The Biliary System
Mr E. Leung
Content
• Surgical Anatomy
• Physiology
• Investigations for biliary tree
• Common Pathology
SURGICAL ANATOMY
Surgical Anatomy - Gallbladder
• Pear shaped
• 7 – 13 cm in length,
Volume ~ 50ml
• Cystic duct 1 – 3cm
– Spiral valves of Heister
• Fundus, body, neck
and Hartmann’s pouch
Surgical Anatomy - Gallbladder
• Lies between quadrate
lobe and right lobes
• Covered in peritoneum
except the GB fossa
Surgical Anatomy - Gallbladder
• 1st + 2nd part of
duodenum lies behind
• T-colon lies inferiorly
• Common Bile Duct (CBD)
– 7cm long
– 7mm wide
– pressure of 7mmHg
Surgical Anatomy – Calots Triangle
Surgical Anatomy – Common Bile Duct
• CBD = CHD + cystic duct
– Supraduodenal part –
• free edge of lesser sac
• 2.5cm long
– Retroduodenal part
– Infraduodenal part
– Intraduodenal part
Surgical Anatomy – Major and minor papilla
• CBD enters duodenum
posteromedially
• Joins pancreatic duct =
Ampulla of Vater
– (10cm from pylorus)
• Accessory pancreatic
duct joins duodenum
via minor papilla
Endoscopic view of Ampulla of Vater,
also known as Major duodenal papilla
Surgical Anatomy – Sphincter of Oddi
• Circular muscle of
duodenum wraps
around the confluence
of the pancreatic duct
and CBD
• Forms a sphincter and
prevents reflux of
duodenal contents
Surgical Anatomy – nerve supply
• T7-9 sympathetic and parasympathetic vagus
• Afferent fibres (including pain) => coeliac plexus
=> greater splanchnic nerves => dorsal ganglia
• Preganglionic efferent fibres => coeliac plexus
=> postganglionic fibres run along the hepatic artery
• Vagus stimulation = GB to contract, Oddi to relax
PHYSIOLOGY
Physiology – Bile salts
• Bile = 97% water, 2% bile salts, 1% pigments
• Bile acids are synthesised in the liver from cholesterol
• Primary bile acids = chenodeoxycholic + cholic acid
– Conjugated with Taurine + Glycine = water soluble bile salts
• Secondary bile salts = gut bacterial metabolism
(deoxycholic and lithocholic acid)
Physiology – function of gallbladder + bile
• Concentrates and
stores bile (upto 10x)
• Mucin secretion
• Bile + small globlets of
fat = micelles
• Allows digestion by
lipases
Physiology – The enterohepatic circulation
• Secretin and CCK, secreted
by duodenum
• low pH or high fat content
• CCK => GB to contract and
Oddi to relax
• Secretin => bile production
and pancreatic juice release
CLINICAL INVESTIGATIONS
Investigations
• Largely radiological
• Blood tests:
– inflammatory markers, GGT, LFTs, Clotting, Amylase
• Radiology:
– AXR, USS, cholangiography (oral, iv or intraductal)
– CT, MRCP, radionuclide scans (HIDA or PIPIDA)
Radiological investigations
• Plain AXR
• USS
Radiological investigations
• Cholangiography
• CT – better at assessing
the pancreas
• MRCP – best resolution in
assessing the biliary tree
• Tc-labelled scan –
functional study
PATHOLOGY
Congenital abnormalities
• Atresia – type I, II and III or Gallbladder
– 1 in 30,000
• Double or intra-hepatic gallbladder
• Phrygian cap
• Choledochal cysts
Acquired pathology – Gallstone disease
• Very common – The 4 “F”s
– F:M = 3:1
West > East
1. Pure cholesterol stone – 5%
2. Mixed stone (70%) – Lecithin, cholesterol and salts
3. Pure pigment stones – 25%
• 90% of time is radiolucent
Causes of Gallstone formation
• Changes in bile composition, multifactorial
– Supersaturation
– Precipitation
1. Metabolic – e.g. diet, cirrhosis
2. Infective – e.g. reflux of bile
3. Biliary stagnation – e.g. pregnancy
Complications of gallstones
Complications of gallstones
• Biliary colic
– Analgesia then cholecystectomy
• Cholecystitis
• Mucoceole
• Perforation
 Cholangitis

Abx and ERCP, then
cholecystectomy
– Abx then cholecystectomy
• GS ileus
– Surgery
 Pancreatitis
Other benign gallbladder conditions
• Strawberry GB – lipid/cholesterol infiltration to mucosa
• Adenomyomatosis - Mucosal diverticula
• Acalculus cholecystitis – 5%
– Precipitated by illness, surgery or trauma
• Benign polyp
Symptoms of gallstone disease
Most gallstones are asymptomatic
Symptoms of gallstone disease
• Biliary colic
– Intermittent colicky RUQ pain
– Post-prandial vomiting
– Right shoulder pain
• Cholecystitis
– Constant sharp RUQ pain
– Fever and vomiting (not post-prandial)
Symptoms of gallstone disease
• Cholangitis
– Jaundiced (urine, faeces, itch)
– Rigors
– Colicky RUQ pain
• Pancreatitis
– Continuous sharp pain alleviated by leaning forward
– Other symptoms for complications of pancreatitis…
Differential diagnoses
• PUD / Gastritis / GORD
• Pancreatitis
• Liver pathology
• Cardiac
ANY QUESTIONS