Pastest Surgical Anatomy Of Abdomen, Pelvis And Perineum Flashcards
What is the primary function of the biliary tree?
The biliary tree receives the bile produced in the liver and stores it in the gallbladder
Bile is secreted into the duodenum to aid in fat digestion.
Which components make up the biliary tree?
- Right hepatic duct
- Left hepatic duct
- Common hepatic duct
- Gallbladder
- Cystic duct
- Common bile duct
- Accessory hepatic ducts
Accessory hepatic ducts are found in about 15% of the population.
What is the percentage of finding accessory hepatic ducts in the population?
15%
What is the length range of the right and left hepatic ducts?
Right duct: 0.5-2.0 cm; Left duct: 1.5-3.5 cm
The right duct is shorter than the left duct.
What structures are found at the porta hepatis from anterior to posterior?
Mnemonic; P(H)2
- Right and left branches of (P)ortal vein
- (H)epatic artery proper
- Right and left (H)epatic ducts
This arrangement is crucial for understanding the anatomy of the liver.
What forms the common hepatic duct?
The union of right and left hepatic ducts near the right end of the porta hepatis
The common hepatic duct is about 3 cm long.
What is the location of formation of the common bile duct?
Near the right end of porta hepatis
What is the length of the common bile duct?
3 cm
Where does the common hepatic duct lie in relation to other structures?
- Lies in the free edge of the lesser omentum
- Hepatic artery is on its left
- Portal vein is located posteriorly
These structures form the anterior boundary of the foramen of Winslow.
What are the dimensions of the gallbladder?
- Length: 7-10 cm
- Breadth: 3 cm in the widest part
- Capacity: 30-50 ml
These dimensions can vary based on individual anatomy.
What are the parts of the gallbladder?
- Fundus
- Body
- Neck
The fundus projects below the inferior border of the liver and is completely covered with peritoneum.
What covers the fundus of the gallbladder?
Completely covered with Peritoneum
What is the location of the fundus of the gallbladder?
projects below the inferior border of the liver and is completely covered with peritoneum
What is Hartmann’s pouch?
An outpouching of the neck of the gallbladder
Gallstones may impact here and cause cystic duct obstruction.
What is the clinical significance of the Hartmann’s pouch?
Gallstones may impact here and cause cystic duct obstruction
Describe the cystic duct.
+ 2-4 cm long and
+ 2-3 cm wide,
+ begins at the neck of the gallbladder
It joins the common hepatic duct at an acute angle, near the right end of porta hepatis, to form the common bile duct.
What is the length of the cystic duct?
2-4 cm
What is the width of the cystic duct?
2-3 cm
where is the location of beginning of cystic duct?
at the neck of the gallbladder
What is the function of the valve of Heister?
The mucous membrane is folded spirally in the cystic duct
It is not a true valve.
It helps to maintain the patency (openness) of the cystic duct, preventing it from collapsing due to its tortuous course, rather than regulating bile flow as originally believed; their exact function remains somewhat debated among anatomists.
What is the length range of the common bile duct in adults?
6-8 cm long
The normal diameter is up to 6 mm and increases with age.
What is the normal diameter of the common bile duct in aduts?
6 mm and increases with age
What is the effect of the age on the normal diameter of the common bile duct?
increases with age
List the four parts of the common bile duct.
- Supraduodenal part
- Retroduodenal part
- Infraduodenal part
- Intraduodenal part
Each part has specific anatomical relations.
What is the ampulla of Vater?
A dilatation in the common bile duct that opens into the duodenum
It lies 8-10 cm distal to the pylorus.
What is the location of the ampulla of Vater?
It lies 8-10 cm distal to the pylorus
Where does the ampulla of Vater open?
opens into the duodenum
What is the length of the sphincter choledochus?
15-20 mm long
It regulates the flow of bile and pancreatic secretions into the duodenum.
What is the function of the sphincter choledochus?
It regulates the flow of bile and pancreatic secretions into the duodenum
What structures define the boundaries of the hepato-biliary triangle?
- Cystic duct
- Common hepatic duct
- Inferior surface of the liver
It contains important vascular and lymphatic structures.
What are the boundaries of Calot’s triangle?
- Cystic duct
- Common hepatic duct
- Cystic artery
Calot’s triangle is significant in surgical anatomy.
Where does the fundus of the gallbladder lie?
The fundus of the gallbladder lies
(1) opposite the junction of the costal margin and the lateral border of the right rectus abdominis muscle
(2) or just below the tip of the right ninth costal cartilage.
It is related anteriorly with the anterior abdominal wall and posteriorly with the transverse colon.
What structures is the body of the gallbladder related to?
The body of the gallbladder is related to the transverse colon and the first and second parts of the duodenum.
What are the layers of the gallbladder?
(1) inner — mucous membrane (mucosa), single layer of tall columnar cells with a brush border of microvilli, very similar to intestinal absorptive cells
(2) middle — lamina propria (fibromuscular layer), and
(3) outer — serous layer (serosa).
What covers the inferior and superior surfaces of the gallbladder?
The serous layer— covers the inferior surface and
adventitia— covers the superior surface.
What type of epithelium lines the mucous membrane of the gallbladder?
The mucous membrane is lined with simple tall columnar epithelium with microvilli.
What does the lamina propria of the gallbladder lack?
The lamina propria lacks the
(1) mucosal glands and
(2) lymphatic vessels.
What is absent in the gallbladder’s structure?
Muscularis mucosa and submucosa are absent.
What is the location of fibromuscular coat in the gallbladder?
Outside the lamina propria is the fibromuscular coat.
What are Rokitansky-Aschoff sinuses?
*Def— Deep mucosal diverticula
*Location— extend into the muscularis externa
*Clinical significance— contribute as a risk factor for stone formation and infection.
What is the arterial supply of the gallbladder?
The cystic artery is a branch of the right hepatic artery, supplying the gallbladder, cystic duct, hepatic ducts, and upper part of the common bile duct.
How does the common bile duct receive blood supply?
The common bile duct and hepatic ducts are supplied by a fine network of arteries arranged at 3 and 9 o’clock positions from multiple sources including the cystic artery and right hepatic artery.
What supplies the lower part of the common bile duct?
Branches from the posterior superior pancreaticoduodenal artery and the retroduodenal artery supply the lower part of the common bile duct.
How does venous drainage occur from the gallbladder?
Veins from the superior surface of the gallbladder enter the liver through the gallbladder fossa and join hepatic vein tributaries.
Where does the venous blood from the remaining gallbladder drain?
It drains into small cystic veins that join the right branch of the portal vein.
Where does the venous drainage from the lower bile duct join?
The venous drainage from the lower bile duct joins the portal vein.
Where does the cystic lymph node of Lund lie?
The cystic lymph node of Lund lies in the angle between the cystic duct and the common hepatic duct.
How do lymphatics from the gallbladder and cystic duct drain?
They drain into the cystic node and nodes along the free edge of the lesser omentum, nodes along the common hepatic artery, and then the celiac lymph nodes.
Where do lymphatics that descend along bile ducts drain?
They drain into the superior retro-pancreaticoduodenal node that further drains into para-aortic nodes.
Where do lymphatics from the hepatic aspect of the gallbladder drain?
They drain directly into intrahepatic lymphatics.
Where do lymphatics from the upper biliary tree drain?
They drain into hepatic nodes at the porta hepatis, which further drain into nodes along the free edge of the lesser omentum and then into celiac nodes.
What is the nerve supply to the gallbladder?
The cystic plexus of nerves receives fibers from the celiac plexus via the hepatic plexus, both right and left vagus nerves, and the right phrenic nerve.
What is the role of parasympathetic nerves in the gallbladder?
The parasympathetic nerves are motor to the gallbladder and bile ducts and inhibitory to sphincters.
What triggers gallbladder contraction?
Gallbladder contraction occurs in response to cholecystokinin.
What inhibits gallbladder contraction?
Postganglionic sympathetic nerve fibers from the coeliac and superior mesenteric ganglia inhibit gallbladder contraction.
How is gallbladder pain referred?
Visceral pain from the gallbladder is referred to the right hypochondrium, epigastrium, and below the right scapula.
What causes localized right upper quadrant pain?
Inflammation of the parietal peritoneum overlying the gallbladder produces localized right upper quadrant pain.
How is referred pain to the right shoulder transmitted?
Referred pain to the right shoulder is through the right phrenic nerve as C4 gives fibers to this nerve and supraclavicular nerves.
From what does the gallbladder develop?
The gallbladder and cystic duct develop from pars cystica of the hepatic bud that arises from the endoderm of the caudal part of the foregut.
What does pars hepatica form?
Pars hepatica forms the common bile duct, common hepatic duct, and right and left hepatic ducts.
Where does the bile duct initially drain?
Initially, the bile duct drains into the ventral aspect of the developing duodenum.
Where does the bile duct finally open?
Due to rotation of the duodenal loop, the bile duct finally opens into the dorsomedial aspect of the duodenum along with the ventral pancreatic bud.
What are the components of the aorta?
The aorta has thoracic and abdominal components.
What is the length of the ascending thoracic aorta?
5 cm
Where does the ascending thoracic aorta begin?
at the aortic valve.
What are the three bulges in the wall of the ascending aorta called?
sinuses of Valsalva :
The right and left posterior, and anterior aortic sinuses.
Which aortic sinuses give rise to the coronary arteries?
The anterior and left posterior aortic sinuses give rise to the right and left coronary arteries, respectively.
What does the right posterior aortic sinus give off?
The right posterior aortic sinus does not give off any vessels.
Where does the aortic arch start and end?
The aortic arch starts behind the right margin of the sternum and ends at the level of T4.
What arteries does the aortic arch give rise to?
It gives rise to the brachiocephalic, left common carotid, and left subclavian arteries.
Where does the descending thoracic aorta lie?
The descending thoracic aorta lies in the posterior mediastinum.
What is the extent of the descending thoracic aorta?
It extends between T4 and T12.
What branches does the descending thoracic aorta give?
It gives branches to the
(1) pericardium,
(2) lungs,
(3) bronchi,
(4) oesophagus, and
(5) intercostal and superior phrenic arteries.
Where does the abdominal aorta enter the abdomen?
The abdominal aorta enters the abdomen between the diaphragmatic crura, anterior to T12, as a continuation of the thoracic aorta.
At what level does the abdominal aorta bifurcate?
It descends on the vertebral bodies until its bifurcation at the level of the body of L4 where it bifurcates into the common iliac arteries, between which lies the small median sacral artery.
What are the common branches of the abdominal aorta?
(1) common iliac arteries
(2) small median sacral artery— between the common iliac arteries,
What structures cross anteriorly over the abdominal aorta?
(1) splenic vein,
(2) body of the pancreas,
(3) third part of the duodenum, and
(4) left renal vein.
What lies to the right of the abdominal aorta?
(1) inferior vena cava,
(2) right ureter, and,
(3) more proximally, the azygos vein.
What lies to the left of the abdominal aorta?
(1) left sympathetic trunk
(2) left ureter.
What are the three paired visceral branches of the abdominal aorta?
Middle suprarenal (adrenal), renal, and gonadal arteries.
What are the three unpaired visceral branches of the abdominal aorta?
Coeliac axis, superior mesenteric artery, and inferior mesenteric artery.
What are the parietal branches of the abdominal aorta?
One pair - inferior phrenic; four pairs - lumbar; median sacral artery (variable).
What are the two types of arteries?
(1) Elastic conducting arteries (e.g., aorta)
(2) muscular distributing arteries (e.g., femoral artery)
What is the function of elastic conducting arteries?
They expand to take the forward blood flow of systole and recoil during diastole (this provides constant blood flow)
What is the histological content of the elastic conducting arteries?
(1) High amount of elastin and collagen in the media
(2) fewer smooth muscle cells(which predominate in muscular arteries)
What happens to the muscular distributing arteries?
Taper as the media thins down to a few layers of vascular smooth muscle cells and become arterioles
What is the histological composition of arteries?
Arteries consist of three layers: tunica intima, tunica media, and tunica adventitia.
What is the tunica intima?
The innermost layer composed of a single layer of endothelial cells which are oriented in the direction of flow and have a role in both coagulation and vasomotor tone
What is the tunica media?
The middle layer composed of elastin, collagen fibres, and vascular smooth muscle cells.
What is the function of the tunica media?
(1) control vasomotor tone
(2) Synthesise structural proteins of the vessel wall
What is the tunica adventitia?
The outermost layer of connective tissue.
How does the histology of the aortic wall change as it descends?
The thoracic aorta has > 30% elastin, compared with < 20% in the abdominal section.
