SUSPECTEDBILIARYOBSTRUCTION-
MRCP,EUSORERCP?
Dr. Yuk Tong LEEMBChB, MD(CUHK), FRCP (Edin), FRCP(Lond), FHKCP, FHKAMSpecialist in Gastroenterology and Hepatology
THEASYMPTOMATICDILATEDCBD
• Thecommonlyacceptedupperlimitofnormaldiameterforthe
mainbileductis4mmto5mminUSstudy
• AdkinsRB,Surg Clin NorthAm2000
Bachar GN, J Ultrasound Med 2003Urquhart P, Gastrointest Endosc 2012
Bile duct diameter according to age (measured by US)
Faris I, Br J Surg 1975; Hunt DR, Australasian Radiol 1996; Urquhart P, Gastrointest Endosc 2012
Bile duct diameter and probability of choledocholithiasis
ASYMPTOMATICALLYDILATEDCBD• ProspectivestudywithERCPon49patientswithoutpreviousupperabdominalsurgeryincluding
cholecystectomyorjaundice
• AtUS,internalCBDdiameter>7mmwithoutanobviouscause
• AtERCP:
• Nolesion41%
• JDD23%
• Benignstricture21%
• DistalCBDmass4%
• Choledochalcyst4% }
• Choledochalcyst+AUPBD:4% } 12%
• AUPBD4% }
• Nostatisticaldifferenceinage,ALPorGGTlevelsbetweenpatientswithandwithoutcausativelesionsatERCP
Kim JE, Endoscopy 2001
GSANDCHOLEDOCHOLITHIASIS
• 15%ofpatientswithGSalsohaveCBDstones.
• ThepresentationofCBDstonedependsonitslocation.
Norton J. Greenberger, Gustav Paumgartner. Chapter 305. Diseases of the Gallbladder and Bile Ducts. Harrison’s Internal Medicine, 17 Ed.
Barkun AN. Endoscopy and gallstones. In: Cotton PB, Tytgat GN, Williams CB (eds). Annual of Gastrointestinal Endoscopy. London: Current Science Limited; 1995: 89±99
LOWPREDICTABILITYOFCLINICALPARAMETER
• 463patientsdefinedpre-interventionasatintermediateorhighrisk
• Overallcholedocholithiasiswasfoundin52%
• Highrisk66.4%,intermediaterisk44.2%
Buscarini E, Gastrointest Endosc 2003
• 64 patients• Overall CBD stones found in 31% • High risk group - 70% found to have stone (only 36%
identified by US/CT)• Moderate risk – 28%, intermediate risk – 4%, low risk - 0%
Canto MI, Gastrointest Endosc 1998
CBDSTONEPREDICTION
• ProspectiveDutchmulti-centrestudyinpredictingCBDstoneinpatientwithacute
biliarypancreatitis(ABP)
• 167patientswithABP– earlyERCP(<72hoursaftersymptomonset).Result
comparingwithUSand/orCTandLFTresult.
• Result:94(56%)severeABP,51(31%)exhibitedadilatedCBDand15(9%)had
CBDstonesonUSstudy.
• CBDstoneswerefoundin89/167patients(53%).
• AlltestedparametersshowedpoorPPV (rangingfrom0.53to0.69)andpoorNPV
(rangingfrom0.46to0.67)inpredictingthepresenceofCBDstone.
H. C. van Santvoort, et al. the Dutch Pancreatitis Study Group. Endoscopy 2011
CHOLEDOCHOLITHIASIS
• Ultrasound
– Variablestonevisualisation(13-75%)
– Dilatedducts(64%)
– Normalsizeducts(36%)
– Nostoneingallbladder(11%)
(HELICAL)CT
N Sen Spec Accuracy
Neitlich, Radiology 1997 51 88% 97%
Kwon, Ann Surg 1998 387 85% 97%Polkowski, Gut 1999 52 85% 88% 86%Soto, AJR, 2000 51 92% 92%
Lee, Abdom Imaging 2006
IHDCBD
1090 73%71%
98%97%
Impaired accuracy when jaundice
MRCP• Meta-analysis,67studies- 4711patients.
• Pooledsensitivity(95%)andspecificity(97%)
• Lesssensitiveforstones(92%)andmalignantconditions
(88%)thanforthepresence(99%)andlevel(96%)of
biliaryobstruction
• Sensitivityofstonedecreasedto62%whenstone<5mm
Romagnuolo J, Ann Intern Med 2003; Boraschi P, Magn Reson Imaging 1999
MRCPAFFECTEDBYBMI
• N=185forMRCPforCBDstone
• OverallMRCPsensitivity81.7%,specificity74.3%
Coban G, Am J Med Sci 2013
Sensitivity Specificity Accuracy
Normal weight 85.2% 93.8% 88.3%
Overweight 75% 65.5% 71.6%
Obese 88.9% 72% 81.9%
ERCP
• SensitivityandaccuracyofERCPindiagnosingbileductstone>90%
• Minutestonemaybemaskedbycontrast,especiallyindilatedduct
• GoodstandardshouldbeERCPplusES
• In119patients,78(66%)CBDstonefound,8(10%)onlyaftersphincterotomy.
Prat F, Gastrointest Endosc 2001
Prat F, Lancet 1996
ENDOSCOPICULTRASONOGRAPHY(EUS)
• Combinesbothendoscopicandultrasonicexaminationinone
• HighfrequencyUSGtransducerused
• Echoendoscope(5– 6– 7.5– 10Mz)
• Intraductalultrasound(12– 20– 30MHz)
• Closeproximitytothebileduct,pancreasandpancreaticdust,
andampulla
• Highlyaccurateindiagnosingbiliary,pancreas,gallbladder,
andampullalesions
DIAGNOSISOFCHOLEDOCHOLITHIASIS BYEUS
97%100%91%95%100%MRCP/Surgery/
ERCP
43De Ledinghen(GI Endo 99)
94%93%94%98%84%ERCP64Canto MI(GI Endo 98)
99%98%100%100%96%ERCP155Sugiyama M(GI Endo 97)
78/119(66%) CBD stones found8 (10%) cases only diagnosed after ES
95%89%99%98%93%ERCP+ES
119Prat F(Lancet 96)
Retrospective study93%98%88%89%97%Surgery/ERCP
422Pallazzo L(GI Endo 95)
13/22 stones <1cm, 14 nondilated bile duct
97%100%100%97%Surgery/ERCP
62Amouyal P(Gastro 94)
USG/CT (Sen): 80/83% 97%100%100%Surgery/ ERCP
52Amouyal P(Lancet 89)
RemarkAccuracyNPVPPVSpecSenEUS vs.NStudy
THEASYMPTOMATICDILATEDCBD
• Prospectivestudyof985patients.90patientswithCBDdilatation(≥7mm)withoutcausativelesionatUS
• EUSprovidedanaccurateexplanationin70patients
• Choledocholithiasis(n=40)
• Benigndistalstricture(n=8)
• Ampullarytumour(n=6)
• Distalcholangiocarcinoma(n=5)
• Pancreaticcancer(n=2)
• Choledochalcyst(n=2)
• Ascaris(n=1)
Songur Y, J Clin Gastroenterol 2001
MRCP
• Sensitivitydecreasedfrom100%to64%whenstones>and<3mmwerecompared. Mendler,AmJGastro1998
• Sensitivitydecreasedfrom100%to62%incomparisonsofstones>and<5mm.Boraschi,MagnResonImaging1999
• EUS• Theaccuracyisnotaffectedbythestoneorbileductsize.
• SugiyamaM,GIEndosc.1997
• TandonM,AmJGastro.2001
MRCPVSEUSFORBILEDUCTSTONE
• Medlinesearch,5randomized,prospective,blindedtrials• Goldstandard:ERCPorIOcholangiography
EUS (95% CI) MRCP (95% CI)Sensitivity 0.93 (0.87-0.98) 0.85 (0.77-0.93)Specificity 0.96 (0.91-1.0) 0.93 (0.88-0.98)PPV 0.93 (0.87-0.99) 0.87 (0.79-0.94)NPV 0.96 (0.94-0.98) 0.92 (0.87-0.96)
LR+ 23.04 (11.6-46.50) 12.14 (7.22-20.43)
LR- 0.07 (0.04-0.15) 0.16 (0.10-0.25)Verma D, Gastrointest Endosc 2006
EUSFORBILIARYOBSTRUCTION– SYSTEMICREVIEW• Notaffectedbythebileductsize
• Notaffectedbythestonesize.
• resolutionofEUS(0.1mm)vsMRCP(1.5mm)
• Coulddiagnosebiliarysludgedisease
• LessinvasivethanERCP
• lowcomplicationrate
• highsuccessfulrate
• ImmediatelyproceedtoERCPinthesameendoscopysetting
Verma D, Gastrointest Endosc 2006
Kim KM, J Clin Gastroenterol 2012
EUS AFTER NEGATIVE CT
Kim KM, J Clin Gastroenterol 2012
Bang BW, DIg Dis Sci 2012
WHYMDCTFAILEDTODETECTCBDSTONES?
Cause N (total) = 41
Small stone (<3mm) 19 (46.3%)
Isodensity (cholesterol stone) 18 (43.9%)
Impacted stone 1 (2.4%)
Misdiagnosis 3 (7.3%)
Bang BW, DIg Dis Sci 2012
• Patients suspected to have choledocholithiasis• Categorized as low, moderate, or high probability• EUS within 48 h, If +ve, for ERCP. • N = 179: low risk 48 (26.8%), moderate risk 65 (36.3%), high
risk 66 (36.9%). • EUS CBD stone - 86, ERCP - 79 (92%). • Multivariate analysis - Only CBD diameter predict CBD stone
Dig Liver Dis 2013
18.8%
50.8%
66.7%
% among group
Anderloni A, Dig Liver Dis 2013
Polkowski M, Endoscopy 2007
Polkowski M, Endoscopy 2007
Polkowski M, Endoscopy 2007
EUSVSERCPINSUSPECTEDBILIARYOBSTRUCTION
• Randomizedcontrolledtrial• DerangedLFTandsuspectedtobebiliaryinorigin• -veUSabdomen• Excludedpatientswithpain(butnotfever)• EUS-guidedvsERCP-guidedintervention
• EUSgroup(N=33)• +veEUS→ERCP+sphincterotomy• -veEUS→observefor1year
• ERCPgroup(N=32)• DiagnosticERC+ve→sphincterotomy• DiagnosticERC–ve→observefor1year
Lee YT, Gastrointest Endosc 2008
• 3(9.4%)hadfailedERCPandallEUSweresuccessful.
• EUSgroup- 9(27.3%)hadbiliarylesions,alltreatedbyERCP
• Nodifferencesbetweentheconvertedandnonconvertedpatientsintheclinicalparameters
• IntheERCPgroup,7(22%)hadbiliarylesionsdetectedandtreated.
• Only30%ofthose“high-risk”patientswasfoundtohavepositivebiliarylesions
Lee YT, Gastrointest Endosc 2008
EUS vs ERCP in suspected biliary obstruction
EUS (n=33) ERCP (n=32)
Sphincterotomy 9 (Converted to ERCP) 14
Complications 2 4Recurrent biliary symptom 1 1
Cholecystectomy 1 3
Death within 1 yearPneumoniaESRFSLE with multi-organ failureLymphoma
211
52111
Lee YT, Gastrointest Endosc 2008
EUS vs ERCP in suspected biliary obstruction
• WithEUSusedasatriagetool,diagnosticERCPanditsrelatedcomplicationscouldbesparedin49(75.4%)patients
Petrov MS, Br J Surg 2009
Petrov MS, Br J Surg 2009
• RCT, medical effectiveness trial in a ‘ real-life setting’
• ERCP first (N=126) vs MRCP first (N = 131)
• A cause of obstruction was found in 39.7% vs. 49.6% (P = 0.11).
• 66 (50%) patients in the MRCP group avoided an ERCP
• Away from daily activities: ERCP group 3.4 ± 7.7 days vs MRCP group 2.0 ± 4.8 days (P < 0.001)
• Additional diagnostic or therapeutic tests: ERCP group 39 (31.0%) patients vs MRCP group 77 (58.8%) patients (P < 0.0001)
MRCP vs ERCP in intermediate risk of biliary obstruction
Bhat M, Aliment Pharmacol Ther 2013
MRCP vs ERCP in intermediate risk of biliary obstruction
• The time delay from MRCP
to ERCP may account for
some of the complication
Bhat M, Aliment Pharmacol Ther 2013
• 11 months prospective study in AED.
• Blood test and US abdomen to stratify risk of CBD stone
• N = 80, 40 patients EUS ± ERCP same session vs 40 patients with EUS done and ERCP in another sessions if needed
• CBD stone: Single session group 25 vs double session group 22, all removed.
Fabbri C, J Gastroenterol Hepatol 2009
Fabbri C, J Gastroenterol Hepatol 2009
• Retrospective review, N = 151
• Group A single session (N = 71)
• Group B separate session (N = 80) - median time from EUS to
ERCP was 7 days (range 2-97 days).
• Comparable baseline demography
Benjaminov F, Surg Endosc 2013
Benjaminov F, Surg Endosc 2013
CONCLUSION
SUSPECTEDBILIARYOBSTRUCTION
• Afterultrasoundandbloodtest
• Highrisk- EUSbeforeERCPordirectERCP
• Moderaterisk- EUSorMRCP;iflesionisfound,goforERCP
• Lowrisk- Nofurtherimaging;orEUS/MRCP