Week 10 & 11 - Abdominal Cavity, Peritoneum & Gastrointestinal Tract Flashcards
* Define parietal & visceral peritoneum and explain the functions of the peritoneum & peritoneum cavity * Draw diagrams to explain different relationships to the peritoneum (mesenteries & retroperitoneal positions) and list the structures contained within a typical mesentery * Describe the boundaries of the lesser sac and of the epiploic foramen (on Winslow) * Demarcate the course and distribution of arteries to important structures or organs derived from the foregut, midgut and hindgut
What is the function of the liver?
The liver performs various functions including:
* Detoxification
* Metabolism
* Production of biochemicals necessary for digestion
Which arteries is responsible for supplying the stomach?
Lesser Curvature
Left & Right gastric arteries
Greater Curvature
Left & Right gastro-omental arteries
Which artery supplies blood to the spleen?
Splenic artery
What is the role of the gastroduodenal artery?
It supplies blood to the stomach and the duodenum.
Which artery supplies the greater curvature of the stomach?
Right gastro-omental artery
What does the superior mesenteric artery supply?
It supplies the midgut.
Name the artery that supplies the duodenum.
Duodenal artery
What does the middle colic artery supply?
It supplies the transverse colon.
Which artery supplies the ascending colon?
Right colic artery
What artery supplies the cecum and appendix?
Ileocolic artery
What is the anatomical position of the small intestine in the anterior view?
Located below the stomach and above the colon.
What artery is associated with the thoracic aorta?
Anterior view of the thoracic aorta.
Which artery is part of the celiac trunk?
Left gastric artery
What does the inferior mesenteric artery supply?
It supplies the hindgut.
What is the major vein draining the gallbladder?
Cystic vein
Which vein drains directly into the hepatic portal vein?
Right gastric vein
What is the function of the pancreaticoduodenal veins?
They drain the pancreas and duodenum.
Which vein drains the middle colic area?
Middle colic vein
What is the role of the appendicular vein?
It drains the appendix.
True or False: The esophageal branch is part of the azygos venous system.
True
What structure is known as the cardial notch?
The superior angle where the left margin of the oesophagus joins the greater curvature of the stomach
An anatomical feature of the stomach.
Which vein drains the spleen?
Splenic vein
What are the veins that drain the greater curvature of the stomach?
Left and right gastro-omental veins
What does the inferior mesenteric vein drain?
It drains the hindgut.
What is the role of the superior mesenteric vein?
It drains the midgut.
Fill in the blank: The _______ veins drain the left colic area.
Left colic
What veins are associated with the jejunum and ileum?
Jejunal and ileal veins
Which veins drain the sigmoid colon?
Sigmoid veins
What is the role of the superior rectal veins?
They drain the rectum.
What is the origin of the celiac trunk?
Abdominal aorta (at level of aortic hiatus)
The celiac trunk is a major artery supplying the abdominal organs.
What does the coeliac trunk trifurcate into?
- Left Gastric
- Splenic
- Common hepatic arteries
Which organs are supplied by the celiac trunk?
- Esophagus
- Stomach
- Proximal duodenum
- Liver/biliary apparatus
- Pancreas
The celiac trunk is crucial for supplying blood to the upper abdominal organs.
What is the course of the left gastric artery?
Ascends retroperitoneally to the esophageal hiatus, then descends along lesser curvature
It gives rise to an esophageal branch.
What does the left gastric artery anastomose with?
Right gastric artery
This anastomosis ensures adequate blood supply to the stomach.
Which organs are supplied by the splenic artery?
- Body of pancreas
- Spleen
- Greater curvature and posterior stomach body
The splenic artery runs along the superior border of the pancreas.
Where does the posterior gastric artery originate?
Or Short Gastric arteries
From the splenic artery posterior to the stomach
It ascends retroperitoneally along the posterior wall of the lesser omental bursa.
What is the distribution area of the left gastro-omental artery?
Left portion of greater curvature of the stomach
It anastomoses with the right gastro-omental artery.
How many short gastric arteries typically arise?
4–5
These arteries supply the fundus of the stomach.
What is the origin of the hepatic artery?
Celiac trunk
It supplies several organs including the liver and gallbladder.
What does the hepatic artery bifurcate into?
Right and left hepatic arteries
These arteries supply the liver.
What is the course of the cystic artery?
Arises within hepatoduodenal ligament
It supplies the gallbladder and cystic duct.
What does the right gastric artery anastomose with?
Left gastric artery
It runs along the lesser curvature of the stomach.
What areas does the gastroduodenal artery supply?
- Stomach
- Pancreas
- First part of duodenum
- Distal part of bile duct
It descends retroperitoneally, posterior to the gastroduodenal junction.
What is the distribution area of the right gastro-omental artery?
Right portion of greater curvature of stomach
It anastomoses with the left gastro-omental artery.
What does the superior pancreaticoduodenal artery supply?
- Proximal portion of duodenum
- Superior part of head of pancreas
It divides into anterior and posterior arteries on each side of the pancreatic head.
What is the origin of the inferior pancreaticoduodenal artery?
Superior mesenteric artery
It supplies the distal portion of the duodenum and head of pancreas.
Fill in the blank: The left gastro-omental artery passes between layers of the _______ to supply the stomach.
[gastrosplenic ligament]
It is important for the blood supply of the greater curvature of the stomach.
What is the left gastric vein?
A vein that drains blood from the stomach to the portal vein.
It is part of the venous drainage of the stomach.
What does the right gastric vein do?
Drains blood from the stomach to the portal vein.
It is involved in the venous return from the stomach.
What is the function of the short gastric vein?
Drains blood from the fundus of the stomach to the splenic vein.
It connects to the splenic vein, which is part of the portal circulation.
What is the portal vein?
A major vein that carries blood from the gastrointestinal tract and spleen to the liver.
It plays a crucial role in directing blood flow from the digestive organs to the liver for processing.
What is the prepyloric vein?
Vein that drains blood from the pylorus region of the stomach.
It is involved in the venous drainage of the pyloric area.
What is the pylorus?
The region of the stomach that connects to the duodenum.
It acts as a valve to control the passage of food into the small intestine.
What are pancreaticoduodenal veins?
Veins that drain the pancreas and duodenum into the portal vein.
They play a role in the venous drainage of the pancreas and the first part of the small intestine.
What is the posterior gastric vein?
A vein that drains blood from the posterior aspect of the stomach.
It typically drains into the splenic vein.
What is the left gastro-omental vein?
Vein that drains blood from the greater curvature of the stomach.
It connects to the splenic vein and is involved in gastric drainage.
What is the splenic vein?
A vein that drains blood from the spleen to the portal vein.
It is a significant component of the portal venous system.
What does the right gastro-omental vein do?
Drains blood from the greater curvature of the stomach into the superior mesenteric vein.
It is important for the venous return from the stomach.
What is the inferior mesenteric vein?
A vein that drains blood from the lower gastrointestinal tract into the splenic vein.
It collects blood from the descending colon, sigmoid colon, and rectum.
What is the superior mesenteric vein?
A vein that drains blood from the small intestine and parts of the colon into the portal vein.
It is vital for the venous drainage of the upper gastrointestinal tract.
What can be seen from an anterior view?
Structures of the stomach and related veins.
The anterior view provides insight into the anatomy of the stomach’s blood supply.
What is the anatomical structure associated with the right side of the thoracic sympathetic trunk?
Right thoracic sympathetic trunk
What nerve is referred to as becoming the posterior vagal trunk?
Right vagus nerve
What does the left vagus nerve become?
Anterior vagal trunk
What type of plexus is associated with the esophagus?
Esophageal (nerve) plexus
Which lymph nodes are located in the celiac region?
Celiac lymph nodes
Which lymph nodes are specifically named for the left gastric area?
Left gastric lymph nodes
What are the two types of splanchnic nerves mentioned?
- Greater splanchnic
- Lesser splanchnic
What is the collective term for the celiac plexus and its associated ganglia?
Celiac plexus and ganglia
What type of plexus surrounds the left gastric artery?
Per-arterial plexus of nerves
What are the branches of the vagus nerve that supply the stomach?
- Posterior gastric branches
- Anterior gastric branches
- Pyloric branches of vagus nerve
What is the anatomical location of the right dome of diaphragm?
Located above the liver
The right dome of the diaphragm is the superior part of the diaphragm on the right side.
Which organ is located under the right dome of the diaphragm?
Liver
The liver is a large organ responsible for various metabolic processes.
What is the function of the fundus of the gallbladder?
Stores bile
The fundus is the rounded, upper portion of the gallbladder.
Where is the pylorus located in relation to the stomach?
At the distal end of the stomach
The pylorus connects the stomach to the duodenum.
What is the outline of the duodenum?
The first part of the small intestine
The duodenum is responsible for the initial phase of digestion.
What is the anatomical position of the ascending colon?
Located on the right side of the abdomen
The ascending colon is part of the large intestine.
What structure is referred to as the cecum?
The beginning of the large intestine
The cecum is located at the junction of the small and large intestines.
What landmark is indicated by the anterior superior iliac spine?
A bony prominence on the pelvis
It serves as an important anatomical reference point.
What can be seen in the anterior view of the abdomen?
Scapula, left dome of diaphragm, outline of stomach
These structures are visible from the front view of the body.
What is located in the posterior view of the abdomen?
Apex of heart, spleen, outline of pancreas
The posterior view reveals organs located towards the back of the body.
What is the function of the small intestine?
Digestion and absorption of nutrients
The small intestine consists of the jejunum and ileum.
Fill in the blank: The _______ colon is located on the left side of the abdomen.
Descending
The descending colon is part of the large intestine.
What is the anatomical significance of the sigmoid colon?
Prepares waste for elimination
The sigmoid colon is the last section of the colon before the rectum.
What does the urinary bladder do?
Stores urine
It is a muscular sac that collects urine from the kidneys.
Which organ is located behind the stomach?
Pancreas
The pancreas plays a crucial role in digestion and blood sugar regulation.
True or False: The esophagus connects the throat to the stomach.
True
The esophagus is a muscular tube that transports food.
What is the role of the right suprarenal gland?
Produces hormones like adrenaline
The suprarenal glands are also known as adrenal glands.
What organ is primarily responsible for filtering blood?
Kidney
The kidneys also regulate fluid balance and electrolytes.
Fill in the blank: The _______ is the pouch that stores bile.
Gallbladder
The gallbladder releases bile into the small intestine to aid digestion.
What is the role of the appendix?
May play a role in immune function
The appendix is often considered a vestigial organ.
Where is the rectum located?
At the end of the large intestine
The rectum stores feces until elimination.
What are the primary functions of the liver?
Synthesis of bile, glycogen storage, clotting factor production
The liver plays a crucial role in digestion and metabolism.
What structures are in direct contact with the liver?
Right kidney, right adrenal gland, right colic flexure, transverse colon, first part of the duodenum, gallbladder, oesophagus, stomach
These structures are essential for understanding liver anatomy.
What is the role of the falciform ligament?
Divides the left and right lobes of the liver
It also contains the ligamentum teres, a remnant of the umbilical vein.
What does the lesser omentum connect?
Liver to the lesser curvature of the stomach and first part of the duodenum
It consists of the hepatoduodenal and hepatogastric ligaments.
What are hepatic recesses?
Subphrenic spaces and subhepatic space
These peritoneal spaces are important for understanding liver pathology.
What is the dual blood supply of the liver?
Hepatic artery proper (25%) and hepatic portal vein (75%)
The hepatic portal vein carries partially deoxygenated blood.
What are the stages of alcohol-induced liver damage?
Fatty liver, fibrosis, cirrhosis
These stages reflect the progression of liver disease.
What are common causes of jaundice?
Pre-hepatic, hepatic, post-hepatic obstructions
Conditions like gallstones, malignancy, and infections can lead to jaundice.
What are the symptoms of jaundice?
Dark urine, light stools, yellow skin, itch, vomiting, anorexia, weight loss, abdominal pains
These symptoms indicate liver dysfunction or bile duct obstruction.
What imaging modalities are used for liver and biliary tree assessment?
Ultrasound, MRI, CT, MRCP, ERCP
Each modality has its advantages and limitations.
What is ascites?
Accumulation of protein-containing fluid within the abdomen
Often caused by portal hypertension.
What is colitis?
Inflammation of the inner lining of the colon
Causes include infection and inflammatory bowel diseases like Crohn’s disease.
What are the complications associated with peptic ulcer disease?
Haemorrhage, perforation, stenosis
These complications can arise from gastric or duodenal ulcers.
Fill in the blank: The __________ is a remnant of the umbilical vein.
ligamentum teres
It is located at the free edge of the falciform ligament.
True or False: The left triangular ligament attaches the right lobe of the liver to the diaphragm.
False
The left triangular ligament attaches the left lobe of the liver to the diaphragm.
What is the primary blood supply to the liver?
Hepatic artery and hepatic portal vein
The hepatic artery supplies oxygen-rich blood, while the portal vein supplies nutrient-rich blood from the digestive tract.
What are the two main types of gallstones?
Cholesterol stones and pigment stones
Cholesterol stones make up 80% of gallstones.
What does the term ‘biliary colic’ refer to?
Pain caused by gallstones blocking the bile ducts
This condition can lead to cholecystitis if not treated.
What is the peritoneum?
A continuous membrane that lines the abdominal cavity and supports the viscera
It provides pathways for blood vessels and lymph to travel to and from the viscera.
What are the two layers of the peritoneum?
Parietal peritoneum and visceral peritoneum
Both layers are made of simple squamous epithelial cells.
What does the parietal peritoneum line?
The internal surface of the abdominopelvic wall
It has a somatic nerve supply for well-localized pain.
What type of nerve supply does the visceral peritoneum have?
Autonomic nerve supply
It is poorly localized and refers pain to dermatomes.
Which organs are classified as intraperitoneal organs?
- Stomach
- Liver
- Spleen
- Tail of the pancreas
- Jejunum
- Ileum
- Cecum
- Appendix
- Transverse colon
- Sigmoid colon
Intraperitoneal organs are covered anteriorly and posteriorly by visceral peritoneum.
What does SAD PUCKER stand for in relation to extraperitoneal organs?
- S → Suprarenal gland
- A → Aorta/IVC
- D → Duodenum (prox. 2cm)
- P → Pancreas (excl. tail)
- U → Ureters
- C → Colon (ascending/descending)
- K → Kidneys
- E → (O)esophagus
- R → Rectum
Extraperitoneal organs are covered only anteriorly.
What is the function of the mesentery?
Connects intraperitoneal organs to the posterior wall
It is a double-layered visceral peritoneum.
What is the greater omentum?
A sheet of visceral peritoneum that descends from the greater curvature and proximal duodenum
It has 4 layers and attaches to the anterior transverse colon.
What is the lesser omentum?
A sheet of visceral peritoneum that attaches from the lesser curvature of the stomach and proximal duodenum to the liver
It has 2 layers and contains the hepatogastric and hepatoduodenal ligaments.
Which regions correspond to referred pain from foregut, midgut, and hindgut structures?
- Foregut structures → epigastric region
- Midgut structures → umbilicus region
- Hindgut structures → pubic region
This classification helps in diagnosing the source of abdominal pain.
What organs are classified as foregut structures?
- Oesophagus
- Stomach
- Pancreas
- Liver
- Gallbladder
- Duodenum (prox. to common bile duct)
These structures are involved in the early stages of digestion.
What organs are classified as midgut structures?
- Duodenum (distal to common bile duct)
- Proximal 2/3 of transverse colon
Midgut structures are responsible for the absorption of nutrients.
What organs are classified as hindgut structures?
- Distal 1/3 of transverse colon
- Anal canal
Hindgut structures are involved in the formation and elimination of waste.
What are the subdivisions of the peritoneal cavity?
- Greater sac
- Lesser sac
The greater sac is further divided into supracolic and infracolic compartments.
What does the greater sac contain?
- Supracolic compartment: stomach, liver, spleen
- Infracolic compartment: small intestine, ascending and descending colons
The compartments are connected by paracolic gutters.
What is located posterior to the stomach and lesser omentum?
The lesser sac
It is connected to the greater sac via the epiploic foramen.
What are the boundaries of the epiploic foramen?
- Anterior: hepatoduodenal ligament containing the portal triad
- Posterior: IVC and right crus of diaphragm
- Superior: liver
- Inferior: 1st part of duodenum
This foramen connects the greater and lesser sacs.
Where is the liver primarily located?
R upper quadrant, under right costal margin & hemidiaphragm, extends to left hemidiaphragm
What are the two surfaces of the liver?
- Diaphragmatic surface (anterosuperior)
- Visceral surface (posteroinferior)
What is the characteristic of the diaphragmatic surface of the liver?
Smooth, convex, NOT covered by visceral peritoneum
What structures does the visceral surface of the liver come into contact with?
- Abdominal part of esophagus
- Fundus of stomach
- 1st part of duodenum
- Right colic flexure & transverse colon
- Right kidney & adrenal gland
- Gallbladder
- IVC
What is the function of the falciform ligament?
Attaches anterior surface of liver to anterior abdominal wall at umbilicus
What does the coronary ligament demarcate?
Demarcates the bare area of the liver
What are the components of the lesser omentum?
- Hepatoduodenal ligament
- Hepatogastric ligament
What are the peritoneal recesses associated with the liver?
- Subphrenic
- Subhepatic
- Morison’s
What surrounds the liver and provides structural support?
Glisson’s capsule
What is the primary blood supply to the liver?
- Hepatic artery proper (25%)
- Hepatic portal vein (75%)
What is the function of the hepatic portal vein?
Carries partially deoxygenated blood and nutrients from the abdominal part of the GI tract
What structures are drained by the hepatic veins?
- Right hepatic vein
- Left hepatic vein
- Middle hepatic vein
True or False: The hepatic portal vein has valves.
False
What is the anatomical position of the pancreas?
Level of transpyloric plane (L1), with the tail being retroperitoneal
What connects the head of the pancreas to the duodenum?
Connective tissue
What are the two types of pancreas?
- Endocrine pancreas (islets of Langerhans)
- Exocrine pancreas (digestive enzymes)
What is the cause of pancreatitis represented by the acronym GET SMASHED?
- Gallstones
- Ethanol
- Trauma
- Steroids
- Mumps
- Autoimmune
- Scorpion Stings
- Hypertriglyceridemia, hypercalcemia, and hyperparathyroidism
- ERCP
- Drugs (sodium valproate, azathioprine)
What is the anatomical position of the spleen?
Upper left quadrant, below left ribs 9-11
What is the arterial supply to the spleen?
Splenic artery (arising from coeliac trunk)
What is the venous drainage of the spleen?
Splenic vein combines with superior mesenteric vein to form hepatic portal vein
What lymph nodes are involved in the lymphatic drainage of the spleen?
Pancreaticosplenic nodes and coeliac nodes
Fill in the blank: The gallbladder is _____ to the liver.
Inferior
What is the main duct system of the pancreas?
Main pancreatic duct runs the length of the pancreas and joins with the common bile duct
What is the function of cholecystokinin in relation to the gallbladder?
Mediates contraction of gallbladder and secretion of bile
What anatomical structures are connected by the gastrosplenic ligament?
Spleen to greater curvature of stomach
What is the role of the sphincter of Oddi?
Regulates the flow of bile and pancreatic juice into the duodenum
What is the anatomical position of the abdominal oesophagus?
C6-T11
Where does the abdominal oesophagus terminate?
At the cardiac orifice of the stomach at T11
Which structures are anterior to the abdominal oesophagus?
- Left vagus nerve
- Posterior surface of the heart
Which structures are posterior to the abdominal oesophagus?
- Right vagus nerve
- Left crus of diaphragm
What are the layers of the abdominal oesophagus from outer to inner?
- Serosa
- Muscle (inferior 1/3 is smooth muscle)
- Submucosa
- Mucosa (NKSSE)
What are the arterial supplies to the abdominal oesophagus?
- Left gastric artery
- Left inferior phrenic artery
What is the venous drainage of the abdominal oesophagus?
- Left gastric vein to portal circulation
- Azygos vein to systemic circulation
- Porto-systemic anastomosis
Where do the lymphatics of the abdominal oesophagus drain?
Left gastric nodes to celiac lymph nodes
What nerves supply the abdominal oesophagus?
- Anterior & posterior gastric from parasympathetic vagal trunks
- Sympathetic branches from the thoracic sympathetic trunk
What are the two openings of the stomach?
- Cardiac opening
- Pyloric opening
What is the lesser curvature of the stomach?
Medial surface from cardiac orifice to pylorus
What is the greater curvature of the stomach?
Lateral border from cardiac orifice to pyloric antrum
What are the divisions of the stomach?
- Cardia
- Fundus
- Body
- Pylorus (divided into pyloric antrum, pyloric canal, pyloric sphincter)
What is the function of the inferior oesophageal sphincter?
Allows food to pass through the cardiac orifice
What is the anatomical sphincter that controls the exit of chyme?
Pyloric sphincter
What are the blood supplies to the stomach’s lesser curvature?
- Right gastric artery
- Left gastric artery
What arteries supply the greater curvature of the stomach?
- Short gastric arteries
- Right gastro-omental artery
- Left gastro-omental artery
What is the sympathetic nerve supply for the stomach?
T6-T9 spinal cord segments via Greater splanchnic nerve to celiac plexus
What is the anatomical relation of the first part of the duodenum (D1)?
Superior to L1, ascends from pylorus, intraperitoneal for first 3cm
What structures are anterior to D1?
- Quadrate lobe of the liver
- Gallbladder
What are the characteristics of the jejunum compared to the ileum?
- Jejunum: red, wider, thicker, larger plicae circulares, fewer lymphoid nodules
- Ileum: pink, thinner, smaller plicae circulares, Peyer patches present
What is the blood supply to the cecum?
- Anterior & posterior cecal arteries from ileocolic artery
- Appendicular artery from ileocolic
What is the base location of the appendix?
1/3 way up the line joining ASIS & umbilicus (McBurney’s point)
What is the main blood supply for the ascending colon?
Ileocolic and right colic branches of SMA
What nerve supplies the sigmoid colon?
Sympathetic and parasympathetic nerves from inferior hypogastric plexuses
What is the peritoneal covering of the rectum?
Covers anterior and lateral surfaces of the first 1/3, only anterior surface of middle rectum, none on lower 1/3
What are the two main types of nerves supplying the rectum?
- Sympathetic
- Parasympathetic
What are the anatomical relations of the rectum posteriorly?
The rectum is in contact with the sacrum and coccyx; piriformis, coccygeus, and levator ani muscles; sacral plexus; and sympathetic trunks.
What is the continuation of the inferior mesenteric artery that supplies the rectum?
Superior rectal artery
What part of the rectum is dilated to form the rectal ampulla?
Lower part of the rectum
Fill in the blank: The _______ covers the anterior and lateral surfaces of the first one-third of the rectum.
Peritoneum
What arteries supply the muscular coat of the rectum?
Middle rectal artery
True or False: The lower third of the rectum is covered by peritoneum.
False
What is the venous drainage of the superior rectal vein?
Tributary of portal circulation; drains into IMV
What is the nerve supply of the rectum?
Sympathetic & parasympathetic nerves from inferior hypogastric plexuses
What supplies the mucous membrane of the rectum?
Superior rectal artery
What anatomical structure does the lower third of the rectum relate to in males?
Posterior surface of the bladder, termination of the vas deferens, seminal vesicles, and prostate
Fill in the blank: The middle rectal veins drain into the _______.
Internal iliac
What creates an anorectal portal-systemic anastomosis?
Middle rectal veins and inferior rectal veins
What is the lymph drainage of the upper rectum?
Pararectal nodes to inferior mesenteric nodes
What is the relationship of the upper two thirds of the rectum in females?
Related to the sigmoid colon and coils of ileum in the rectouterine pouch
What is the main function of the sympathetic and parasympathetic nerves supplying the rectum?
Sensitive only to stretch
What are the three teniae coli of the sigmoid colon responsible for?
Allow longitudinal fibers to form a broad band on anterior and posterior surfaces of rectum
What does the inferior rectal artery anastomose with at the anorectal junction?
Middle rectal artery
What anatomical structure does the lower third of the rectum relate to in females?
Posterior surface of the vagina
Where is the liver located?
R upper quadrant, under right costal margin & hemidiaphragm, extends to left hemidiaphragm
What are the two surfaces of the liver?
- Diaphragmatic surface
- Visceral surface
Describe the diaphragmatic surface of the liver.
Anterosuperior, smooth, convex, posterior aspect NOT covered by visceral peritoneum
What structures does the visceral surface of the liver contact?
- Abdominal part of esophagus
- Fundus of stomach
- 1st part of duodenum
- Right colic flexure & transverse colon
- Right kidney & adrenal gland
- Lesser omentum
- Gallbladder
- IVC
What is the falciform ligament?
Attaches anterior surface of liver to anterior abdominal wall (umbilicus), free edge contains ligamentum teres
What does the coronary ligament do?
Connects superior liver to inferior diaphragm, demarcates bare area of liver
What forms the triangular ligament of the liver?
Union of anterior & posterior layers of coronary ligament at apex, attached to left lobe
What is the lesser omentum?
Attaches liver to lesser curvature of stomach & 1st part of duodenum, consists of hepatoduodenal and hepatogastric ligaments
What are the recesses of the liver?
- Subphrenic
- Subhepatic
- Morison’s pouch
What is Glisson’s capsule?
Fibrous layer covering the liver
What are the two lobes of the liver?
- Smaller left lobe
- Larger right lobe
What are the accessory lobes of the liver?
- Caudate lobe
- Quadrate lobe
Where is the porta hepatis located?
Posteroinferior surface between caudate & quadrate lobes
What is the portal triad in the liver?
- Arteriole
- Venule
- Bile duct
- Lymphatic vessels
- Vagus nerve
What is the function of the hepatic artery?
Supplies non-parenchymal structures with arterial blood, divides into left & right terminal branches
What is the function of the hepatic portal vein?
Supplies liver with partially deoxygenated blood, carries nutrients from small intestines
Where does venous drainage from the liver go?
Central veins → hepatic veins → IVC
What is the hepatic plexus?
Nerve supply to the liver, enters porta hepatis, sympathetic from coeliac plexus, parasympathetic from Vagus nerve
How does lymphatic drainage of the liver occur?
- Anterior surface: Hepatic lymph nodes → Coeliac lymph nodes → cisterna chyli
- Posterior surface: Phrenic nodes & posterior mediastinal nodes → Right lymphatic & thoracic ducts
What anatomical relations surround the gallbladder?
- Anterior & superior: Inferior border of liver, anterior abdominal wall
- Posterior: Transverse colon, 1st & 2nd duodenum
- Inferior: Biliary tree, rest of duodenum
What are the main parts of the gallbladder?
- Fundus
- Body
- Infundibulum
- Neck
What is Hartmann’s pouch?
Mucosal fold in the neck of the gallbladder, common location for gallstones
Describe the biliary tree.
Hepatocytes → canaliculi & intralobular ducts & collecting ducts → hepatic ducts → common hepatic duct
What is the function of the common bile duct?
Descends and joins with the main pancreatic duct at the hepatopancreatic ampulla, regulated by the sphincter of Oddi
What is the anatomical position of the pancreas?
Level of transpyloric plane (L1), tail is retroperitoneal
What are the anatomical relations of the pancreas?
- Stomach: Anterior
- Duodenum: Outlines head
- Transverse mesocolon: Attaches anterior surface
- Common bile duct: Descends behind head
- Spleen: Posteriorly & laterally
What are the parts of the pancreas?
- Uncinate process
- Head
- Neck
- Body
- Tail
What forms the hepatic portal vein?
Union of superior mesenteric vein (nutrients) and splenic vein (products of RBC breakdown)
What are examples of porto-systemic anastomoses?
- Inferior esophagus
- Anal canal
- Peri-umbilical region
- Posterior aspect of liver
What is the uncinate process of the pancreas?
Lower part of the head of the pancreas
How is the head of the pancreas connected to the duodenum?
By connective tissue
Where is the neck of the pancreas located?
Behind the head and body of the pancreas
What is the anatomical position of the tail of the pancreas?
Close proximity to the hilum of the spleen; contained within the splenorenal ligament with the splenic vessels
What is the only intraperitoneal part of the pancreas?
Tail of the pancreas
What are the two main components of the duct system of the pancreas?
- Endocrine pancreas (islets of Langerhans)
- Exocrine pancreas (lobulated serous gland)
What hormones are produced by the endocrine pancreas?
- Insulin
- Glucagon
What is the role of acini in the pancreas?
Clusters of cells that produce digestive enzyme precursors
What is the main pancreatic duct’s function?
Drains digestive enzymes into the duodenum
What does the accessory pancreatic duct drain into?
Minor duodenal papilla
What structure does the pancreatic duct join with before entering the duodenum?
Common bile duct
What is the vasculature supplying the pancreas?
- Pancreatic branches of splenic artery
- Superior and inferior pancreaticoduodenal arteries
What veins drain the pancreas?
- Pancreatic veins
- Superior mesenteric branches of hepatic portal vein
What lymph nodes are involved in the lymphatic drainage of the pancreas?
Pancreaticosplenal and pyloric nodes
Which nerve fibers supply the pancreas?
Sympathetic and parasympathetic vagal nerve fibers
What mnemonic is used to remember the causes of pancreatitis?
GET SMASHES
What does each letter in the mnemonic GET SMASHES stand for?
- G ⇒ Gallstones
- E ⇒ Ethanol
- T ⇒ Trauma
- S ⇒ Steroids
- M ⇒ Mumps
- A ⇒ Autoimmune
- S ⇒ Scorpion Stings
- H ⇒ Hypertriglyceridemia, hypercalcaemia, and hyperparathyroidism
- E ⇒ ERCP
- D ⇒ Drugs (sodium valproate, azathioprine)
What are common presentations of pancreatitis?
- Epigastric pain (radiating to back)
- Nausea
- Vomiting
- Diarrhoea
In which quadrant of the abdomen is the spleen located?
Upper left quadrant
What connects the spleen to the stomach?
Gastrosplenic ligament
What is the anatomical shape of the spleen?
Oval shaped
What is the function of the weak capsule of the spleen?
Allows the spleen to expand in size
What arteries supply the spleen?
- Splenic artery (arising from coeliac trunk)
- Five branches that do not anastomose
What is the venous drainage of the spleen?
Splenic vein, which combines with the superior mesenteric vein to form the hepatic portal vein
What innervates the spleen?
Coeliac plexus
What are the layers of the abdominal oesophagus from outer to inner?
- Serosa
- Muscle (inferior 1/3 smooth muscle)
- Submucosa
- Mucosa (NKSSE)
What is the arterial supply of the abdominal oesophagus?
- Left gastric artery
- Left inferior phrenic artery
What are the two main openings of the stomach?
- Cardiac opening
- Pyloric opening
What are the divisions of the stomach?
- Cardia
- Fundus
- Body
- Pylorus
What anatomical structure demarcates the transpyloric plane?
Pyloric sphincter
What does the pyloric sphincter control?
Exit of chyme from the stomach
What is the function of the suspensory ligament of the duodenum?
Widening of the duodenojejunal flexure to aid movement of contents
What anatomical relations are associated with the first part of the duodenum (D1)?
- Anteriorly: Quadrate lobe of the liver and gallbladder
- Posteriorly: Lesser sac, gastroduodenal artery, bile duct, portal vein, inferior vena cava
- Superiorly: Entrance to lesser sac
- Inferiorly: Head of pancreas
What anatomical relations are associated with the second part of the duodenum (D2)?
- Anteriorly: Fundus of gallbladder, right lobe of liver, transverse colon, coils of small intestine
- Posteriorly: Hilum of right kidney and right ureter
- Medially: Head of pancreas, bile duct, and main pancreatic duct
What anatomical relations are associated with the third part of the duodenum (D3)?
- Anteriorly: Root of the mesentery and coils of jejunum
- Posteriorly: Right ureter, right psoas muscle, inferior vena cava, and aorta
What anatomical relations are associated with the fourth part of the duodenum (D4)?
- Anteriorly: Beginning of the root of mesentery and coils of jejunum
- Posteriorly: Left margin of the aorta and medial border of left psoas muscle
What is the role of contraction in the duodenum?
Widening of flexure to aid movement of contents
What structures are located anteriorly to the duodenum?
The beginning of the root of the mesentery and coils of jejunum
Which structures are found posteriorly to the duodenum?
The left margin of the aorta and the medial border of the left psoas muscle
What is the arterial supply to the upper half of the duodenum?
Superior pancreaticoduodenal artery (celiac trunk)
What artery supplies the lower half of the duodenum?
Inferior pancreaticoduodenal artery (SMA)
What is the venous drainage of the superior pancreaticoduodenal vein?
Portal vein
What nodes are involved in lymph drainage of the upper duodenum?
Pancreaticoduodenal nodes to pyloric nodes to celiac nodes
What nerves supply the duodenum?
Sympathetic and parasympathetic nerves derived from celiac and superior mesenteric plexuses
Where is the cecum located?
Between ileum and ascending colon
What is the function of the ileocecal valve?
Prevents reflux from cecum into ileum
What anatomical structures are found anteriorly to the cecum?
Coils of the small intestine, part of the greater omentum, anterior abdominal wall
What creates cecum recesses?
Presence of peritoneal folds
What is the blood supply to the cecum?
Anterior and posterior cecal arteries from the Ileocolic artery
What is the base of the appendix located in relation to the ASIS and umbilicus?
1/3 way up the line joining ASIS and umbilicus (McBurney’s point)
What is the most common position of the appendix?
Retrocecal
What is the nerve supply to the appendix?
Sympathetic and parasympathetic (vagus) nerves from superior mesenteric plexus
What is the primary blood supply to the ascending colon?
Ileocolic and right colic branches of SMA
What is the function of the transverse mesocolon?
Suspends transverse colon via anterior border of pancreas
What is the blood supply to the transverse colon?
Middle colic artery from SMA for proximal 2/3; left & right colic arteries for distal 1/3
What is the relationship of the descending colon posteriorly?
Lateral border of the left kidney, quadratus lumborum, iliac crest, left psoas
What arteries supply the sigmoid colon?
Sigmoid arteries from IMA
What is the anatomical position of the rectum?
Located in the pelvic cavity, posterior to the sigmoid colon
What is the relationship of the sigmoid colon to the ileum?
Related to the lower coils of the terminal part of the ileum
What is the blood supply of the sigmoid colon?
IMA ⇒ sigmoid arteries ⇒ ascending & descending branches
What veins drain the sigmoid colon?
Sigmoid veins ⇒ IMV
What nerves supply the sigmoid colon?
Sympathetic & parasympathetic nerves from inferior hypogastric plexuses
Where does lymph drainage from the sigmoid colon go?
Paracolic & Intermediate colic nodes ⇒ Inferior mesenteric nodes
What anatomical structure does the rectum continue with?
Anal canal
What is the anatomical position of the rectum?
S3 ⇒ tip of coccyx & piercing the pelvic diaphragm
What dilated structure forms the lower part of the rectum?
Rectal ampulla
What surfaces does the peritoneum cover in the rectum?
Covers ant. & lat. surfaces of 1st 1/3 of rectum; only ant. surface of middle rectum; none on lower 1/3
What are the layers of the muscular coat of the rectum?
Outer longitudinal & inner circular layers of smooth muscle
What allows longitudinal fibres to form a broad band on the rectum?
3 teniae coli of sigmoid colon
What is the posterior anatomical relation of the rectum?
In contact with sacrum, coccyx, piriformis, coccygeus, levator ani muscles, sacral plexus, and sympathetic trunks
What anatomical structures are anterior to the upper two thirds of the rectum in males?
Sigmoid colon and coils of ileum in the rectovesical pouch
What anatomical structures are anterior to the lower third of the rectum in males?
Posterior surface of the bladder, termination of the vas deferens, seminal vesicles, and prostate
What anatomical structures are anterior to the upper two thirds of the rectum in females?
Sigmoid colon and coils of ileum in the rectouterine pouch (pouch of Douglas)
What anatomical structures are anterior to the lower third of the rectum in females?
Posterior surface of the vagina
What is the arterial supply of the rectum?
Superior rectal artery (continuation of IMA), Middle rectal artery (branch of internal iliac artery), Inferior rectal artery (internal pudendal artery)
What does the superior rectal artery supply?
Mucous membrane
What is the venous drainage of the rectum?
Superior rectal vein drains into IMV; Middle rectal veins drain into internal iliac; Inferior rectal veins drain into internal pudendal veins
What type of anastomosis do the middle and inferior rectal veins create?
Anorectal portal-systemic anastomosis
What is the nerve supply to the rectum?
Sympathetic & parasympathetic nerves from inferior hypogastric plexuses; sensitive only to stretch
Where does lymph from the upper rectum drain?
Pararectal nodes ⇒ inferior mesenteric nodes
Where does lymph from the lower rectum drain?
Follows middle rectal artery to internal iliac nodes
