CT胆囊镜

POBox2345,Beijing100023,ChinaWorldJGastroenterol2004;10(8):1204-1207Fax:+86-10-85381893WorldJournalofGastroenterologyE-mail:wjg@wjgnet.comwww.wjgnet.comCopyright©2004byTheWJGPressISSN1007-9327•CLINICALRESEARCH•CTbiliarycystoscopyofgallbladderpolypsMing-WuLou,Wei-DongHu,YiFan,Jin-HuaChen,Zhan-SenE,Guang-FuYangMing-WuLou,Wei-DongHu,YiFan,Jin-HuaChen,Zhan-SenE,Guang-FuYang,DepartmentofRadiology,LonggangCentralHospitalofShenzhenCity,Shenzhen518116,GuangdongProvince,ChinaSupportedbytheScientificBureauofShenzhenCity,No.200006012Correspondenceto:Dr.Ming-WuLou,DepartmentofRadiology,LonggangCentralHospitalofShenzhenCity,Shenzhen518116,GuangdongProvince,China.mingwulou@sina.comTelephone:+86-755-84809409Fax:+86-755-84802448Received:2003-08-06Accepted:2003-10-07AbstractAIM:CTvirtualendoscopyhasbeenusedinthestudyofvariousorgansofbodyincludingthebiliarytract,however,CTvirtualendoseopyindiagnosisofgallbladderpolypshasnotyetbeenreported.ThisstudywastoevaluatethediagnosticvalueofCTvirtualendoscopyinpolypsofthegallbladder.METHODS:Thirty-twocasesofgallbladderpolypswereexaminedbyCTvirtualendoscopy,ultrasound,CTscanwithoralbiliarycontrastseparatelyandconfirmedbyoperationandpathology.CTbiliarycystoscopicfindingswereanalyzedandcomparedwiththoseofultrasoundandCTscanwithoralbiliarycontrast,andevaluatedincomparisonwithoperativeandpathologicfindingsinallcases.RESULTS:Thedetectionrateofgallbladderpolypswas93.8%(90/96),96.9%(93/96)and79.2%(76/96)forCTcystoscopy,ultrasoundandCTscanwithoralcontrast,respectively.CTbiliarycystoscopycorrespondedwellwithultrasoundaswellaspathologyindemonstratingthelocation,sizeandconfigurationofpolyps.CTendoscopywassuperiortoultrasoundinviewingthepolypsinamorepreciseway,3dimensionallyfromanyangleinspace,andshowingthesurfaceindetails.CTbiliarycystoscopywasalsosuperiortoCTscanwithoralbiliarycontrastintermsofobservationofthebaseofpolypsforthepresenceofapedicle,detectionratesaswellasimagequality.ThesmallestpolypdetectedbyCTbiliarycystoscopywasmeasured1.5mm×2.2mm×2.5mm.CONCLUSION:CTbiliarycystoscopyisanon-invasiveandaccuratetechniquefordiagnosisandmanagementofgallbladderpolyps.LouMW,HuWD,FanY,ChenJH,EZS,YangGF.CTbiliarycystoscopyofgallbladderpolyps.WorldJGastroenterol2004;10(8):1204-1207http://www.wjgnet.com/1007-9327/10/1204.aspINTRODUCTIONSinceKleinetal.[1]in1993reportedthecomputedtomographiccholangiographyusingspiralscanningand3Dimageprocessing,manylesionsofthebiliarytracthavebeenstudied[2-14].In1994CTvirtualendoscopy(CTVE)wasintroduced,itsapplicationinobtainingorganimageshasbeendescribedextensively[15-28].However,wehavenotseenanyreportconcerningCTVEinthediagnosisofpolypsofthegallbladder.InthecurrentpaperwereportedtheCTVEfindingsofgallbladderpolypsin32patients.MATERIALSANDMETHODSFromJanuary1999tothepresentstudy,32patientswithgallbladderpolypsconfirmedbyoperationandpathologyunderwentCTbiliarycystoscopy(CTvirtualendoscopeofthegallbladder,CTVEGB).Therewere18malesand14females(agerange,28-47years,meanage,35.8years).Eightpatientshadvaguepainintherightupperabdomen,4patientshadcolickypain,andtheremaining20patientswereasymptomatic.Allpatientshadnormalserumbilirubinandalkalinephosphataselevels.OnthedayofCTVEGB,abdominalultrasonographicstudiesweredoneforallpatients.TheCTscannerwasSomatomplus4powerhelicalCT(Siemens,Germany)withaVirtuosoworkstation(WS).ThesonographicequipmentwascolorDopplerultrasoundHDL5000(ATLUSA).SixteenhourspriortoCTstudy,eachpatienttook4.5gofiopanoicacidsorallyandthegastrointestinaltractwasproperlyprepared.CTscanningparameterswere:120kV,200-220mA,slicethickness2-3mm,pitch1-1.2or1.5-2.0;imagereconstructioninterval:0.8-1.2mmor1.5-2.0mm,FOV214-263mm;scantime25-32s,scanspeed0.75sper360°revolution.ImagepostprocessingwasdonebyDr.Hu.ThereconstructedimagewastransferredtovirtuosoWS.“Fly”softwarewasusedtoobtain3Dstereoimageofthegallbladderandsurroundingstructures,thenvirtualendoscopicimageofthegallbladderwasproceededsimplybydoubleclickonthemouse,thresholdvaluewasadjustedsothatthenormalgallbladdermucosawasdisplayedclearly(Figure1).Thethresholdvaluerangedfrom-178-251HU.Colorencodingwasperformedusinggreencolor(colorofthebile).Endoscopywascarriedoutfromanyviewpointinthegallbladderwithvaryingviews,size,speedandangle,anddetailedscrutinywasperformed.Ittook1htocompleteCTVEGB.AllaxialsourceCTimageswereinterpretedasspiralCTwithoralbiliarycontrast(OCCT)and3DstereoimagesusingflysoftwareasCTVEGB,whichweredonebytworadiologists,whowereunawareoftheclinicalandultrasonographicinformation.Anothertworadiologistsdidultrasonographicstudy.Allradiologistswordedtogetherinevaluatingthenumber,size,configuration,location,surfaceandbaseofpolypsofthegallbladder.Aprofessionalstatisticianperformedallstatisticalanalysesbyusingacommerciallyavailablestatisticalsoftwarepackage(SASInstitute,Cary,Nc).TheresultsofCTVEGB,OCCT,ultrasoundandpathologywerecomparedwitheachotherbymeansofthechi-squaretest.RESULTSOnOCCT,thegallbladderwasclearlyvisualizedin32cases.The3Dstereoviewclearlydisplayedthegallbladderanditssurroundingstructuressuchastheliver,ribsandspineonmaximumintensityprojection(MIP)protocol.CTVEGBimageswereobtainedfromallpatients.Noprocedure-relatedadversereactionwasobservedinall32cases.CorrelationofCTVEGBwithultrasoundThe3Dimage,CTVEGBimage(Figure1A)andaxialsourceimagecouldbedisplayedsimultaneouslyonVirtuosoWS.CTVEGBcouldbemanipulatedflexiblyfrommultipleviewsandvariousanglessothatthelocation,size,configuration,surfaceandbaseofthepolypscouldbeclearlyshownbetteronCTVEGBthanonultrasoundimages.Amongthe32caseswithgallbladderpolyps,thedetectionrateofpolypswas96.9(93/96)byultrasoundand93.8%(90/96)byCTVEGB.ComparisonofultrasoundandCTVEGBwithoperativeandpathologicfindingsisshowninTable1.ThesmallestpolypdetectedbyCTVEGBmeasured1.5mm×2.2mm×2.5mm(Figure1B).Onepolypwithcauliflowerappearance(Figure1C)andanotherbutterfly-likeoneweredetectedbyCTVEGB,whichwereinaccordancewithultrasound(Figure1D)andoperativefindings.Pathologicallybothwereconfirmedtobeinflammatorypolypsofthegallbladder(Figure1E).ComparisonbetweenCTVEGBandOCCTOnOCCT,thegallbladderfilledwithcontrastmediumwaswellvisualized,thepolypsappearedasfillingdetectsofvarioussizesandnumbers.Amongthe96polyps,OCCTdetected76whileCTVEGBdetected90,thedetectionratewas79.2%and93.8%respectively.ThecorrelationwithoperativeandpathologicfindingsisshowninTable2.CTVEGBmissed3polypswithadiameter<3mm,whileOCCTmissed20polypswithadiameter<5mm.Thedifferencewasstatisticallysignificant(P<0.01,a=0.05).CTVEGBandpathologicalclassificationTheincidenceofpolypswasrelatedtothepathologictype.Ofthe90polypsdetectedbyCTVEGB,60werecholesterolpolyps,inwhich12(20%)weresinglecholesterolpolyps(Figure1B)and48(80%)weremultiplecholesterolpolyps(Figure1D).Amongthe30inflammatorypolyps,15(50%)weresinglepolyps(Figure1F)and15weremultipletypes(Figure1C).Thesizeofgallbladderpolypswasrelatedtopathologictypes.Amongthe90polypsdetectedbyCTVEGB,60werecholesterolpolyps,inwhich38(63%)hadthegreatestdiameter5mm,22(37%)hadadiameterof5-10mmand0(0%)hadadiameterof10mm.Therewere30inflammatorypolyps,10(33%)were5mm,8(27%)were5-10mmand12(40%)were10mm.Theconfigurationofpolypswasrelatedtopathologictypes.Amongthe60cholesterolpolyps,52(87%)hadasphericalconfiguration,7(11%)werepapillaryand1(2%)irregularinoutline.Ofthe30inflammatorypolyps,23(77%)weresphericaland7(23%)wereirregularandnonewaspapillaryinform.ThelocationofgallbladderpolypswasFigure1CTVEGBdetectionofgallbladderpolyps.A:SurfacedetailofgallbladderdisplayedbyCTVEGBina47-yearoldnormalman.B:Smallestsinglecholesterolpolyp(arrowhead)detectedbyCTVEGBina28-year-oldman.C:Multiplegallbladderpolypsina30-year-oldman.(1)Multiplepolypsofcauliflowerappearanceandsmallpolyps(arrowhead).(2)Colorultrasonographyfoundmultiplepolypsofcauliflowerappearanceandsmallpolyps(arrowhead).(3)Multiplepolypswereinflammatorypolypsonpathology(HE×20).D:Multiplecholesterolgallbladderpolypsina30-year-oldwoman.Twocholesterolpolyps(arrowhead)wereprovedbypathology(HE×20).E:Singleinflammatorygallbladderpolypsina29-year-oldwoman.Anirregularinflamma-torypolypwasprovedbypathology(HE×20).E2E1D2C2ABC1D1C3LouMWetal.CTstudyofgallbladderlesion1205relatedtopathologictypes.Ofthecholesterolpolyps,40(67%)werelocatedinthebodyofgallbladder,19(31%)intheneckand1(2%)inthebase.Ofthe30inflammatorypolyps,18(60%)werelocatedinthebodyofgallbladder,5(17%)intheneckand7(23%)inthebase.Thepresenceorabsenceofapediclewasrelatedtopathologictype.Therewere36(60%)cholesterolpolypswithapedicleand24(40%)devoidofapedicle.Two(7%)inflammatorypolypswerepedunculatedand28(93%)not.DISCUSSIONAlotoftechniqueshavebeendevelopedforstudyingthebiliarytract.Ultrasonography,thetechniqueofchoiceforstudyingthegallbladder,isoflimitedvalueintheevaluationofpolypsofgallbladder,dependingontheoperator’sskill.Intravenouscholangiographyisasafetechnique,butdoesnotadequatelyopacifythepolypsofgallbladder.Conventionalcomputedtomography(CT)isinadequatefordetectionoflow-densitylesionsofthegallbladder.ERCPandPTCcanprovideexcellentdelineationofbiliaryanatomyandpathology,butbothareinvasiveandassociatedwithrisksandcomplications.MRcholangiographyisapopularnoninvasivetechniqueandhasbeenshowntobebothsensitivetoandspecificforvisualizationofvariousconditionsofthebiliarytract.Althoughitissafe,thetechniqueiscontraindicatedinpatientswithaneurysmclipsorcardiacpacemakers.Inaddition,MRcholangiographymaynotbesuitableforpatientswithclaustrophobiaorthosewithmultiplemetallicclips,whichmaycauseartifacts.Therearefewalternativestotheinvasivetechniques,andadditionalnoninvasivetechniquesareindemand.SpiralCTallowsimagingofavolumeoftissueduringasinglebreath-hold.AxialCTdatacouldbereconstructedintotwo-dimensionalmulti-planarorthree-dimensional(3D)volume-renderedimagesusingworkstationsandimage-renderingsoftware[1].ThisCTtechnologycombinedwiththeadministrationofIVcholangiographiccontrastagentscouldproducediagnosticimagesofthebiliarytract[2-7,9,10,14],andhasbeenusedfordiagnosisofobstructivebiliarydisease,choledochocele,choledocholithiasisandaberrancebileducts.Themainlimitationofthistechniqueisthattherateofallergicreactionsandrenalorhepatictoxicity(orboth)arerelativelyhighduetobythesecontrastagents.OralcholangiographiccontrastagentsareapotentialalternativetoIVcontrastagents.Unlikethelater,thesecontrastagentshadfewsideeffects,suchasdiarrhea,loosestools,nauseaandstingingonurination[8].Becausethepatientsingested6giopanoicacidbeforeCTexamination[8,11,13],thecontrastagentsweredecreasedto4.5giopanoicacid.Nosideeffectwasfoundinourstudy.CTcholangiographywasusedtoassesscholedochvariantsanddescribecholedocholithiasis[8,11,13].Toourknowledge,therehavebeenfewstudiesorreportsinwhichIVcholangiograhpiccontrastagentswereusedtodiagnosegallbladderpolyps[10].IthasnotyetbeenestablishedwhethertheseoralcontrastagentscanreliablydemonstrategallbladderpolypsonCTVEGB.SomefactorscouldinfluencetheimagequalityofCTVEGB,whichisimportantforprecisediagnosticinformation.Usually16hafteroraladministrationof4.5giopanoicacid,CTVEGBcouldyieldtheimageofgallbladderwithagoodquality.Withadoseof3.0g,visualizationofthegallbladderwouldbeinadequate.Inadequatecontrolofrespiratorymotionhasadverseimpactonimagequality,resultinginfailuretodetectsmalllesionsorraggeddistortionoflargelesions.Optimalimagequalityisachievedbysinglebreathhold.Higherreconstructionratessuchas0.8-1.2mmaremorehelpfulindisplayingminutelesionsandthedetails.Higherpitch(1.5-2.0)mayproduceartifact-mimickingpolypsormisssmalllesions.Pitch1.0-1.2isagoodchoice.FOVisrelatedtothedisplayedareaofthesurroundingstructuresbutnottoobservationofthepolyps.However,adequateFOVcanclearlydemonstratethestereorelationofgallbladderandsurroundingstructures.Thethresholdvalueseriouslyaffectseffectiveobservationofpolyps.Variationofthethresholdvalueleadstomarkedchangeinvisualizationofthesizeandappearanceofpolyps,thereforeselectingappropriatethresholdvalueiscriticaltoavoidimagedistortion.Generally,athresholdvalueisselectedsothatthenormalgallbladdermucosaisshownclearly.BasedonourclinicalexperienceindiagnosinggallbladderpolypsbyCTVEGB,TVEGBcanclearlydisplaythenormalanatomyoftheinteriorofgallbladder.CTVEGBcanclearlyshowthesize,configuration,location,surfaceandbaseofgallbladderpolypsinaccordancewithcolorultrasound,Table1ComparisonofultrasoundandCTVEGBin96gallbladderpolypsDiameter(mm)Location(n)Configuration(n)Base(n)peduncleModalityPolyps(n)<55-1010-NeckBodyBaseSphericalPapillaryIrregularButterflyCauliflower(-)(+)Pathology96543012246488176115838Ultrasound93513012246187876115538CTVEGB90483012245887576115238c20.4660.4850.4780.4710.482Pvalue>0.05>0.05>0.05>0.05>0.051.Nostatisticalsignificance(P>0.05,a=0.05)betweenultrasoundandCTVEGBfindings;2.CTVEGBisabbreviationofCTvirtualendoscopyofthegallbladder.Table2ComparisonofOCCTandCTVEGBin96gallbladderpolypsDiameter(mm)Location(n)Configuration(n)Base(n)peduncleModalityPolyps<55-1010-NeckBodyBaseSphericalPapillaryIrregularButterflyCauliflower(-)(+)Pathology96543012246488176115838OCCT76343012244486176115224CTVEGB90483012245887576115238c27.5188.5618.1577.74314.797Pvalue<0.01<0.01<0.01<0.01<0.011.StatisticaldifferencebetweenultrasoundandCTVEGBfindings(P<0.01,a=0.05);2.CTVEGBisabbreviationofCTvirtualendoscopyofthegallbladder;3.OCCTisabbreviationofspiralCTwithoralbiliarycontrast.1206ISSN1007-9327CN14-1219/RWorldJGastroenterolApril15,2004Volume10Number8螺距�视场角�operativeandpathologicfindings.Thesmallestpolypreportedinthisarticlewas1.5mm×2.2mm×2.5mm.Localizationofthepolypswasaccurate.Gooddepictionofpolypconfigurationcouldbeobtained.Inthisseries12polypswithirregularappearancewereprovedtobeinflammatoryinnaturewithadhesions.DetailedobservationofthebaseofpolypstoconfirmthepresenceofapediclebyCTVEGBwaspossiblebyviewingfromdifferentanglesandinthisrespect,CTVEGBwassuperiortocolorultrasound.Amongthe96polyps,CTVEGBmissed6polypswiththediameterlessthan3mm.Colorultrasoundmissed3polypsbecauseofadhesionwithsurroundingtissues.Thedifference,however,wasnotstatisticallysignificant(P>0.05).Thecorrespondencewasgood.OCTT,beingasafe,simpleandefficientmethod[1-7],iscapableofdetectingbiliarycalculus,tumor,anomalyanddilatationofthebiliarytractandprotrudinglesionswithabiggersize.However,limitedbytheconcentrationofcontrastmedium,smallpolypouslesionsareeasilyobscuredandthusescapingdetectionbyOCCT.Inthisseries,20polypswithadiameterlessthan5mmweremissed.OCCTisalsoinferiortoCTVEGBintermsofobservationofthebaseofpolypsforthepresenceofapedicle,detectionrateaswellasimagequality.IncomparisonofthefindingsofCTVEGBwithpathologicalchanges,incholesterolpolyps,multiplepolypswerefarmorefrequentlyseenthansinglepolyps(80%vs20%).Whileininflammatorypolyps,theincidencewas50%foreach,indicatingthatmostcholesterolpolypsweremultiple,whilesinglepolypandmultipleoneswereequallycommonininflammatorypolyps.Amongthecholesterolpolyps,63%were5mm,37%werebetween5-10mm,nonewas10mm.Whileininflammatorypolyps,33%were5mm,27%wasbetween5-10mm,40%were10mm,indicatingthatsmallerpolyps(5mm)werecommonincholesterolpolypsandbiggerones(10mm)werecommonininflammatorypolyps.Amongcholesterolpolyps,sphericaltypewasmostcommon(87%),followedbypapillarytype(11%),thenirregulartype(2%).Forinflammatorypolyps,77%weresphericaltype,23%ir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