MRCPMRCP vs.vs. ERCPERCP SteveSteve Harrell,Harrell, MD,MD, MSPHMSPH AdvancedAdvanced TherapeuticTherapeutic EndoscopyEndoscopy DecemberDecember 6,6, 20072007 University of Louisville InitialInitial ThoughtsThoughts ““So,So, itit isis mymy predictionprediction thatthat MRCPMRCP willwill havehave aa hugehuge effecteffect onon ERCPERCP practicepractice inin thethe UnitedUnited States.States.”” ““IfIf II hadhad aa pancreaticpancreatic oror biliarybiliary problemproblem II wouldwould searchsearch outout …… aa centercenter withwith thethe mostmost sophisticatedsophisticated noninvasivenoninvasive techniquestechniques…… veryvery quickly.quickly.”” ““WeWe allall wantwant thethe bestbest forfor ourour patients;patients; shouldshould wewe treattreat themthem differentlydifferently thanthan wewe wouldwould ourselves?ourselves?”” 5/15/985/15/98 Peter B. Cotton, MD, FRCP Medical University of South Carolina Charleston, South Carolina Universityhttp://www.ddc.musc.edu/ddc_pro/pro_development of Louisville /hot_topics/impact_MRCP-cotton.htm LearningLearning GoalsGoals KnowKnow whatwhat ERCPERCP andand MRCPMRCP standstand forfor AdvantagesAdvantages andand disadvantagesdisadvantages ofof MRCPMRCP IndicationsIndications forfor ERCPERCP PoorPoor IndicationsIndications forfor ERCPERCP ClinicalClinical UseUse inin commoncommon disordersdisorders forfor MRCPMRCP EffectsEffects ofof MRCPMRCP onon ERCPERCP inin trainingtraining CasesCases University of Louisville ERCPERCP EndoscopicEndoscopic retrograderetrograde cholangiopancreatographycholangiopancreatography (en(en--dohdoh--SKAHSKAH--pikpik REHREH--trohtroh--graydgrayd kohkoh--LANLAN--jeejee--ohoh--PANGPANG--kreekree--uhuh--TAHTAH--gruhgruh-- feefee)) University of Louisville MRCPMRCP MyMy RectumRectum CanCan’’tt PoopPoop ““MRCPMRCP”” asas aa typetype ofof snakesnake MagneticMagnetic resonanceresonance cholangiopancreatographycholangiopancreatography University of Louisville herpherp--ll--humilishumilis--athath--MRCPMRCP--hshs WESTERNWESTERN THREADSNAKETHREADSNAKE University of Louisville MRCPMRCP NonNon--venomousvenomous snakesnake foundfound inin ArizonaArizona NaeemUniversity Knows Snakes! of Louisville INTRODUCTIONINTRODUCTION MagneticMagnetic resonanceresonance cholangiopancreatographycholangiopancreatography (MRCP)(MRCP) isis aa noninvasivenoninvasive techniquetechnique forfor evaluatingevaluating thethe intrahepaticintrahepatic andand extrahepaticextrahepatic bilebile ductsducts andand thethe pancreaticpancreatic duct.duct. Barish, MA, Yucel, EK, Ferrucci, JT. Magnetic resonance Universitycholangiopancreatography. N Englof J Med Louisville1999; 341:258. IntroIntro UnlikeUnlike conventionalconventional endoscopicendoscopic retrograderetrograde cholangiopancreatographycholangiopancreatography (ERCP),(ERCP), MRCPMRCP doesdoes notnot requirerequire contrastcontrast materialmaterial toto bebe administeredadministered intointo thethe ductalductal system.system. Thus,Thus, thethe morbiditymorbidity associatedassociated withwith endoscopicendoscopic proceduresprocedures andand contrastcontrast materialsmaterials isis avoided.avoided. However,However, MRCPMRCP doesdoes notnot currentlycurrently allowallow anyany interventionintervention toto bebe performed,performed, suchsuch asas stonestone extraction,extraction, stentstent insertion,insertion, oror biopsy.biopsy. University of Louisville MRCPMRCP INTROINTRO FirstFirst describeddescribed byby WalnerWalner etet alal inin 19911991 MRCPMRCP isis basedbased onon aa heavilyheavily T2T2 weightedweighted pulsepulse sequencesequence whichwhich showsshows stationarystationary fluids,fluids, suchsuch asas bile,bile, toto appearappear atat highhigh signalsignal intensintensityity whereaswhereas thethe surroundingsurrounding liverliver andand flowingflowing bloodblood generatesgenerates littlelittle signal.signal. AsAs aa resultresult ofof thisthis combinationcombination ofof imagingimaging characteristics,characteristics, MRCPMRCP providesprovides optimaloptimal contrastcontrast betweenbetween thethe hyperintensehyperintense signalsignal ofof thethe bilebile andand thethe hypointensehypointense signalsignal ofof backgroundbackground tissue.tissue. University of Louisville PlainPlain EnglishEnglish StationaryStationary oror slowslow--flowingflowing fluidfluid withinwithin thethe bilebile andand pancreaticpancreatic ductsducts appearappear veryvery brightbright relativerelative toto thethe lowlow signalsignal intensityintensity producedproduced byby adjacentadjacent solidsolid tissuestissues darkdark WithWith thethe specificspecific imageimage acquisitionacquisition sequencessequences used,used, flowingflowing bloodblood hadhad littlelittle oror nono measurablemeasurable signal;signal; asas aa result,result, bloodblood vesselsvessels werewere notnot mistakenmistaken forfor bilebile oror pancreaticpancreatic ducts.ducts. TheThe ductsducts couldcould bebe visualizedvisualized fromfrom multiplemultiple projections,projections, therebythereby duplicatingduplicating cholangiographiccholangiographic imagesimages noninvasively.noninvasively. Bret, PM,University Reinhold, C. Magnetic resonance cholofangiopancreatography. Louisville Endoscopy 1997; 29:472. ExampleExample MRCPMRCP University of Louisville LimitationsLimitations TheThe mainmain potentialpotential problemsproblems withwith MRCPMRCP areare imageimage artifactsartifacts andand difficultydifficulty inin patientpatient compliance.compliance. ImageImage artifactsartifacts cancan bebe producedproduced byby aa brightbright signalsignal arisingarising fromfrom stationarystationary fluidfluid withinwithin thethe adjacentadjacent duodenum,duodenum, duodenalduodenal diverticulaediverticulae,, andand asciticascitic fluid.fluid. InIn addition,addition, locallocal areasareas ofof dropoutdropout ofof signalsignal cancan bebe causedcaused byby metallicmetallic clipsclips followingfollowing cholecystectomy,cholecystectomy, crossingcrossing defectsdefects inducedinduced byby ththee rightright hepatichepatic artery,artery, oror fromfrom severelyseverely narrowednarrowed ducts,ducts, suchsuch asas occursoccurs withwith primaryprimary sclerosingsclerosing cholangitischolangitis (PSC).(PSC). TheThe presencepresence ofof metalmetal leadsleads oror fragmentsfragments precludesprecludes anyany MRMRUniversity imagingimaging study.study. of Louisville LimitationsLimitations Currently, MRCP has lower resolution than direct cholangiography and can miss small stones (<4 mm), small ampullary lesions, primary sclerosing cholangitis, and strictures of the ducts. MRCP also has difficulty visualizing small stones in the pancreatic duct. Certain anatomic characteristics or disorders can mimic bile duct obstruction or common bile duct stones. Obstructing stones are generally easier to identify than nonobstructing stones (especially if smaller than the thickness of the acquired image slices). Small stones may not be distinguishable from sludge, mucin, or even blood. University of Louisville AdvantagesAdvantages andand DisadvantagesDisadvantages MRCPMRCP University of Louisville AdvantagesAdvantages ofof MRCP:MRCP: NonNon invasiveinvasive (avoids(avoids complicationscomplications ofof diagnosticdiagnostic ERCPERCP oror PTC)PTC) NoNo sedationsedation usuallyusually requiredrequired NoNo iodinatediodinated intravenousintravenous contrastcontrast (avoids(avoids iodineiodine anaphylaxisanaphylaxis andand contrastcontrast nephropathy)nephropathy) RapidRapid scanscan timetime NoNo ionizingionizing radiationradiation (safe(safe inin pregnancypregnancy andand children)children) DelineatesDelineates ductalductal anatomyanatomy proximalproximal toto obstructionsobstructions DelineatesDelineates anatomyanatomy postpost biliarybiliary--entericenteric anastomosisanastomosis T1T1 imagesimages definedefine extraductalextraductal structuresstructures (useful(useful inin stagingstagingUniversity malignancy)malignancy) of Louisville http://www.ddc.musc.edu/ddc_pro/pro_development/hot_topics/impact_MRCP.htm DisadvantagesDisadvantages ofof MRCP:MRCP: AddedAdded costcost toto therapuetictherapuetic ERCPERCP (but(but maymay preventprevent diagnosticdiagnostic studies)studies) DuctDuct imagesimages maymay bebe obscobscuredured byby otherother fluidfluid filledfilled structuresstructures (renal(renal cysts,cysts, ascites,ascites, pseudocysts)pseudocysts) ContraindicatedContraindicated afterafter ferromagneticferromagnetic implantsimplants ((eg.pacemakereg.pacemaker,, anuerysmanuerysm clips)clips) ArtifactsArtifacts fromfrom implantsimplants (metal(metal stents,stents, TIPS,TIPS, surgicalsurgical clips)clips) ClaustrophobiaClaustrophobia inin somesome patientspatients ?? LackLack ofof standardizedstandardized scanningscanning protocolsprotocols http://www.ddc.musc.edu/ddc_pUniversityro/pro_development/hot_t of Louisville opics/impact_MRCP.htm IndicationsIndications forfor ERCPERCP University of Louisville University of Louisville http://www.askasge.org/uploadedFiles/Publications_and_Products/Practice _Guidelines/2000_appropriate.pdf ERCPERCP IndicationsIndications contd.contd. University of Louisville University of Louisville ClinicalClinical UseUse MRCPMRCP providesprovides accurateaccurate depictiondepiction andand measurementsmeasurements ofof thethe bilebile andand pancreaticpancreatic ductsducts inin 9595 percentpercent ofof examinations;examinations; associatedassociated anatomicanatomic variants,variants, suchsuch asas pancreaspancreas divisumdivisum andand choledochalcholedochal cysts,cysts, cancan