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8 Biliary Diseases

ANATOMY OF THE EXTRAHEPATIC BILIARY SYSTEM• Anatomy of the biliary system is highly

variable,andthisincludesducts,arteries,veins,andlymphatics.

Common Hepatic Duct• Intrahepatic biliary duct systems converge on

rightandlefthepaticducts.• Right and left hepatic ducts typically form the

commonhepaticduct.• Leftductisusuallylonger.• Junctionoftheductsmaybeintrahepatic(e.g.,

inhepatomegaly).• Accessoryhepaticductscanoccur.• There may be no common hepatic duct

if the cystic duct empties into right and lefthepatic duct junction (bile duct branchvariant).

Gallbladder• NormallyliesbetweenhepaticsegmentsIVand

V, in a ventral fossa between the anatomicalrightandleftlobes

• Ventralsurfacetypicallyliesincontactwiththedescendingpartoftheduodenum.

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Right and lefthepatic ducts

Commonhepatic duct

(Common)bile duct

Cysticartery

Cystic duct

Gallbladder

Right and lefthepaticarteries

Proper hepaticartery

Commonhepaticartery

Hepatic ductsCystic duct

Right LeftSpiralfold

Smoothpart

Commonhepaticduct

NeckInfundibulum(Hartmann’spouch)

Body

Fundus

Hepatopancreaticampulla (of Vater)

Descending(2nd) part ofduodenum Pancreatic

duct

(Common)bile duct

Viscera: Gallbladder and Extrahepatic Ducts

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• Peritoneum surrounds fundus and attachesbody and neck to the ventral surface of theliver.

• Hepatic surface of the gallbladder has fibroustissueconnectionstolivercapsule.

• Mucosan Columnarepithelium,nosubmucosan ActivelyabsorbsNa+andwater,concentrating

bile• Smoothmuscleofthefibromuscularlayerispri-

marilyorientedlongitudinally.• Parasympatheticpreganglionicinnervationfrom

left(anterior)vagusfiberscontractsgallbladderandrelaxesbileductsphincter.

• Postganglionic sympathetic fibers from theceliacganglionaredrivenbypreganglionicfibersfromT7-T10spinalsegmentstravelingingreatersplanchnicnerves.

• Visceral afferent fibers (e.g., pain) travel backtoward thoracic spinal ganglia, through theceliac plexus and greater splanchnic nerve,alongsideincomingsympathetics.

Cystic Duct• Proximalportionisconvoluted;spiralfoldkeeps

theductopen.• Distalportionissmooth.• Typical cystic duct joins the common hepatic

ductwellbelow the rightand lefthepaticductjunction.

• Triangle of Calot: classic configuration (shownabove)withcysticductright,commonbileductleft,liverabove,andrighthepaticarterypassingthrough

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Low unionwith commonhepatic duct

Adherent tocommonhepatic duct

Highunion withcommonhepaticduct

Cystic ductabsent orvery short

Anterior spiraljoining commonhepatic duct onleft side

Posterior spiraljoining commonhepatic duct onleft side

Joiningcommonhepatic duct

Joiningcystic duct

Variations in cystic duct

Accessory (aberrant) hepatic ducts

Joining(common)bile duct

Joininggallbladder Two accessory

hepatic ducts

Variations in Cystic and Hepatic Ducts

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Cystohepatic Junction• Classicnormal

n High, sub-hepatic origin of the commonhepaticduct

n Joinedinferiorly,atananglefromtheright,bythecysticduct(<3cm)

n Produces the (common) bile duct some dis-tanceabovethedescendingduodenum

• Variationsn Shortorabsentcysticductn Cysticductparalleltohepaticductn Insertionintorighthepaticductn Lowinsertionofcysticduct,crossinganterior

tocommonhepaticduct,insertingbehindtheduodenum

n Low medial insertion of (anterior crossing)cysticductintobileduct

n Lowanterior insertionof(posteriorcrossing)cysticductintobileduct

• Anatomical types of cystohepatic junction:angular,parallel,spiral

Ducts of Luschka• Small biliary ducts that connect directly from

livertothegallbladder• Potential source of leakage following

cholecystectomy

(Common) Bile Duct• Formedbytheunionofhepaticandcysticducts• Portions:supraduodenal,retroduodenal,pancre-

atic,intraduodenal• Bileductsphincter:smoothmusclesurrounding

thedistalendof theduct,partof thecomplexsphincterofOddi

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Dimensions• 4-8mmdiameternormalundilated• Diametertendstoincreasewithadvancedage.• Heuristic:normalductdiameterinmm=age/10

Hepatopancreatic Ampulla (Vater)• Formedbytheunionofthe(common)bileduct

andthemainpancreaticduct• Ampulla empties posteromedially through the

majorduodenalpapilla(ofVater)intotheretro-peritoneal, descending (second) part of theduodenum.

• Hepatopancreatic sphincter (of Oddi): formedfromacomplexof smoothmuscle surroundingtheterminalpartoftheampullaanditscontrib-utingduct

Bile Secretion• Increased by cholecystokinin (CCK), secretin,

andvagalactivity• Decreased by vasoactive intestinal peptide

(VIP),somatostatin,sympatheticactivity• CCKcausestonicgallbladdercontraction.• Bilemediatesabsorptionoffat-solublevitamins

andexcretionofbilirubinandcholesterol.

VESSELS AND LYMPHATICSArteries• Gallbladderissuppliedbycysticartery,typically

a branch of the right hepatic artery (from thehepatic artery proper, off common hepatic,celiacaxis).

• Source and course of the cystic artery vary widely: this must be carefully determined incholecystectomy.


Right hepaticartery

Cystic artery

Cystohepatictriangle(of Calot)

Cystic duct

Commonhepaticduct

(Common)bile duct

Supraduodenalartery

Gastroduodenalartery

Left hepaticartery Common hepatic

artery

Celiac trunk

Biliary System Arteries

• Variants includeorigins fromcommonhepatic,left hepatic, superior mesenteric arteries,passing anterior or posterior to hepatic or bileducts.

• Bile ducts: supplied by branches of posteriorsuperior pancreaticoduodenal, retroduodenal,right,andlefthepaticarteries(celiacaxis)


Veins• Cystic veins are variable; veins from the body

typicallypassdirectlyintothelivertodrainintohepaticsinusoids.

• Otherveinsfromtheneckandcysticducttypi-callydraindirectlyintotherightportalvenoussystem, and other veins drain the biliary ductsystem.

Lymphatics• Cysticlymphnodesclusteraroundtheneck.• Cysticlymphaticsalsodrainintohepaticnodes

clusteredaroundtheupperbileduct.• Deeper drainage into celiac nodes around the

arterialtrunk

CLINICAL CORRELATESNormal Bile Production• 500to1000mL/day• Secretin production and meals rich in fats

increasebileproduction.• Bile constituents: electrolytes, bile salts, pro-

teins,cholesterol,fats,andbilepigments• Major salts: cholic, deoxycholic, and chenode-

oxycholic acids; anionic and conjugated withtaurineorglycine

• Contains unesterified cholesterol, lecithin, andfattyacids

• pHof5.6-8.6isnormalrange.n Morealkalineathighersecretionratesn Moreacidicwithproteininmeals

• Cholesterolsolubilityandlackofstoneprecipi-tationdependonabalanceamongcholesterol,bilesalts,andlecithin(inmicelles).


Left gastricnodes

Hepaticnodes

Celiac nodes

Pyloricnodes

Cystic node(of Calot)

Pancreatico-duodenalnodes

Hepatic nodesaround bileducts andproper hepaticartery

Lymph Vessels and Nodes of Pancreas


• Gallbladderalsosecretesmucus,whichprotectstissuesfromthelyticactionofbile.

Control of Bile Secretion• Bile produced by the liver is shunted to the

gallbladder,withthesphincterofOdditonicallyclosed(betweenmeals).

• Cholecystokininissecretedbyintestinalmucosainresponsetoingestionoffood.

• Gallbladder contracts and pushes bile into theductalsystem.

• Sphincter of Oddi relaxes, and bile is releasedintoduodenum.

Cholelithiasis• Incidence: about 10% of the population, with

mostasymptomatic• Diabetics not at increased risk, though inflam-

matory responses can complicate late-detectedcases,withhigherincidenceofopensurgery

• Onlyabout10%ofbilestonesareradiopaque.• Nonpigmentedstones

n MostcommontypeinU.S.(~75%)n Increasedinsolubilizationofcholesteroln Factors can include cholestasis, increased

H2O reabsorption, Ca2+ nucleation by mucinglycoprotein, and decrease in bile acids andlecithin.

• Pigmentedstonesn Occurrence ~25% in U.S., most common

worldwiden Precipitationofcalciumbilirubinateandinsol-

ublesalts,withsolubilizationofunconjugatedbilirubin


Mechanisms of biliary pain

Visceral pain, mediated bysplanchnic nerve, results fromincreased intraluminal pressure and distention caused by suddencalculous obstruction of cystic orcommon duct.

Sites of pain in bilary colic

Sites of pain and hyperesthesiain acute cholecystitis

Patient lies motionlessbecause jarring or respiration increasespain. Nausea is common.

Parietal epigastric or rightupper quadrant pain results fromischemia and inflammation of gall-bladder wall caused by persistentcalculous obstruction of cystic duct.Prostaglandins are released.

Sudden obstruction(biliary colic)

Persistent obstruction(acute cholecystitis)

Calculus in Hartmann’spouch

Edema, ischemia,and transmuralinflammation

Transduodenalview ofbulging of ampulla

Ampullarystone

Calculus in common duct

Cholelithiasis


n Black stones may be caused by cirrhosis,hemolyticdisorders,ilealresection,orchronictotalparenteralnutrition(TPN).

n Usuallyfoundonlyinthegallbladder

Diagnostic Procedures• Liverandbiliaryfunctiontests

n Serumalkalinephosphatase:verysensitivetoobstruction; sensitivity increased by isoen-zymedatabloodlevels

n Serumglutamic-oxaloacetictransferase(AST/SGOT)bloodlevels

n Serum glutamate-pyruvate transaminase(ALT/SGPT)bloodlevels

n Lacticaciddehydrogenase(LDH)bloodlevelsn Bloodbilirubinlevels

• Ultrasoundn Often the first test ordered for suspected

biliarytractdiseasen Safe,inexpensiven 95% sensitivity for stones, identifies gallblad-

dermorphologyandmechanicalvs.metabolicsourcesofjaundice

• Endoscopic retrograde cholangiopancreatogra-phy(ERCP)n Catheter from a side-viewing endoscope is

insertedintotheampullaofVater.n Contrastagentisinjected.n Radiographsaretaken.n Devicecanperformsphincterotomyifneeded.n Standing questions: What are indications for

performing an ERCP before a lap chole?Blockedbileduct?May identifyvariantsandreduceinjuries?


Cholecystitis• Gallbladderwalldistentionandinflammation• Mostcommoncauseisobstructionofthecystic

ductbyastone.• Classic right upper quadrant pain referred to

rightscapulaandshoulder• Pain mediated by segmental visceral afferent

fibers traveling with the splanchnic nerves (tothoracicspinalsegments)

• Nausea,vomiting,lossofappetite,pain• Symptomsoftenoccurafterfattymeal,withper-

sistentpain.• Murphy’s sign: patient resists deep inspiration

owingtopain,withdeeppalpationofrightupperquadrant

• Ultrasound~95%sensitivityforstones• Risk factors for stones: female, obesity, age

>40y, pregnancy, rapid weight loss, vagotomy,TPN,ilealresection

Cholecystectomy• Laparoscopic cholecystectomy (lap chole)

has been the treatment of choice for manyyears, preferred to formerly traditional opencholecystectomy.

• Complicated laparoscopic case may be con-vertedtoanopencholecystectomy.

• Opencholecystectomyusesconventionalsurgi-cal instrumentswitharightupperquadrantormidlineabdominalincision.

• Lapcholeessentialsn Generalanesthesia,sub-umbilicalincisionfor

CO2(insufflation)trocar


n 3trocarsplaced(forlaparoscopeandspecial-izedtools)inrightsubcostalregion

n Retraction of gallbladder, incision of triangleofCalot

n Dissection and ligation of cystic duct andartery

n Dissectionandremovalofgallbladder• Mostcommonbileductinjuriesassociatedwith

laparoscopiccholecystectomyn (Common)bileductmistakenforcysticduct

andtransectedn Variable extent of extrahepatic biliary tree

excisedwithgallbladdern Righthepaticarteryinjuredwithdissection

Gallstone Pancreatitis• Estimated40%ofacutepancreatitiscasesresult

from transient obstruction of pancreatic ductflowbystonesblockingbileductorampullaofVater.

• Mechanismofsuchpancreatitisnotknown• Symptoms: epigastric and radiating back pain,

nausea, vomiting, elevated serum lipase andamylaselevels

• Treatmentcancomplicatethetimingofarelatedcholecystectomy.

• ERCPmaybeneededifanimpactedampullaissuspected.

Carcinoma of the Biliary Tract• Canoccuratanypointalongtheintra-orextra-

hepaticbiliarytreeandgallbladder• Gallbladder carcinoma is the most common

biliary cancer and the fifth most common GIcancer.