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