留学生呼吸胃肠肝胆eng 2017

1RespirationsystemXiaoliLanDepartmentofNuclearMedicineUnionHospital，TongjiMedicalCollegeHuazhongUniversityofScience&TechnologyHubeiKeyLaboratoryofMolecularImaging2methodsbywhichonephysiologicalaspectoflungfunctionisevaluated.Themostwidelyusedtechniquesare:lungperfusionimagingusingtechnetium-99mMAA(macroaggregatesofalbumin)labelledperfusionagents

lungventilationimagingusingeitherradioactiveXenonXeortechnetium-99mlabelledaerosols.Theclinicalindicationsaremainlythediagnosisofpulmonaryembolism.Radionuclidelungimaging3MainContentsPerfusionLungImaging

VentilationLungImagingV/Qscan4PerfusionlungimagingPrinciplePerfusionlungimagingisanoninvasivemethodforevaluatingpulmonaryarterialbloodflow.Theparticlesaretrappedinthecapillarybedofthelungstocreatelungperfusion"map."The300,000particlesadministeredoccludelessthan0.1%ofthetotalcrosssectionofthelungs.5PerfusionlungimagingAgentsAgents:

99mTcMAA(macro-aggregatedalbumin)

99mTcHAM(humanalbuminmicrospheres)

Dose:

4mCiParticles:

size10~90

m

number200,000~500,000effect1:1000arteriolesembolized6PerfusionlungimagingAgentsMaytheParticlesInfluencePulmonaryFunction?Themendednumberofparticlesperinjectionis200,000to500,000whichoccludes1in1500arteriolesinthelung.Theocclusionistransientbecausetheparticlesmaybedegradedintomoresmallerparticles.Soperfusion-lungimagingisanoninvasivemethodforevaluatingpulmonaryarterialbloodflow.7PerfusionlungimagingProcedure

ViewsAnterior(ANT)Posterior(POST)Leftlateral(LL)Rightlateral(RL)

Leftposterioroblique(LPO)Rightposterioroblique(RPO)Leftanterioroblique(LAO)Rightanterioroblique(RAO)PlanarimagingTomographyimaging8PerfusionlungimagingImageinterpretationNormalimageYoucanseeviewsobtainedfrombothanteriorandposterioraswellaslateral.Thedistributionofradiotracerishomogeneousandnon-interrupted.9PerfusionlungimagingImageinterpretationInnormalsubjects,thepatternsofperfusionlungscanareinfluencedbyage,changesingravity,anddepthofrespiratoryeffort.Evenasmall,ill-definedperfusiondefectmaybeclinicallysignificantina

youngpatientwhileitwouldbeconsideredinsignificantina

middle-aged

patient.Becauseoftheinfluenceof

gravity,regionalbloodflowofupperlobeislowerandthelowerlobeishigherifthepatientwasinjectedinsittingposition.Andtheposteriorzonesarehigherifthepatientwasinjectedinsupineposition.10PerfusionlungimagingImageinterpretationPlanarnormalimage111apical2posterior3anterior

RightupperlobeRightmiddlelobe4lateral5medialRightlowerlobe6superior7medialbasal8posteriorbasal9lateralbasal10anteriorbasal15superior16posteriorbasal17lateralbasal18anteriormedialbasalLeftupperlobe11apicalposterior12anterior13superiorlingular14inferiorlingularLeftlowerlobe12PerfusionlungimagingImageinterpretation1314PerfusionlungimagingImageinterpretationAbnormal15Case:

Thispatientexperiencedsuddenonsetofshortnessofbreath.Youcanseesignificantareasthatarenotperfused–thereareatleast8segmentsnotperfused16MainContentsPerfusionLungImagingVentilationLungImaging

17ventilationlungimagingPrincipleVentilationlungimagingisundertakenusingradioactiveXenon(氙气)oraerosol(气溶胶)forwhichthepatientbreathesthroughaclosedgasdeliverysystem.Uponradiolabeledgasintothedeliverysystem,itstarts

tobetakenintothelungs.Furtherimagingisdoneduringequilibrium.

Finallythesystemisopenedtoroomairduringinhalationwhichleadstothewash-outoftheradioactiveXenonoraerosol.18ventilationlungimagingAgents133Xe

mostcommonlyused

127Xe81mKr(Krypton)

veryexpensive99mTc-DTPAaerosol

Gas-ventilationImagingAerosol-ventilationImaging19ventilationlungimagingAgentsComparisonbetweengasand

aerosol-ventilationImagingGas-ventilationimagingcandetectregionsofairwayobstructionbyshowingretentionofthegasduringtheclearancephase.Aerosol-ventilationimagingcouldnotshowsuchretention,butcanallowadirectcomparisonofperfusionandventilationinmultipleviews.20Procedure21ventilationlungimagingImageinterpretationNormalGas-ventilationImagingInspirationExpirationWashoutEquilibrium22ventilationlungimagingImageinterpretationlarynx23ventilationlungimagingImageinterpretation24ventilationlungimagingImageinterpretationnormaltrachea25ventilationlungimagingImageinterpretationnormalStomach26V/QscanClinicalapplicationsDiagnosisofPE

(PulmonaryEmbolism)DiagnosisofCOPD

(chronicobstructivepulmonarydisease)27ClinicalapplicationsPulmonaryEmbolismPulmonaryembolism(PE)isacommonandpotentiallylethaldisease;unfortunately,thediagnosisisoftenmissedbecausepatientswithPEpresentwithnonspecificsignsandsymptoms.28PulmonaryEmbolismClinicalapplicationsAlthoughangiographyhashighsensitivityandspecificityindiagnosisofPE,itisexpensiveandinvasive.ItisveryimportanttoselectamethodthatisusefulinearlydiagnosisofPE.29V/QscanningofthelungsisanimportantdiagnosticmodalityforestablishingthediagnosisofPE.V/QscancontinuestobethebesttechniqueforexcludingPE.PulmonaryEmbolismClinicalapplicationsA

ventilation/perfusionlungscan,alsocalleda

V/Qlungscan,isatypeof

medicalimaging

using

scintigraphy

and

medicalisotopes

toevaluatethecirculationofairandbloodwithinapatient's

lungs,

inordertodeterminethe

ventilation/perfusionratio.The

ventilation

partofthetestlooksattheabilityofairtoreachallpartsofthelungs,whilethe

perfusion

partevaluateshowwellbloodcirculateswithinthelungs.AsQinphysiologyistheletterusedtodescribebloodflowthetermV/Qscanemerged.30PulmonaryEmbolismClinicalapplicationsLungperfusionimaging

ispositiveassoonasthepulmonaryembolismoccursandisanoninvasiveandsensitivemethod.

Ifperformedinconjunctionwiththelungventilationimaging

orchestradiography,thesensitivityoflungperfusionimagingindiagnosisofPEcouldreachto90%ormore.31PulmonaryEmbolismClinicalapplicationsDiagnosticcriterionsThe

normal

lungperfusionimagesinmultipleviewscan

eliminatethediagnosisofPE.

Multiplesegmentaldefectsinperfusion,butnormalfindingsinventilationimagingorX-rayfilm,indicatingthehighpossibilityofpulmonaryembolism.32PulmonaryEmbolismClinicalapplicationsMATCHVentilationPerfusion33PulmonaryEmbolismClinicalapplications34PulmonaryEmbolismClinicalapplicationsPerfusionVentilationMISMATCH35PulmonaryEmbolismClinicalapplications36PulmonaryEmbolismClinicalapplicationsMATCHVentilationPerfusion37PulmonaryEmbolismClinicalapplications38V/QScanInterpretationResultInterpretationSignificanceNormalNoperfusiondeficitExcludespulmonarythromboembolismLowprobabilityPerfusiondeficitwithmatchedventilationdeficit<20%probabilityofPEIntermediateprobabilityPerfusiondeficitthatcorrespondstoparenchymalabnormalityonchestx-ray20%-80%probabilityofPEHighprobabilityMultiplesegmentalperfusiondeficitswithnormalventilation>80%probabilityofPEPulmonaryEmbolismClinicalapplications39PulmonaryEmbolismClinicalapplicationsVentilation/PerfusionScans

A.VeryLowProbabilityofPulmonaryEmbolism

B.HighProbabilityofPulmonaryEmbolism40PulmonaryEmbolismClinicalapplicationsPerfusionX-ray41PulmonaryEmbolismClinicalapplicationsBeforetreatmentAftertreatment42PulmonaryEmbolismClinicalapplicationsSPECT/CT99mTc-MAACase:male49ywithpulmonaryembolism99mTc-MAADeepVenousThrombosisImaging44COPDClinicalapplicationsCOPDisadisorderthatischaracterizedbyreducedmaximalexpiratoryflowandslowforcedemptyingofthelungs.45COPDClinicalapplicationsNearlymatchedreducedordefects46SummaryandKeyPointsTheprincipleandclinicalapplicationoflungperfusionimagingandventilationimaging.Islungperfusionimagingsafe?Pleasegivereasons.

47GastrointestinalSystemDepartmentofNuclearMedicineUnionHospital，TongjiMedicalCollegeHuazhongUniversityofScience&TechnologyXiaoliLan48MainContents

GastrointestinalbleedingimagingEctopicgastricmucosaimagingGastricemptyingimagingSalivaryglandimaging49GastrointestinalbleedingimagingDetectionandlocalizationofgastrointestinal(GI)bleedinghascometoplayanimportantroleinthemanagementofpatientswithGIhemorrhage.GIbleedingimagingisanestablisheddiagnosticandcomplementarytechniquetoendoscopyandangiographyforthedetectionofGIbleeding.50GastrointestinalbleedingimagingContrastangiographyisthegoldstandardforGIlocalization.However,itisinvasiveandtheremustbeactivehemorrhageatthetimeofcontrastinjectiontolocalizeableedingsite.GIbleedingistypicallyintermittentandtheclinicaldeterminationofwhetherapatientisactivelybleedingisunreliablebecausesymptomsandclinicalfindingsarenotedafterthebleedingisstopped.51GastrointestinalbleedingimagingRadionuclideGIbleedingimagingismoresensitivethancontrastangiographybyafactorof10.GIbleedingimagingcandetectbleedingratesofapproximately0.1ml/min,comparedwithto1cc/minwithContrastangiography.

GIbleedingimaginghastwopurposes:First,itgivesassurancethatthepatientisindeedactivelybleeding.Second,itcanlocalizetheapproximatesiteofhemorrhage,givingtheangiographerinformationonthelikelyvascularoriginofthebleed.52NormalanatomyGIbleeding53AgentsGIbleeding99mTc-RBCimagingacuteorintermittentbleeding

repetitious(longerimagingtime,potentiallyupto24h)dose:555~740MBq99mTc-colloidimaging

clearimage(rapidlyextractedbyreticuloendothelialcellsofliver,spleen,andbonemarrow)

acuteandactivebleedingbutnotintermittentdose:296~370MBq5499mTcsulfurcolloid

99mTcredbloodcells

SLOWERbleedingratesgreaterthanorequalto.05ml/minFASTERbleedingratesgreaterthanorequalto.1ml/minRAPIDLYclearedfromintravascularspaceSTAYSinintravascularspacefor48hrs.ImageimmediatelyImageover24hrs.Mustseebleedingw/infewmin.postinjection

CAN'Tvisualizebleedsnearliver/spleenCANvisualizebleedsnearliver/spleen

POORforintermittentbleedsGOODforintermittentbleedsHIGHERtargettobkgdratioLOWERtargettobkgdratio

SHORTvasculart1/2=2.5-3.5minLONGvasculart1/2=29hrs.GIbleedingAdvantagesandDisadvantages55IndicationsGastrointestinalbleedingstudiesareindicatedinpatientswithknownorsuspectedGIbleedingtodetectthepresenceofbleedingandtolocalizethesiteofbleeding.GIbleeding56ImageInterpretation

---normalGIbleedingOnsulfurcolloidstudies,bloodpoolstructuressuchastheheartandgreatvesselsarevisualizedimmediately.Activityinthesestructuresquicklyfadesasthesulfurcolloidisextractedbytheliver,spleenandbonemarrowandactivityinthesestructuresesmoreintense(NUCIMAGE).Backgroundactivityalsoclearsovertimewhichbetterallowsvisualizationoftheactualbleedingsite.Normalstudiesshownoevidenceoffocallyincreasedtraceractivityonfloworstaticimages.57normalGIbleeding99mTc-RBC58GIbleedingImageInterpretation

---abnormalActiveGIbleeding59ClinicalapplicationsGIbleedingGIbleedingimagingprovidesahighsensitivityforthedetectionofalowbleedingrate,andallowscontinuousmonitoringoftheGItrackforseveralhours.Theprocedureiswelltoleratedandeasytoperform.60MainContentsGastrointestinalbleedingimaging

EctopicgastricmucosaimagingGastricemptyingimaging

salivaryglandimaging61Principle

Basedupontheobservationthat99mTc-pertechnetateisconcentratedandsecretedbythemucussecretarycellsofgastricmucosa,bothnormalandectopic.TheuptakeofTc-99mpertechnetateinanectopicmucosashouldhavethesamecharacteristicsasitsconcentrationinthestomach.Ectopicimaging62Agents

99mTcO4-(Tc-99mpertechnetate)370~555MBq(10-15mCi)Ectopicimaging63ImageInterpretation

---normalEctopicimagingStomachcanbeseenontheimage，butnottheesophagusandintestine.64ImageInterpretation

---abnormalEctopicimagingAdiscretefocusofincreaseduptakeisseenintherightlowerquadrant,withapproximatelythesameintensityasthestomach.65ClinicalapplicationsTodetectMeckel’sdiverticulumTodetectBarrett’soesophagusTodetect

smallintestinerepeatedabnormality.

Ectopicimaging66EctopicimagingCase1:

21/2yearoldboywithaonedayhistoryofbloodystools.POSTRightlateralANTMackerl’sdiverticulum67EctopicimagingCase2:

A20-year-oldmandescribedanacuteepisodeofrectalbleeding(brightred).

68MainContentsGastrointestinalbleedingimagingEctopicgastricmucosaimaging

Gastricemptyingimagingsalivaryglandimaging69

Gastricemptyingimaging

EmptyingstudyAgastricemptyingstudyisaprocedurethatisdonebynuclearmedicinephysiciansusingradioactivechemicalsthatmeasuresthespeedwithwhichfoodemptiesfromthestomachandentersthesmallintestine.Gastricemptyingstudiesareusedfortestingpatientswhoarehavingsymptomsthatmaybeduetoslowand,lesscommonly,rapidemptyingofthestomach.Thesymptomsofslowemptyingareprimarilynausea,vomiting,andabdominalfullnessaftereating.Thesymptomsofrapidemptyingarediarrhea,weaknessorlight-headednessaftereating.70Principle

EmptyingstudyForagastricemptyingstudy,apatienteatsamealinwhichthesolidfood,liquidfood,orboth,aremixedwithasmallamountofradioactivematerial.

Themixedfoodcannotbeabsorbedbythestomachbutcanbeemptiedintotheintestineroutinely.Ascannerisplacedoverthestomachtomonitortheamountofradioactivityinthestomachforseveralhoursafterthetestmeal.71MethodsEmptyingstudyDonoteatordrinkanythingovernightandinthemorning.PatientpreparationMealsSolid:eggs,sandwich,Liquid:water,orangejuice,milkThecompositionofradiolabeledmealsvarieswidely.Mealsaremostoftenlabeledwith99mTc-sulfurcolloid.72ImageinterpretationEmptyingstudyNormalvaluesforthespecificmealshouldbeestablishedbeforetheresultscanbereported.Thereareseveraldifferentmeasurementsconsiderednormal,dependingontheradioactivematerialandsolidmealused.Thevalueisexpressedasapercentageofemptyingoveraperiodoftime.Timeofgastricemptyingisrelatedtosomefactors:gender,time,positionandstatus.73EmptyingstudyNormalimage

—solidfood

0min15min30min45min60min90min120min150min74AbnormalimageEmptyingstudyTimeofgastricemptying----shortenedorprolongedAt1-hour,68%oftheoriginalcontentswerestillpresentinthestomach.At2-hours,57%oftheoriginalcountswerestillpresentinthestomach,andat4-hours,greaterthan50%ofthecontentswerestillleftinthestomach.

Greaterthan10%at4-hoursisconsideredsignificantforgastroparesis(胃麻痹）.75EmptyingstudyClinicalapplication

DelayedgastricemptyingAcceleratedgastricemptyingMechanicalobstruction:tumor,scarFunctionalobstruction:ulcer,gastritis,surgerySurgery,hyperthyoidism,duodenumulcer,ZollingerEllisonSyndrome

76MainContentsGastrointestinalbleedingimagingEctopicgastricmucosaimagingGastricemptyingimaging

Salivaryglandimaging77Principle

SalivaryimagingThesalivaryglandsarefleshlyexocrineglandsthatsurroundtheoralcavityandsecretesalivatoaidthedigestionprocess.Therearethreemajorpairsandnumerousminorsalivaryglands.parotidglandssubmandibularglandssublingualglands78Principle

SalivaryimagingTheabilityofthesalivaryglands'epithelialcellstotransportanions,includingiodideandpertechnetate,fromthesurroundingcapillariesandsecretethemintothesalivaprovidestheprincipleforimagingthesalivaryglandswithTc-99mpertechnetate.Thefunctionalcapabilities,structuralintegrityandlocationoftheglandscanbeassessed.79AgentSalivaryimaging

99mTcO4-(Tc-99mpertechnetate)180~370MBq(5-10mCi)80ProcedureSalivaryimagingPatientPreparationNospecificpatientpreparationStaticImagesWashoutIncludethyroidglandforparisonAdministersalivaryglandstimulant(VitC)followingcompletionofstaticimages81Imageinterpretation---normalSalivaryimagingStaticimagesdemonstratesalivaryglandfunctionWashoutdemonstratessalivaryglandexcretion30min82normalSalivaryimaging83

AbnormalSalivaryimagingNormal30minabnormal15minabnormal30minabnormal60min84

ClinicalapplicationsSalivaryimaginghighfunction:moreincreaseuptakeeg.AcuteSialadenitis(急性涎腺炎)lowfunction:reduceduptakeorevennoimageeg.Sjögren‘sSyndrome(舍格伦综合征)salivaryglandnodules:Coldnodule:WarmnoduleHotnodule:obstruction85

KeypointsPrincipleandclinicalapplicationsfordifferentimagingGastrointestinalbleedingimagingEctopicgastricmucosaimagingGastricemptyingimagingsalivaryglandimaging86LiverandSpleenXiaoliLAN87MainContentsLiverarteryperfusionandbloodpoolimaging

HepatobiliaryimagingSpleenimaging

Livercolloidimaging88PrincipleHepatobiliaryimagingHepatobiliaryimagingisamethodtodiagnoseandevaluatethehepatobiliarydiseases.Forexample,acuteandchroniccholecystitis,biliaryobstruction,bileleaksandsoon.89PrincipleHepatobiliaryimagingHepaticcellssecreteabout1literofbileperday.Bilirubin(胆红素)isextractedfromtheplasmabythehepatocytes,andexcretedintothegallbladder.Theradiolabeledcompoundshavethesamehepaticuptakeandexcretionpathwaysasbile.90AgentsHepatobiliaryimaging99mTc-iminodiaceticacid(99mTc-IDAs)99mTc-pyridoxylideneaminoacid(99mTc-PAA)99mTc-EHIDA99mTc-DISIDA99mTc-mebrofenin91ProceduresHepatobiliaryimagingPatientPreparation

Thepatientmustfastforatleast4hoursbeforethetest.

Recentmeals,aswellasprolongedfasting(>24hours)mayresultinfalse-positiveresults.

Ifpatientshavenoteatenformorethan24hours,pretreatmentwithSincalide(syntheticanalogof

CCK)isnecessary.CCK:cholecystokinin92InterventionTestsHepatobiliaryimagingCholecystokinin(CCK,缩胆囊素):CCKactsonthereceptorswithinthegallbladderwallandcausescontraction,cleaningoutanyremainingsludgeorbilethataccumulateswithinthegallbladder.Indicationspatientfastingformorethan20to24hoursdeterminationofGBEF(gallbladderejectionfraction)93InterventionTestsHepatobiliaryimagingMorphineMorphinecanproduceuptoa10foldincreaseintherestingpressureofthecommonbileductbycausingcontractionofthesphincterofOddi.ThesubsequentriseincommonductpressureisfelttoincreaseflowintoGBunlessthecysticductisobstructed.Morphinecanbeusedtodecreasethetimerequiredtoconfirmacutecholecystitis94ImageInterpretationHepatobiliaryimagingBloodperfusionphase

(30~45s)Liverphase

(1~3min)Bileexcretionphase

(5~45min)Intestinalexcretionphase

(45~60min)95Normal96ImageInterpretationHepatobiliaryimagingIHBD–intrahepaticbileductGB–gallbladderCBD–commonbileductGBIHBDCBD97ImageInterpretationHepatobiliaryimaging98ClinicalapplicationsHepatobiliaryimagingDiagnosisofacutecholecystitis;DiagnosisofChroniccholecystitis;Diagnosisofcongenitalbileductdilatationsyndrome;DiagnosisofcongenitalBiliaryatresia;Diagnosisofgeneralgallbladdertractobstruct;Diagnosisofpletegeneralgallbladdertractobstruct;EvaluationofPost-operativeBiliaryLeaks;Otherdiseases99HepatobiliaryimagingAcutecholecystitisVisualizationofthebiliarysystemwithnon-visualizationofthegallbladderafter4hoursisconsidereddiagnosisofacutecholecystitis.100HepatobiliaryimagingAcutecholecystitisTheoverallsensitivityandspecificityforthediagnosisofacutecholecystitisisgreaterthan95%and98%,respectively.101Acutecholecystitis102HepatobiliaryimagingAcutecholecystitisThenegativepredictivevalueofanormalexam(ie:visualizationofthegallbladderwithin1hour)inexcludingacutecholecystitisisgreaterthan99%.

103HepatobiliaryimagingAcutecholecystitisDifferentialdiagnosis

ofNon-visualizationoftheGBatonehour

RecentmealProlongedfastingover20to24hoursProlongedintravenousnutrition(静脉营养)AcutePancreatitisCommon/CysticductobstructionSeverehepatocellulardysfunction(Hepatitis,Cirrhosis)CongenitallyabsentGB104CCKMorphinedelayedimagingIfthegallbladderisNOTvisualizedat60minutesafterinjection,

threeoptionsexist:HepatobiliaryimagingAcutecholecystitis105HepatobiliaryimagingChroniccholecystitisThemajorityofpatientswithchroniccholecystitisexhibitnormalvisualizationofthegallbladder(85-90%).Delayedvisualizationofthegallbladder(Between1to4hoursoftheexam)isconsideredthecharacteristicforchroniccholecystitisThelongerthedelayinvisualization,thehigherthecorrelationwithchroniccholecystitis.106HepatobiliaryimagingChroniccholecystitisThemaincriteria:Delayedgallbladdervisualization(after60minutes)

Prolongedbiliarytoboweltransit

VisualizationofthesmallbowelBEFOREgallbladdervisualizationatonehourDecreasedgallbladderejectionfractionof<35%107HepatobiliaryimagingChroniccholecystitis108HepatobiliaryimagingChroniccholecystitisGallbladderejectionfraction(GBEF)AnabnormalGBEFisconsideredlessthan35%

andisnotaffectedbyage.

pre-CCKGBcounts-post-CCKGBcountsGallbladderEF=-------------------------------------------------------------------X100%pre-CCKGBcounts109HepatobiliaryimagingCongenitalBiliaryatresia(先天性胆道闭锁)Noimageofintestine110HepatobiliaryimagingCongenitalBiliaryatresia(先天性胆道闭锁)Differencebetweenthecongenitalbilliaryatresiaand

neonatalhepatitis(新生儿肝炎)CongenitalBiliaryatresia:nointestineimage.

phenobarbital(苯巴比妥)test:nointestineimage.Neonatalhepatitis:intestineimage.

phenobarbital(苯巴比妥)test:intestineimage.phenobarbitalcouldincreasetheexcretionofbile111CongenitalBiliaryatresia(先天性胆道闭锁)nointestineimage112neonatalhepatitisTheimageofintestinecanbeseenafter4h----delayedimageofintestine113HepatobiliaryimagingCommonbileductobstruct114HepatobiliaryimagingThehepatobiliarytestdemonstratedpromptuptakeoftheradiotracerwithnoexcretion.Commonbileductobstruct115HepatobiliaryimagingCommonbileductobstruct116DelayedimageOfintestinepletionCommonbileductobstruct117Evaluationofpost-operationofhepatobiliary

（肝胆道手术后的评价）Contraflowofbileandstomach118Evaluationofpost-operationofhepatobiliary

（肝胆道手术后的评价）Leakageofbile119MainContentsLiverarteryperfusionandbloodpoolimaging

HepatobiliaryimagingLivercolloidimagingSpleenimaging

120PrincipleThisstudycanbeusedfordeterminingthesizeandshapeoftheliverandspleenaswellasdetectingthefunctionalabnormalitiesofthereticuloendothelialcellsoftheseorgans.Theradiolabeledsulfurcolloidparticlesarephagocytizedbythe

reticuloendothelialcellswithanextractionefficiencyof95%.Livercolloidimaging121PrincipleLivercolloidimaging0.3and1.0microns:arephagocytizedbytheKupffercellsoftheliver.Smallparticles(lessthan0.1micron):distributeprimarilytothebonemarrow.Particleslargerthan1micron:distributemostlytothespleen.whileverylargeparticles:willbedepositedinthelungs.Particlesizeisanimportantdeterminantoftheirdistribution.122AgentsLivercolloidimaging99mTc-sulfurcolloid(SC)

99mTc-Phytate

OrgansDoseLiver，spleen，bonemarrowliver74～296MBq74～185MBq123ImageinterpretationLivercolloidimagingNormalimage----position----size----shape---tracerdistribution124ImageinterpretationLivercolloidi