顱內淋巴瘤影像診斷課件

CASEDISCUSSIONWANGLIJUN2008-7-141Case1:Female,66y2Case1:PLAINMRI3Case1:POST-CONTRASTMRI4Case2:F66Y5Case2:POST-CONTRASTMRI6CASE3:M58Y,NHLwasdiagnosed2.5yearsago,nowfeelheadache(2008-1-25)-C+C72008-1-30892008-5-1510LYMPHOMAPrimarycentralnervoussystemlymphoma(PCNSL)isarareformoflymphaticcancerarisinginthebrain,eye,nerves,spinalfluidsurroundingthebrainandspinalcord,andthecoveringofthebrain,calledduraSecondary:metastasestothenervoussysteminlymphomaaffectingotherorgans11PCNSL:EpidemiologyOncerare(~1%),nowbecomingincreasinglymorecommonIncidencehasrisendramaticallyinpastfewdecades,asPCNSLnowaccountsfor4-7%(16%)ofallnewlydiagnosedprimarybraintumorsIncidencehasrisenintheimmunocompromisedandalsoimmunocompetentpopulation12PCNSL:EpidemiologyImmunocompromisedCongenitalcausesofimmunodeficiency1.Wiskott-Aldrichsyndrome2.IgAdeficiency3.X-linkedlymphoproliferativesyndrome

acquiredcauses1.HIVinfectionandAIDS2.immunosuppressiveregimenafterorgantransplantation13PCNSL:EpidemiologyMedianageofonset55yearsinimmunocompetent,incidenceriseswithageGreatestrisehasoccurredamongtheelderlyMaleismorecommonlyseencomparetofemale(2:1)14DiagnosisHistoryFocalneurologicdeficit(i.e.hemiparesis,aphasia)presentin>50%ofallpatientswithPCNSLAlteredmentalstatus(memoryloss,confusion,etc.)foundin~33%-maybeinsidiousonsetHeadache,nausea(fromincreasedICP)in~33%Maypresentwithnew-onsetseizurein<10%BlurredvisionifocularlymphomaispresentRadiologicimagingHeadCTdetectsmostlesions(~90%)BrainMRImaydetectlesionsmissedonCT15DiagnosisPrimaryCNSlymphomamayarisefromdifferentpartsofthebraindeephemisphericperiventricularwhitematterbeingthemostcommoncorpuscallosum,cerebellum,orbits,andcranialnervesmayalsoharborthetumorHistology:intermediate-tohigh-gradeextranodalnon-Hodgkin'slymphomaofB-cellorigin16RadiologicImaging

TypicalAppearanceinImmunocompetentPatientsUsuallysolitary,non-hemorrhagiclesionindeepwhitematter,nearventriclesLesionisisodensetohyperdense(70%)surroundingvasogenicedemahomogeneouslyenhancingmassSurroundingedemaistypicallylessprofoundthaninmetastaticbrainlesionsorgliomas1764-year-oldwomanwithleft-sidedweakness.AxialunenhancedCTscanshowstypicalhyperdensemass(arrows)inrightparietallobesurroundedbylow-densityzone,consistentwithvasogenicedema.Axialcontrast-enhancedCTscanshowshomogeneousenhancement(arrows)oflesionnearmidline.18RadiologicImaging

TypicalAppearanceinImmunocompetentPatientsintermediate-tolow-signal-intensitytumoronT1-weightedimagesIsointensetohypointensesignalrelativetothegraymatteronT2-weightedimagesAclassicpresentationisthelesionthatcrossesthecorpuscallosuminabutterflypatternEnhancesdenselyandhomogenouslywithgadoliniumcontrastMayalsorevealleptomeningealdiseaseHighsignalonDWI1964-year-oldwomanwithleft-sidedweaknessAxialT2-weightedMRimageshowsheterogeneousmass(blackarrows)ofpredominantlylowsignalintensity.NotecentrallinearT2hyperintensity(arrowhead),likelyrepresentingnecrosis.Alsonotesurroundingvasogenicedema(whitearrows).Axialgadolinium-enhancedT1-weightedMRimageshowsmarkedcontrastenhancementoflesion(arrows).Notemasseffectonadjacentrightlateralventricle.20Post-contrastCoronalT1WtdMRIPost-contrastAxialT1WtdMRIHomogeneouslyenhancingtumorisseeninvolvingthespleniumofthecorpuscallosum(arrows)spreadingacrossthemidline.2172-year-oldimmunocompetentwomanwithprimaryCNSnon-Hodgkin'sB-celllymphomawhopresentedwithprogressivemotorweakness.AxialFLAIRMRimageshowsisointensityoflesionstobrainparenchymaandsurroundingedema.Themassesinvolvedeepwhiteandgraymatter.Axialcontrast-enhancedT1-weightedMRimageshowshomogeneousenhancementofmultiplebilateraltumors.2250-year-oldimmunocompetentmanwithprimaryCNSnon-Hodgkin'sB-celllymphoma.AxialT2-weightedMRimageshowsinfiltrativehyperintensemassexpandinggenuandspleniumofcorpuscallosuminbutterflypattern.contrast-enhancedaxialT1-weightedMRimageshowshomogeneousenhancementoflesion.23頭痛伴口周麻木2個月24RadiologicImaging

AtypicalAppearanceinImmunocompetentPatientsisodensityorevenhypodensityonCTInthesettingofaperiventricularlow-densitylesion,lymphomamayeasilybemisdiagnosedaschronicsmallvesselischemiaorencephalomalaciaDiffuselyinfiltrativelymphomasmaynotexhibitparenchymalenhancementatall2590-year-oldwomanwithnormalimmunestatuswhopresentedwithright-sidedweaknessanddifficultyfindingwords.AxialT2-weightedMRimageshowsill-definedT2hyperintensity(arrows)surroundingleftinternalcapsuleandadjacentlefttemporallobe.Axialgadolinium-enhancedMRimagerevealsbarelydiscernibleparenchymalenhancementincorrespondingregion.Axialcontrast-enhancedCTscanobtained4monthslatershowsmarkedexpansionofleftbasalgangliaandthalamuscausedbyinfiltratingneoplasm,withlossofnormalanatomicboundaries(arrows).2663-year-oldwomanwithprimarymeningeallymphomawhopresentedwithfrequentfallsandvertigo.

AxialFLAIRimageshowshyperintensity(arrow)involvingsulciandleptomeningesofparietotemporalconvexity.Contrast-enhancedT1-weightedaxial(B)andcoronal(C)MRimagesshowfocalthickeningandhomogeneousenhancementofleptomeningesofparietotemporalconvexity(arrows).27Male54y.rightsideweaknesswithheadacheandvomittingfor2months28RadiologicImaging

AtypicalLocationsArareprimarylymphomaofthepinealglandappearssimilartoaprimaryneoplasmofpinealoriginCranialnerves,brainstem,cavernoussinus,ortubercinereummayhavelymphomatousinvolvement29MetastaticCNSLymphomaIn5~9%ofsystemicnon-Hodgkin'slymphoma,secondaryspreadinvolvestheCNS,usuallyintheformofleptomeningealinfiltrates,andhasapoorprognosisParenchymallesions,whenpresent,typicallyresultfromsecondaryinvolvementfromtheleptomeningesviainfiltrationoftheperivascularspaces30Post-contrastAxialT1WtdMRIFigure.Linearenhancementofthecerebellarsulci(yellowarrows)andlefttemporalsulci(redarrow).Diagnosis:SecondaryLymphomawithsubarachnoidtumorseeding(arrows).31Post-contrastCoronalT1WtdMRIDiagnosis:SecondaryLymphomawithcalvarialinvolvement(greenarrow)andassociatedepiduraltumor(yellowarrows)/scalptumor(redarrow)32RadiologicImaging

TypicalAppearanceinHIVPatientsacerebralmassisdetectedinasupratentorialparenchymallocation(55%)withfrequentinvolvementofthecorpuscallosum,basalganglia,andotherdeepcerebralnucleiContrastenhancementisvariable,commonlyofaninhomogeneousorbizarrepattern.Solitaryringlikeenhancementismorelikelyseeninthisgroupnecrosisdevelopsinthetumor(64%)Multiplelesionsmaybeseen(50%)Periventricularlesionsfrequentlyinvadetheventricularsurface,causingependymalseeding(38%)However,meningealenhancementissurprisinglynotfrequent.3338-year-oldmanwithHIVwhopresentedwithdisorientationandconfusion.Axialgadolinium-enhancedT1-weightedMRimageshowssolitaryringlikeenhancementofmassandperipherallow-signal-intensityhalo(arrows).3435-year-oldmanwithHIVwhopresentedwithlowerextremityweakness.Noteatypicallymphomapresentedasnonenhancinglow-densitylesioninrightbasalgangliaonCT,initiallythoughttobealacunarinfarct.Axialprotondensity-weightedMRimageobtained3monthsafterAshowshyperintenselesion(arrows)withirregularbordersatsamelocation.Coronalgadolinium-enhancedT1-weightedMRimagerevealsintervalgrowthandenhancementofpallidalmass(arrows).Subtleenhancement(arrowhead)isalsoseeninependymalsurface.