ 2-4 cm from the median plane at the level of T11 vertebra LEARNING OBJECTIVES At the end of the session, students are expected to know the ff: FUNDUS 1.​ Gross anatomy of the stomach. ​ Dilated superior part that is related to the left dome of the 2.​Blood supply/drainage, lymphatics and nerve supply. diaphragm 3.​Clinical correlation. ​ Limited by the horizontal plane of the cardiac orifice ​ Filipino translation: Sikmura ​ Cardiac notch ​ Expandable part of the digestive tract ○​ Found between the esophagus and fundus ○​ Can hold 2-3L of food ​ May be dilated by gas, fluid, food, or any combination ​ Between the esophagus and the small intestine ​ Supine position: ​ Specialized for accumulation of food ○​ Posterior to the 6th left rib in the plane of the midclavicular line ○​ Prepares the food for digestion and passage into the duodenum BODY ○​ Acts as a food blender and reservoir ​ Chief function: Enzymatic digestion ​ Major part of the stomach ○​ Produces gastric juice ​ Located between the fundus and pyloric antrum ​ Converts food into chyme PYLORIC PART ​ An empty stomach is only slightly larger in caliber than the large ​ Funnel-shaped outflow of the stomach intestine ​ Divided into two: A.​ POSITION OF THE STOMACH ○​ Pyloric antrum ​ Wider part ​ Leads into the pyloric canal ○​ Pyloric canal ​ Narrower part ​ Pylorus ○​ Distinct sphincter region ○​ Outlet (inferior opening) of the stomach ○​ Marked thickening of the circular layer of the smooth muscle ○​ Controls discharge of the stomach contents through the pyloric orifice into the duodenum ​ Supine position: ○​ Lies at the level of the transpyloric plane ​ Transpyloric plane ○​ Midway between the jugular notch (superiorly) and pubic crest (inferiorly) ○​ Transects the 8th costal cartilages and the L1 vertebra CURVATURES Figure 34. Anterior view of the abdomen in supine position ​ Lesser curvature ​ Supine position ○​ Forms the shorter concave right border of the stomach ○​ Lies in the right and left upper quadrants ○​ Angular incisure (notch) ○​ Occupies the epigastric, umbilical, left hypochondrium, and flank ​ Most inferior part of the curvature region ​ Indicates the junction of the body and pyloric part of the ​ Standing position stomach ○​ Stomach moves inferiorly ​ Left of midline ​ Position of the stomach depends on the body’s build ​ Greater curvature ○​ Heavier build ○​ Forms the longer convex left border of the stomach ​ Located high and more transversely disposed C.​ INTERIOR OF THE STOMACH ​ More prone to acid reflux ○​ Slender build ​ Located low and more vertical Figure 37. Anterior view of the interior of the stomach Figure 35. Difference in the position and shape of the stomach in individuals with a heavier build (left) and individuals with a slender build (right) ​ Smooth surface of gastric mucosa OS 206 Stomach, Liver, Gallbladder 8 of 13  ○​ Reddish brown in life ○​ Brown in cadavers ​ Covered by a continuous mucus layer ○​ Protection of the surface from gastric acid ​ Gastric folds (gastric rugae) ○​ Seen when the stomach contracts ○​ Most appreciated toward the pyloric part and along the greater curvature ○​ Folds are diminished in distended or filled stomach ​ Gastric canal ○​ Formed by the firm attachment of the gastric mucosa to the muscular layer ○​ Saliva and small quantities of masticated food drain along the gastric canal to the pyloric canal when the stomach is mostly empty D.​ RELATION OF THE STOMACH Figure 40. Arterial supply of the stomach. ​ Celiac trunk has arterial branches that anastomose and supply different areas of the stomach: Table 3. CELIAC TRUNK BRANCHES AND ARTERIAL SUPPLIES ARTERY SUPPLIES: RIght and Left Gastric Arteries Lesser curvature Right and Left Gastro-omental Greater curvature Arteries Short arteries and Posterior Fundus and Upper body gastric arteries VENOUS DRAINAGE Figure 38. Anterior view of the abdomen showing the structures surrounding the stomach. ​ Anteriorly ○​ Diaphragm ○​ Left lobe of the liver ○​ Anterior abdominal wall ​ Posteriorly Figure 41. Venous drainage of the stomach. ○​ Omental bursa ○​ Pancreas ​ Veins that drain the stomach include the following: ○​ Posterior surface of the stomach ○​ Right and left gastric veins ​ Forms most of the anterior wall of the omental bursa ○​ Short gastric veins ​ Inferiorly and laterally ○​ Left gastro-omental veins ○​ Transverse colon ○​ Splenic vein ​ Courses along the curvature of the stomach to the left colic ○​ Right gastro-omental vein flexure ○​ Prepyloric vein ○​ Right gastric vein ​ They follow the nomenclature of the arteries very closely ​ Ultimately, these veins drain into three large vessels: ○​ Hepatic portal vein ○​ Splenic vein ○​ Superior mesenteric veins Table 4. VENOUS DRAINAGE SYSTEM OF STOMACH (Batch 2028) DRAINAGE VEINS ​ Right gastric vein Hepatic portal vein ​ Left gastric vein ​ Short gastric veins Splenic vein ​ Left gastro-omental vein Superior mesenteric veins ​ Right gastro-omental vein Figure 39. Bed of the stomach LYMPHATIC DRAINAGE ​ Bed of the stomach ○​ Where the stomach rests in supine position ○​ Formed by the structures forming the posterior wall of the omental bursa ○​ Structures from superior to inferior: Left dome of the diaphragm → Spleen → Left kidney and suprarenal gland → Splenic artery → Pancreas → Transverse mesocolon E.​ NEUROVASCULATURE OF THE STOMACH ARTERIAL SUPPLY Figure 42. Lymphatics of the stomach OS 206 Stomach, Liver, Gallbladder 9 of 13 ​ Lymph is drained into different lymph nodes (LN) depending on the region of the stomach Table 5. LYMPHATIC DRAINAGE SYSTEM OF STOMACH LYMPH FROM RECEIVED BY Superior 2/3 of stomach Gastric LN Fundus and superior part of body Pancreaticosplenic LN Right inferior 2/3 of stomach Pyloric LN Left 1/3 of greater curvature Pancreatico-duodenal LN NOTE: Neural innervation was deliberately omitted by Doc Dumlao during the lecture, hence the following is referenced from Batch 2028 Trans: Figure 44. Dissection of the upper peritoneal cavity. NEURAL INNERVATION Figure 45. Falciform ligament. Figure 43. Innervation of the stomach. Table 6. INNERVATIONS OF THE STOMACH INNERVATION SUPPLIES FUNCTION ​ Anterior surface of Anterior vagal ​ Inducing gastric stomach trunk secretion ​ Pylorus Parasym- ​ Relaxation of pathetic ​ Remaining anterior pyloric sphincter Posterior vagal surface during gastric trunk ​ Entire posterior emptying Figure 46. Parts of the stomach. surface ​ Inhibiting gastric motility Sympa- ​ Constricting the Celiac plexus thetic pyloric sphincter preventing gastric emptying ​ Sensation of pain, Visceral Vagus nerves fullness and afferent nausea F.​ CLINICAL CORRELATES GASTRITIS Figure 47. Liver and gallbladder. ​ Inflammation of stomach lining ○​ In Filipino, sinisikmura or humahapdi ang tiyan B.​ PART 2: THE LEFT SIDE OF THE PERITONEAL CAVITY ​ Causes: ​ When we go to the left side, there is abundant fatty omentum ○​ Bacterial infection hanging from the greater curvature and the transverse colon ○​ Regular use of certain pain relievers ​ When we pull away some of the redundant fatty omentum, we can ○​ Alcohol intake get a clearer look at the spleen ○​ Stress ​ Stomach produces more gastric acid ​ Symptoms: ○​ Gnawing or burning ache or pain (indigestion) in your upper abdomen that may become worse or better with eating ○​ Nausea ○​ Vomiting ○​ Feeling of fullness in your upper abdomen after eating IV.​ DISSECTION VIDEOS A.​ PART 1: UPPER REGION OF THE PERITONEAL CAVITY Figure 48. Redundant fatty omentum. OS 206 Stomach, Liver, Gallbladder 10 of 13  Figure 53. Common hepatic artery Figure 49. Spleen. ​ In many cases, the liver is enlarged in most cadavers ​ When we stretch out the stomach, we can see a small, fatty-filled mesentery → This is the hepatogastric ligament, which comprises the lesser omentum with the thicker hepatoduodenal ligament Figure 54. Proper hepatic artery Figure 50. Hepatogastric ligament. Figure 55. Gastroduodenal artery Figure 51. Hepatoduodenal ligament. C.​ PART 3: EPIPLOIC FORAMEN ​ Immediately posterior to the hepatoduodenal ligament is the epiploic foramen Figure 56.Thin right gastric artery held by forceps. ​ The junction of the common hepatic artery arises from the celiac artery and gives rise to the proper hepatic artery ​ Identify the gastroduodenal artery at the level of the pyloric region or the junction of the gastric stomach to the first part of the Figure 52. Finger going through the epiploic foramen. duodenum ​ Immediately posterior to the hepatoduodenal ligament is the epiploic foramen ​ When a finger is inserted into the epiploic foramen, you may bring the finger to touch the very thin lesser omentum and the ligaments that comprise it ○​ The hepatoduodenal ligament has a very thick consistency due to the tubular structure inside it D.​ PART 4: PROPER HEPATIC ARTERY ​ Remove the serous membranes that comprise or surround the structures that surround the hepatoduodenal ligament ​ Scratch through the top surface to take away the connective tissues to identify structures wrapped by the hepatoduodenal ligament: ○​ Common bile duct ○​ Proper hepatic artery Figure 57. Collapsed bile duct. ○​ Portal vein ​ In the inferior free edge is the wide but collapsed common bile duct E.​ PART 5: COMMON BILE DUCT OS 206 Stomach, Liver, Gallbladder 11 of 13 ​ The cystic duct drains into the common bile duct ○​ This represents the obliterated left umbilical vein ​ The large duct above is the common hepatic duct ​ The junction of the common hepatic duct and the cystic duct forms the beginning of the common bile duct ​ Triangle of Calot: triangular space between the common hepatic duct, the cystic duct, and the surface of the liver ○​ 90% of the time, the cystic artery crosses this triangle ○​ There are other anatomical variations to its course Figure 62. Ligamentum teres hepatitis ​ Different impressions are produced by the viscera that are related to the liver: Figure 58. Liver and gallbladder. ○​ Gastric impression F.​ PART 6: OTHER NEUROVASCULATURE ○​ Duodenal impression ​ The portal vein is very wide and broad ○​ Right colic flexure ​ It is the most posterior structure to the hepatoduodenal ligament ○​ Renal impression (right kidney) ○​ Right suprarenal gland ​ In the same visceral side, you can see an H-shaped arrangement: ○​ The vertical bar is formed by the: fissure for ligamentum teres and the fissure for ligamentum venosum ​ On the right side: ○​ The upper bar is formed by the inferior vena cana ​ Grooves the liver and by the gallbladder ​ Horizontal bar is formed by the porta hepatitis ○​ Structures pass in and out of the liver ​ Gall bladder attached to the visceral surface ○​ Has a fundus, body, and, neck, leading to the cystic duct ​ There is a portal vein passing through the porto hepatitis Figure 59. The finger in the lesser sac. ​ The celiac trunk has the following branches: ○​ left gastric ○​ splenic ○​ common hepatic arteries Figure 63. Portal vein ​ The falciform ligament will split into two as it approaches the liver Figure 60. The finger in the lesser sac. G.​ CADAVER LIVER ​ The liver has a diaphragmatic surface and visceral surface ​ Has 2 lobes: ○​ Right and left ​ Demarcation of the two lobes is the attachment of the Falciform ligament Figure 64. Falciform ligament separating into right and left. ​ The left will fold around itself forming the left triangular ligament ○​ Attaches left lobe of ligament to the diaphragm Figure 61. Falciform ligament. ​ Thickening below the falciform ligament is the ligamentum teres Figure 65. Left Triangular ligament hepatis ​ On the right side, anterior coronary ligament is formed OS 206 Stomach, Liver, Gallbladder 12 of 13  ○​ Largely formed by a wide area not covered by the peritoneum Figure 68. Caudate lobe (bare area of the liver). ○​ Quadrate lobe ​ Below the porta hepatitis ​ Quadrangular shape ​ Between fissure of ligamentum teres and groove lodging gallbladder ○​ The lobes function as left part of the liver ​ Anatomically, they belong to the right Figure 66. Coronary Ligament. ​ The inferior vena cava grooves the liver ○​ Pierces upward to pass through the central tendon of the diaphragm Figure 69. Quadrate lobe V.​ REFERENCES AND CITATION Moore, K. L., Dalley, A. F., & Agur, A. (2023). Clinically oriented anatomy (9th ed.). Lippincott Williams and Wilkins. Netter, F. H. (2023). Netter atlas of human anatomy classic regional approach (9th ed.) UPCM 2028 Trans. (2024). Stomach, liver, gallbladder. UPCM 2027 Trans. (2023). Stomach, liver, gallbladder. Figure 67. Hepatic veins ​ Hepatic veins drain into the ○​ Inferior vena cava as it grooves the liver ​ In the visceral surface of the liver, there are two lobes: ○​ Caudate lobe ​ Located between the groove for the IVC and fissure for ligamentum venosum ​ Cephalic position ​ Called caudate due to the process or tail called caudate process ​ Above porta hepatis OS 206 Stomach, Liver, Gallbladder 13 of 13