The Biliary System
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Transcript of The Biliary System
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
– Abx then cholecystectomy
• GS ileus– Surgery
Cholangitis Abx and ERCP, then
cholecystectomy
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