醫(yī)學(xué)影像學(xué)課件：Diagnositic Radiology Skull and Brain

DiagnositicRadiology

SkullandBrainContentsExaminationmethodsandnormalfindingsofbrainCTandMRfindingsofcommondiseasesofbrain:-Skullfracture-Acuteepidural,Acutesubduralhematoma,IntercerebralHematoma,Ventricular/subarachnoidhemorrhage-BrainInfarct-Braintumor(Astrocytoma,Meningioma,Cerebralmetastases)ObjectiveAndRequestsFamiliarityoftheexaminationmethodsandnormalCTfindingsofbrainHoldCTorMRfindingsofcommondiseasesofbrain:-Skullfracture-Acuteepidural,Acutesubduralhematoma,IntercerebralHematoma,Ventricular/subarachnoidhemorrhage-BrainInfarct-Braintumor(Astrocytoma,Meningioma,Cerebralmetastases)MethodsofExaminationPlainfilmofskull:Tocheckfractureandotherdiseaseofskull.DigitalsubtractedAngiography(DSA):TostudycerebralvasculardiseasesanddointerventionaltherapyCT:Toestimatetrauma,cerebralhemorrhage,calcificationandvasculardiseasesMRI:ItisgoodforrevealingthediseasesofCNS;MRAisanon-traumaticmethod,canconfirmcerebralvasculardiseasesPlainfilmThismethodisverysimpleandcheapSomelesionscanbefoundbyitSkullmetastasis

tumor

(breastcancer)

DSA

(digitalsubtractionangiography)carotidarteriography

Vertebralarteriography

Toshowthevasculardiseasessuchasaneurysm,arteriovenousmalformation,bloodsupplyofneoplasmDointerventionaltherapyArterialvenousmalformation(AVM)subarachnoidhemorrhage

anteriorcommunicatinganeurysms

HeadCTBaselineistheorbitomeatalline,Scanisstartedfromthelinetotop,thicknessis10mm.Contrastscancanmakediseaserevealedwell,andisgoodfordifferentdiagnosis.BaselineHeadCTTodisplayinfarct,tumors,hemorrhage,infections,abnormality.CTAinternalcarotid

arteryocclusionatherosclerosissubarachnoidhemorrhage

aneurysms

CTCTACBFCBVTTPTherighttemporallobe

infarctionCBF,

CBVdecreasedandTTPincreasedCTperfusionHeadMRScanprotocol

routinebrain-SagittalT1SE-AxialT2FSE-AxialFLAIR-Axial(coronal)T1FSPGR-CoronalssfseT2

AxialFSET2TR/TE4367/102,32ETMatrix256x192(512Z)30slices/2passes5mm/0mm2:21,2nex21FOV,32kHzHeadMRAxialFLAIR-TR/TE/TI8800/124/2200-Matrix256x160(512Z)-5mm/0mm-3:32,1nex-21FOV,16kHzAxial(coronal)FSPGRT1MinTR/TE/40FAMatrix512x192(160)2.5mm/0mm2:40(2:15),1nex21FOVx.7512.5kHzHeadMRIGraydegreeofnormaltissueonT1,T2WIT1WIT2WI

WhiteMatterwhitegraygrayGrayMattergraywhitegrayC.S.FblackwhiteFatwhitewhitegrayCorticalblackblackMarrowwhitegrayMeningesblackblack

HeadMRIMRAMRVT2WIDifusionperfusionPerfusion—3DASL(arterialspinlabeling)

ASL：CBFDiffusiontensorimaging(DTI)S.Mori,B.Stieltjes,R.Xue,M.Solaiyappan,W.Kaufmann&P.vanZijl,F.M.Kirbyresearchcenter,JohnsHopkinsUniversity,Baltimore.SusceptibilityWeightedImaging(SWI)SWIMultiplecavernoushemangiomaT1WICTFingertappingFunctionalmagnetic

resonanceimaging

(fMRI)MRspectroscopy

（MRS）braintumor

spectrumNAA（2.0ppm）decreasedCho(3.2ppm)increasedLac(1.32ppm)increasedNormalaxialCTofbrainThesliceat2cmabovethebaseline:-Fourthventricle-ponsNormalaxialCTofbrainThesliceat3cmabovethebaseline:-Suprasellarcistern-Ambientcistern-FourthventricleNormalaxialCTofbrainThesliceat4cmabovethebaseline:-Thirdventricle-QuadrigeminalcisternNormalaxialCTofbrainThesliceat5cmabovethebaseline:-Anteriorhornoflateralventricle-Thirdventricle-Trigonareaoflateralventricle-Superiorcerebellarcistern-LateralfissurecisternNormalaxialCTofbrainThesliceat5cmabovethebaseline:-Headofcaudatenucleus-Lentiformnucleus-Internalcapsule-ThalamusNormalaxialCTofbrainThesliceat6cmabovethebaseline:-BodyoflateralventricleIntracranialphysiologiccalcificationPhysiologiccalcificationscommonlyarisefrom:-Caudatenucleus-Lentiformnucleus-pinealbody-Habenularcommissure-Falxcerebri-Choroidplexus-DentatenucleusPhysiologiccalcificationCaudatenucleus,calcificationPhysiologiccalcificationLentiformnucleus,calcificationPhysiologiccalcificationPinealbody,calcificationPhysiologiccalcificationFalxcerebri,calcificationPhysiologiccalcificationChoroidplexus,calcificationPhysiologiccalcificationDentatenucleus,calcificationCTFindingsofHeadTraumaTypesofskullfracture:-Linearfracture:itisvisualizedasasharp,darktranslucentline,oftenirregular,andoccasionallyofbranchingcharacter.-Depressedfracture:oneormorefragmentofbonemaybeseparatedanddepressedintothecranialcavity,andwithmultiplefracturelines.-Basalskullfracture:thisisasevereconditionoftrauma.HeadTraumaLinearfracture-CTshowsasharp,darktranslucentlineofoccipital

bone.HeadTraumaDepressedfracture-CTshowsmultiplefragmentofleftfrontalboneanddepressedintothecranialcavity,withasubduralhematoma,andalittleairaccumulation.HeadTraumaAcuteepiduralhematomas-resultfromtheinjuryofmeningealvessels.Thebloodaccumulatesbetweentheinnertableandtheduramater,whichalwayshappenswiththeacuteheadtrauma.-CTfindings:Thereisafusiformorbiconvexhighdensityshadowundertheinnertable,oftenwithskullfractureandoccupyingeffect.HeadTraumaAcuteepiduralhematoma-Afusiformdenseshadowclosedtherightfronto-parietalinnertable,withthegreymatteriscompressedandthefalxcerebrislightlyshifttothenormalside.Thedepressedfractureoftherightfrontalboneisalsoidentified.HeadTraumaAcutesubduralhematoma-resultsfromhemorrhageintothepotentialspacebetweentheduraandarachnoidmembrane.Itisduetotheinjuryoftheveinsorvenoussinus.Traumaisconsideredtobethecauseofthiscondition.-CTshowsameniscusorband-likedhighdensityshadowbeneaththeinnertable,withoccupyingeffect.HeadTraumaAcutesubduralhematoma-Thereisaband-likeddenseshadowclosedtotheleftfronto-parietalinnertable,withleftventricleandmidlinestructureshifttotherightside.AcutesubduralhematomaSubacutesubduralhematoma(isodense)SubacutesubduralhematomaonMRIHeadTraumaCerebraledema:mayproducedbytrauma-Waterhasalowerdensitythannormalbraintissueandthereforedecreasesthedensityofthebraintissueitoccupies.-CTappearsaspatch-likedlowerdensityshadow.Theedemacouldbelocalizedorfocal,largerareaofedemacanproducemidlineshift.Thebilateralandmorediffuseedemacanmaketheventriclesextremelysmall,cerebralcisternsinvisible.HeadTraumaCerebralcontusion-Includingtraumaticfocaledema,andhemorrhageinbrain(Hematoma).-CTshowspatchoflowdensityarea,andpresenceofspot-likedhighdensityshadow.Thelargerlesioncanbeassociatedwithoccupyingeffect.CerebralcontusionHeadTraumaIntercerebralhematoma-Itisproducedbyheadtrauma.Hematomascouldbesubcortical,deep,orintraventricular.-Intheseveretrauma,CTscanningusuallydemonstratedmultiplefindings,suchassevereedema,epidural,subdural,intracranialhematoma,andmarkedventricularcompression.HeadTraumaIntercerebralhematoma-CTfindings:CTexhibitsaround,ovalorirregularhighdensityshadow,andwiththelowerdensityedemasurroundingthehematomaandocuppyingfeatures.HeadTraumaIntercerebralhematoma-Thereisahighdensityparenchymalhematomaintherightfrontallobe,withairregularityinshape,andalowerdensityedemasurroundingthehematoma.Theirregularsubduralhematomaisalsoseen.Thefalxiscompressedanddisplacedtotheleft.IntercerebralhematomaHeadTraumaVentricular,subarachnoidhemorrhageCTfindings-ventricularhemorrhage:thereispatchdenseshadowinventricle;bleedingcouldfillwithventricleandappearsaventricularshape.-subarachnoidhemorrhage:thecerebralsulcus,fissureandcisternappearashighdensity;ordisplaysacisternshapeifbloodismore.VentricularhemorrhageHeadTraumaSubarachnoidhemorrhage-CTshowsthesulcusofbilateralfronto-parietallobeandlongitudinalfissurearehighdensity.subarachnoidhemorrhageCerebralvasculardiseasesIntracerebralhemorrhage-cause:hypertension,aneurysm,vascularmalformation;Hemorrhageisduetosmallvesseloraneurysmruptured.Bleedingproduceshematomas.-site:basalganglia,thalamusarethemostcommonhemorrhagicsites.Hematomamayruptureintoventricleandsubarachnoidspace.-staging:acute,subacute,chronic,absorptionandcysticchanges.IntracerebralhemorrhageAcutehemorrhage(oneweek)-CTrevealsaintracerebral,homogeneousandwell-definedhighdensityhematoma,alwayswithedemasurroundingit,andmasseffects.Thehematomainthethalamusshowsabean-shaped(kidney-liked)shadow.Ifahematomarupturedintoventriclesorsubarachnoidspace,therearehighdensityshadowwithinventriclesandsubarachnoidspace.TherightthalamushematomarupturedintoventriclesTwodaysTwoweeksAftertwoweeksOnedayBrainInfarctArterialobstructionproducescerebraltissuesischemicinfarct.Cerebralarteriosclerosisisoneofthemostcommoncausesofinfarct,seeninthepatientswithhypertension.BrainInfarctonCTAlowdensityshadowinvolvinggreyandwhitematterintherighttemplelobe,nooccupyingeffect.Andasmallinfarctinthethalamusontheleftisalsoidentified.AftertwodaysA69year-oldmanwhosufferedfromleftlimbweaknessfor4hours8dayslaterA83year-oldwomanwhosufferedfromrightlimbweaknessandaphasiafor6hoursAmale,56yearsold,sufferedfromleftextremityof

movementandsensory

disturbanceforhalfanmonth.Leftlimbs

activityobstacle

for8weeks

BrainInfarctonMRILefttemplelobeinfarct-T2,FLAIRhighsignal-T1lowersignal

Lacunarinfarct

Alacunarinfarctisproducedbyocclusionofasmallendartery,about10~15mmdiameters.Theselesionshaveapredilectionforthebasalganglia,internalcapsule,pons,orcoronaradiata.Comparativeimaging

–infarctAcute

brain

infarction（＜6hr）

DW