Biliary Flashcards
Choledochal Cyst
Rare congenital cystic dilatations of the biliary tree
Risk factors
- Hep fibrosis, APBJ, Biliary atresia, PKD (AR and AD), Colonic atresia, Imperforate anus
- Others - Double CBD, multiseptate GB, Panc AVM, heterotopic panc FAP
Path - disorders of embryological proliferation of biliary epithelium, likely related to ABPJ - reflux of panc secretions damaging biliary tree
- ABPJ - junction outside duodenal wall with channel over 8mm
- Risk of intraductal activation of enzymes - assoc w high amylase in bile
Histo - from normal cuboidal to ca - fibrotic / chronic inflamed - can have BiliN
Clin - children often, if syx - abdo P, jaundice,
- Complications - cholangitis, panc, obst, malig, obst, GOO, cyst bleeding, rupture
- MRCP to characterize. Spyglass or EUS can be useful esp for dysplasia.
- Malig risk - depends on type - 10-30% -
Tx - decompress infection, resect for malig risk
Todani
Type I - ~70-80% - Single dilatation of the extrahepatic ducts
- IA - cystic - IB - focal - IC - fusiform
- Cyst resection and roux en Y hepaticojejunostomy
Type II - 2% - Diverticulum of the extrahep bile ducts
- Simple excision, or resect and hepaticojejunostomy
Type III - 2% - Choledochocele - dilatation of intraduodenal CBD - duod or bil epith
- Treat if symptomatic, sphincterotomy or endoscopic resection
Type IV - 15% - Multiple cysts
- IVA - Both intrahep and extrahep
- IVB - Multiple extrehep
- resect extrahepatic, roux en Y hepaticojejunostomy. May need liver resection for intrahep
Type V - Intrahepatic cysts - Caroli disease
Liver resection or transplant
(Type VI cystic duct - rare - resect)
ABPJ - Consider prophylactic cholecystectomy for risk of GB cancer
FU - consider for incr risk of ca but unclear risk
Caroli disease
- Congenital multifocal dilatations of the large intrahepatic bile ducts
- Can be associated with AR or AD PKD
- Can cause cholangitis, progressive obst, intrahep stones, malig
- Caroli syndrome if portal HTN, Caroli disease if normal CBD
- Imaging - bile duct ectatsia, cystic dilatations segmental dilation in continuity with bile tract , central dot sign foci of contrast, can have PKD, liver bx - not needed - can be used if needed to look for causes of portal HTN
Management - supportive vit ADEK, bone minerals, treat cholangitis, consider ursodeoxycholic acid, treat portal HTN, partial resection or transplant some patients
Bile Duct Injuries
- Iatrogenic Lap chole - 1 in 300
- Rarely other - trauma, radiation, other procedures, scolicidal agents
Risk factors
- Patient - prev op, abnormal anatomy, cirrhosis
- Disease - inflam, mirizzi, loss of Calot, acute, scarring, intra op bleeding
- Surgical - perception 80% - too much fundal, CBD mistaken for cystic, R hepA mistaken for cystic, diathermy, surgeon, equipment, IOC
Often assoc w vascular injury
Prevention
- identify Rouviers - fixed point ventral to the R portal pedicle
- critical view of safety - 2 structures crossing
- IOC - reduction in biliary injuries, identify at time of surgery - identify RPSD
Clinical
- Post op - abdo dist, bloating, ileus, jaundice, biloma, bil peritonitis, fistula and sepsis
- Late - vascular injury ischaemia, strictures, recurrent cholangitis
- ligation of sectoral - atrophy of drained segments, can get infected
- liver failure due to biliary cirrhosis, needing transplantation
Strasberg
- Type A-D for minor duct injuries, Type E is analogous to Bismuth and has 5 types of major duct injuries
- Doesn’t include - vascular, diathermy, timing of injury
- A - Bile leak from cystic duct stump or minor biliary radical in GB fossa
- B - Occluded R posterior sectoral duct
- C - Bile leak from divided R posterior sectoral duct
- D - Bile leak from main bile duct without major tissue loss
- E1 - CBD and low common hepatic duct >2cm from confluence
- E2 - CHD injury <2cm of the hilum
- E3 - Hilar injury, L and R ducts communicating
- E4 - Hilar injury, loss of confluence and separated L and R ducts
- E5 - Stricture of the main CHD and a RPSD
Bile Duct Injury Tx
Work up - LFTs, Bili, ALP - image - CT for collection, MRCP anatomy and leak, CTA for vasc
Management - better outcomes HPB surgeon - primary repair generally doesn’t work.
- drainage - in place or lap washout and place drains
- PTC or ERCP as needed (double PTC in E4)
- nutrition - fat soluble vit def
- aim for 3m delay to definitive repair
Late identification - stricture - ERCP stenting or HJ can be needed
Definitive repair - anat, vasc
- Minor - ligate if small branch
- Under 30% lumen - close w HPB
- Over 30% - HJ - 4.0 PDS roux en Y
Risk - strictures, atrophy, cirrhosis, infected bile
- mortality 6-25%
GB Polyps
Outgrowth of the gallbladder mucosal wall
- neoplastic - adenoma or ca, or non neoplastic - mostly cholesterol which are common
GB polyps - usually asyx incidental - risk up with size (10% 1-1.5cm, 50% over 1.5 and almost all over 2cm)
- Risk age over 60, PSC, sessile, Indian, size
- Echogenic foci on USS
- Tx - syx operate, asyx SRU guideline - over 15mm cholecystectomy, over 2cm stage and HPB
- 5mm or under - only follow up if wall thickening more than 4mm
- 6-14mm
- very low risk ball on wall / thin stalk - 10-14mm - fu 6/12/24m
- low risk - thick stalk - 7-9mm 12m USS, 10-14mm - fu 6/12/24m
- int risk - wall thickening - <6mm fu 6/12/24m - 7mm or over for cholecystectomy
Cholesterolosis
Adenomyomatosis
Porcelain GB
Diffuse cholesterol - strawberry GB of cholesterolosis
Adenomymatosis - benign hypertrohy of GB mucosa, with thickened wall and intramural diverticuli
- Rokitansky Aschoff sinuses - fluid filled mucosal pockets
- cystic structures - necklace on MRI, echogenic and comet tail on USS
- Localised fundus / segmental / annular / diffuse
- No incr risk but can be difficult to tell from GB cancer
- Tx - cholecystectomy if concern or syx
Porcelain Gallbladder - calcification of GB wall
- complete intramural band, or segmental/punctate - most have stones and chronic inflam
- echogenic arc with post shadowing
- rare - risk of malig is likely 2-3%
- Tx - cholecystectomy for syx, and if good candidate / young for risk (controversial)
GB Cancer
Rare, most adenoCa, patterns - infiltrative, nodular, papillary
- early invasion as no submucosa - early LVI, PNI
Risk factors
- Chronic inflam - GS, biliary fistula, APBJ, porcelain GB
- Polyps
- Chronic infections - salmonella, typhoid
- Biliary cysts - APBJ, choledochal cysts
- PSC
- Nitrosamines / carcinogens
Clin - pre, intra, post op
USS - mural thickening, calc, mass
Stage - CT CAP and MRCP - liver invasion, nodal, distant mets
- vasc - PV / triad
- Mets go to peritoneum and liver
GB Ca Stage and Tx
Stage Group - T stage till IIIa, nodes are IIIb and mets IV
T stage
- T1a - tumour just in mucosa
- T1b - invades muscularis (no submucosa)
- T2a - perimuscular tissue - peritoneal side, not serosa
- T2b - perimuscular tissue - hepatic side, no liver invasion
- T3 - perforates serosa, or invades liver and/or another adjacent organ
- T4 - invades PV, HepA or 2 or more extrahep organs / structures
N stage - N1 - 1-3 nodes, N2 more than 3 nodes (Locoregional nodes - cystic duct, CBD, HAP, PV)
Management
- T1a - cholecystectomy
- Early GB Ca T1b/T2 - extended cholecystectomy and lymphadenectomy (porta and hepatoduodenal lig)
- Locally advanced T3/T4 - poor prognosis. Ext cholecystectomy and en bloc if able.
- Nodes - 5y OS 30-60% - main nodes are cystic to CBD, PV , post panc, second pathway to coeliac
Preop dx - stage, CT CAP/MRCP, resect if possible
- T1b - Extended cholecystectomy with 2cm margin of liver tissue, hepatoduodenal lymphadenectomy
- Liver tissue IVb and V. Assess cystic duct with frozen section. +/- more bile duct or liver resection
Intraop dx - high suspicion
- avoid bile spillage and bx, HPB review, consider frozen section
- consider convert to open and extended cholecystectomy
- if not HPB - simple cholecystectomy if committed, if not bail out
Post op dx - incidental - often better prognosis
- Stage, refer MDM - reoperate for T1b - liver resection and lymphadenectomy - high rates residual - wait 4-8 weeks. (Lap port sites don’t need to be resected)
Adjuvant - 5FU chemo - T1b and over (or nodes/margins/palliative)
Immunotherapy - durvalumab anti PD1, and for dMMR
OS at 5y 20%
Unresectable - palliation - pain, jaundice, prolong life
- PTC, ERCP stent, palliative bypass GOO / biliary
- Pall chemo or targeted.
SOD
Anat - 3 parts - sphincter ampullae, sphincter pancreaticus, sphincter choledochus
SOD - abnormal SOD contractility causing functional obstruction
Usually an issue post cholecystectomy - middle aged females most common.
Aetio - hypertonic sphincter / dyskinesia - functional disorder
Hogan-Geenen system - 4 factors
- biliary pain
- ALT/AST/ALP elevated at least once
- bile duct over 10mm
- SOD mannometry
Groups - indicate chance of relief with sphincterotomy
- Group 1 - Pain and 3 criteria - 90%
- Group II - Pain and 1-2 criteria - 85% if SOM abnormal, 35% if normal
- Group III - Pain and no criteria - 55% if SOM abnormal, under 10% if normal
Work up - LFTs, SOD manometry via ERCP - abnormal if over 40mmHg or if paradoxical rise due to CCK
HIDA scan - hepatic IDA - Technetium iminodiacetic acid or analog
- After admin of CCK the GB should contract, ejection fracture over 38% at any time point is normal,
- Under 35% at 20min GB dyskinesia consider cholecystectomy
Tx - nifedipine to decrease sphincter pressure.
- ERCP - Group I and for II and III if pressure up
- 50-90% improve after tx, low rates with type III
PSC
Idiopathic progressive obliterative fibrosis of the medium and large ducts of the biliary tree
- Characterised by inflammation, fibrosis and stricturing
- Linked to UC up to 90%
Histo - Periductal fibrosis concentric replacement by connective tissue in an onion skin pattern
Prognosis - transplant free survival 10y
Clin - asyx, can have fatigue, jaundice, LFT derangement, hepatomegaly
Image MRCP - beaded appearance multifocal short strictures alternating with normal / mildly dilated segments.
- Look for Ca, including in GB
- Bx not usually needed
- Ddx - secondary cholangitis - chemo, trauma, cholangica, IgG4
Stages I-IV as for PBC - I - triad enlargement, scarring, II - parenchymal fibrosis, III - bridging fibrosis, IV - cirrhosis
- Can use elastography
Tx - Goes on to cholestasis, cirrhosis, liver failure - ADEK loss
- 15% cancer risk - cholangioca and GB
- Mayo risk score - Age, Bili, Alb, AST, Variceal bleeding
- MELD
- Medical - ursodeoxycholic acid, steroid, immune suppression
- Endo - stricture tx
- Liver transplant
RPSD
Huang
- 1 - RPSD joins RASD - 75%
- 2 - RPSD triple confluence
- 3 - RPSD into L
- 4 - RPSD into CHD
- 5 - RPSD into cystic duct.
Cystic Duct
Cystic duct
- Angular normal 75%
- Long cystic - 20%
- Spiral cystic - 5%
- Dual, bifurcating
Cystic Artery
R hepatic - most common - posterior to CHD, across hepatocystic
Aberrant - 5%
- Left hepatic, HAP, CHA
- GDA
- Coeliac
- Variant R hepatic
- SMA
Accessory - 5%
- From R hepatic
- From HAP, CHA, L hep
- GDA
Enterohepatic circulation
Bile acids made in liver from cholesterol - cholic acid
- conjugated into bile salts, secreted into gut, modified into secondary bile salts
- most resorbed in ileum as cycle
Action
- preserves most bile acids, but can excrete excess
- for absorption of fat, fat soluble vitamins ADEK and drugs
- helps control water movement
Bilirubin - from haem breakdown from RBC/haem prot
- to green then orange biliverdin
- bilirubin circulates bound to albumin to protect organs
- conjugated in liver, secreted into bile, into GIT
- deconjugated and oxidized in the gut - urobilinogens
- resorbed in enterohepatic circulation
