脑梗死的血管定位PPT课件.ppt

脑梗死的血管定位,.,内容,脑供血动脉解剖脑梗死的血管定位,人脑动脉解剖,.,脑动脉两大体系,颈内动脉系：大脑前部部分间脑椎基底动脉系：大脑后部部分间脑脑干小脑,小脑幕为界,顶枕沟为界（3/2),脑动脉供血系统模式图,脑的主要供血动脉。(A)脑腹侧观。方块区域放大图显示Willis动脉环。(B)脑外侧面观和(C)中间矢状面显示大脑中/前/后动脉。(D)冠状切面显示大脑中动脉行程。,颈内动脉系统,MCAACA脉络丛前动脉,.,大脑中动脉（MCA）供血范围,MCA,ACA,PCA,MCA皮质支供应：半球外侧面（额中回以下、中央前后回下3/4、顶下小叶、枕叶月状沟或枕外侧沟以前、颞下回上缘或上半以上的部分）；岛叶；颞极内外侧；额叶眶面一部分。,MCA中央支供应：壳核、尾状核、内囊前肢、内囊膝的背外侧和内囊后肢的背部区域。立体看，供应内囊上3/5,大脑中动脉（MCA）供血范围,大脑前动脉（ACA）血液供应,ACA皮质支供应：半球内侧面为顶枕裂以前皮质和胼胝体；在背外侧面达额中回上缘或上半、额上回、中央前后回上1/4、顶上小叶及眶部内侧半等区域。,ACA中央支供应：部分额叶眶面皮质、外囊、尾状核和豆状核前部、内囊前肢和内囊膝部和后肢前边部分。,脉络丛前动脉：侧脑室下角的脉络丛，并供应外侧膝状体、内囊后肢的后下部、大脑脚底的中1/3、苍白球等，易形成血栓阻塞。,脉络膜前动脉的供血范围,左图详示：基底节区的血液供应。,脉络膜前动脉,脉络膜前动脉，14支，以3支最多，为一组较细小而恒定的血管，在后交通动脉起始远侧2mm处由颈内动脉脉直接发出。该动脉在未穿入侧脑室下脚之前，除发13个皮质支外，还发出23个穿支，1支穿视神经内侧至大脑脚，另两支即为纹状体内囊动脉。此动脉主要营养尾状核尾，行程长，管径较小，易发生栓塞。,D.AxialT2-weightedimage(2500/80)revealsthepresenceofaninhomogeneousmassintherightlateralventricle.Thelowsignalintensitysuggetsthepresenceofcalcificationandhemorrhage.E.Angiogramoftherightinternalcarotidarteryobtainedonday3demonstratesahypervascularmassfedfromtherightanteriorchoroidalartery(arrows).,WhichoneistheAnteriorChoroidalArtery?,脉络膜前动脉闭塞常引起三偏症状群，特点为偏身感觉障碍重于偏瘫，而对侧同向偏盲又重于偏身感觉障碍，有的尚有感觉过度、丘脑手、患肢水肿等。,内囊额状断面脑后片图显示各部位血液供应来源。,中央前回及中央后回的血液供应图,椎基底动脉系统,VABA,.,椎动脉（VA）V1（骨外）段：向上进C6横突孔。V2（椎间孔段V3（脊椎外）段：V4（硬膜内段）：过枕骨大孔，在脑桥及延髓交界处合成基底动脉。近侧椎动脉段解剖（A侧位；B前后位；C颏顶位）：骨外段（V1）横突孔段（V2）椎外段（V3）4.硬膜内段（V4）5.枕骨髁的大概位置,椎动脉行程,图A：斜侧位观；图B：前后位观；图C：俯观。,1.左椎动脉2.脑膜后动脉3.小脑后下动脉（PICA）4.基底动脉5.小脑前下动脉(AICA)6.脑桥外侧支7.小脑上动脉（SCA）8.大脑后动脉9.小脑半球支大水平裂10.SCA的小脑半球分支11.小脑蚓上动脉,椎基底动脉系统及其分支解剖（侧位）：,椎基底动脉系统及其分支解剖（正位）：,1.右椎动脉2.左椎动脉3.脊髓前动脉4.小脑后下动脉（PICA）5.基底动脉6.小脑前下动脉（AICA）7.脑桥外侧支8.小脑上动脉（SCA）9.大脑后动脉10.后交通动脉11.颈内动脉,大脑后动脉（PCA）血液供应,中央支：丘脑、下丘脑、底丘脑、膝状体以及大部分中脑。此外，分支到侧脑室及第三脑室脉络丛。,变异大。主要来自PCA（72.5-88.3%）；来自ICA（6.8-20.2%）；两部分平均参加（4.3-11%）。,PCA供血区模式图,皮质支：半球底面和内侧面一部分（包括：海马回、梭状回、颞下回、舌回、窟窿回峡、楔叶、楔前叶后1/3及顶上小叶后部）,Bloodsupplyofthethreesubdivisionsofthebrainstem.Diagramofmajorsupply.Sectionsthroughdifferentlevelsofthebrainstemindicatingtheterritorysuppliedbyeachofthemajorbrainstemarteries.,脑桥的血液供应特点,桥脑的血供源自椎基底动脉，桥脑基底外侧和被盖部由短旋动脉供应；桥脑基底部内侧由基底动脉中央支供应，旁正中支供应桥脑被盖部正中部分脑室底部、外展神经核、内侧纵束和网状结构；桥脑基底部和被盖部最外侧为长旋动脉供应。由于外侧区侧支循环丰富，发生梗塞概率较低。而桥脑旁正中动脉、短旋动脉呈直角起自基底动脉，易受高血压的影响而出现动脉粥样硬化，易出现梗塞。,脑桥梗死的临床特点,貌似大脑半球病变的纯运动性偏瘫占桥脑梗塞的60.9%。这是因为锥体束位于桥脑基底部，基底部由基底动脉的旁正中深穿支供应血流，该部位动脉易有动脉硬化性改变和透明变性，其近端闭塞时导致基底部正中梗塞，使未交叉的锥体束受损。PICA和SCA引起的梗塞通常仅累及小脑；而AICA（供应脑桥外侧被盖部和小脑中脚）不同，它引起的梗塞灶多累及脑干和小脑中脚。,桥脑梗塞时交叉性瘫及颅神经麻痹并不常见，因桥脑的颅神经核多分部于被盖部，由较丰富的长旋动脉及小脑上动脉供应血流，后交通动脉、大脑后动脉和小脑上动脉有侧枝循环，所以颅神经可不受影响。,脑桥梗死的临床特点,脑桥上/中部旁中线综合征,由基底动脉旁中央支血供障碍引起；病变对侧中枢性舌瘫对侧中枢性上下肢瘫痪同侧小脑性共济失调,Patientswithunilateralparamedianinfarctionstypicallypresentedapuremotorhemiparesisthatprogressedoverthefirst3daysandwasaccompaniedbydysarthriaandhomolateralataxia.,桥脑上外侧综合征,小脑上动脉闭塞引起；眩晕、恶心、呕吐、眼球震颤（前庭核损害）两眼向病灶侧水平凝视不能（脑桥侧视中枢损害）同侧肢体共济失调（脑桥臂、结合臂、小脑齿状核损害）；同侧Horner综合征（下行交感神经损害）同侧面部感觉障碍（三叉神经感觉束损害）和对侧痛觉、温度觉障碍（脊髓丘脑束损害）；对侧下肢深感觉障碍（内侧丘系外侧部分损害）双侧听力障碍，对侧较重。,少见SCA综合征出现病变对侧感音性耳聋,脑桥腹下部综合征（Millard-GublerSyndrome),同侧外展N麻痹同侧周围性面瘫对侧中枢性舌瘫一；对侧肢体瘫。也其它位置不同的突出症状可能出现小脑前下动脉阻塞引起。,脑桥基底内侧综合征（FovilleSyndrome),病灶侧周围性面瘫；两眼向病灶侧同向注视麻痹；病灶对侧偏瘫；基底动脉旁正中支闭塞引起。,小脑后下动脉综合征（Wallenbergsyndrome),现证实10由PICA引起，75由一侧椎动脉闭塞引起。余下由基底动脉闭塞引起。,延髓内侧综合征（Dejerine综合征）,椎动脉及其分支或基底动脉后部血管阻塞，引起延髓锥体发生梗死时产生同侧舌肌麻痹（XII脑神经损害）和萎缩，对侧上下肢中枢性瘫痪以及触觉、位置觉、振动觉减退或丧失。,Magneticresonanceimageofthefluidattenuatedinversionrecoverysequencefortheaxial(left)andT2weightedcoronal(right)sections.Thereisawelldemarcatedunilateralmedialmedullaryinfarctjustbelowthepontomedullaryjunction.Therightsideofeachimagecorrespondstotheleftsideofthebrain.,大脑动脉血管供血分区CT解剖(图文),脑的供血模式图,左枕叶梗死。（PCA终末支）,Figure1:(a)NormalinitialCTofthepatient;(b)ThecranialCTtwodaysaftertheincidentshowssignalchangesconsistentwithsimultaneousinfarctsintherightMCAandPCAareas;(c)InthedigitalsubtractionangiographyoftherightICA,PCAisseentooriginatefromtherightICAthroughPCoAi.e.fetaltypePCA,PICAOntheleftCT-imagesofaleft-sidedPICA-infarction.Noticetheposteriorextention.Theinfarctionwastheresultofadissection(bluearrow).,OntheleftCT-imagesofaleft-sidedPICA-infarction.Inunilateralinfarctsthereisalwaysasharpdelineationinthemidlinebecausethesuperiorvermianbranchesdonotcrossthemidline,buthaveasagittalcourse.Thissharpdelineationmaynotbeevidentuntilthelatephaseofinfarction.Intheearlyphase,edemamaycrossthemidlineandcreatediagnosticdifficulties.Infarctionsatpontinelevelareusuallyparamedianandsharplydefinedbecausethebranchesofthebasilarareryhaveasagittalcourseanddonotcrossthemidline.Bilateralinfarctsarerarelyobservedbecausethesepatientsdonotsurvivelongenoughtobestudied,butsometimessmallbilateralinfarctscanbeseen.,SCAOntheleftCT-imagesofacerebellarinfarctionintheregionofthesuperiorcerebellararteryandalsointhebrainstemintheterritoryofthePCA.Noticethelimitationtothemidline.,ACA：A1segment:fromorigintoanteriorcommunicatingarteryandgivesrisetomediallenticulostriatearteries(inferiorpartsoftheheadofthecaudateandtheanteriorlimboftheinternalcapsule).A2segment:fromanteriorcommunicatingarterytobifurcationofpericallosalandcallosomarginalarteries.A3segment:majorbranches(medialportionsoffrontallobes,superiormedialpartofparietallobes,anteriorpartofthecorpuscallosum).,AnteriorchoroidalarteryTheterritoryoftheanteriorchoroidalarteryencompassespartofthehippocampus,theposteriorlimboftheinternalcapsuleandextendsupwardstoanarealateraltotheposteriorpartofthecellamedia.ThewholeareaisrarelyinvolvedinAChAinfarcts.Ontheleftanuncommoninfarctioninthehippocampalregion.PartoftheterritoryoftheanteriorchoroidalarteryandthePCAareinvolved.,MiddlecerebralarteryTheMCAhascorticalbranchesanddeeppenetratingbranches,whicharecalledthelaterallenticulo-striatearteries.Theterritoryofthelaterallenticulo-striateperforatingarteriesoftheMCAisindicatedwithadifferentcolorfromtherestoftheterritoryoftheMCAbecauseitisawell-definedareasuppliedbypenetratingbranches,whichmaybeinvolvedorsparedininfarctsseparatelyfromthemaincorticalterritoryoftheMCA.OntheleftaT2W-imageofapatientwithaninfarctionintheterritoryofthemiddlecerebralartery(MCA).Noticethatthelaterallenticulo-striateperforatingarteriesoftheMCAarealsoinvolved(orangearrow).,OntheleftimagesofahemorrhagicinfarctionintheareaofthedeepperforatinglenticulostriatebranchesoftheMCA.,OntheleftenhancedCT-imagesofapatientwithaninfarctionintheterritoryofthemiddlecerebralartery(MCA).Thereisextensivegyralenhancement(luxuryperfusion).Sometimesthisluxuryperfusionmayleadtoconfusionwithtumoralenhancement.,Posteriorcerebralartery(PCA)DeeporproximalPCAstrokescauseischemiainthethalamusand/ormidbrain,aswellasinthecortex.SuperficialordistalPCAinfarctionsinvolveonlycorticalstructures(4).Ontheleftapatientwithacutevisionlossintherighthalfofthevisualfield.TheCTdemonstratesaninfarctioninthecontralateralvisualcortex,i.eleftoccipitallobe.,Therearetwopatternsofborderzoneinfarcts:1.CorticalborderzoneinfarctionsInfarctionsofthecortexandadjacentsubcorticalwhitematterlocatedattheborderzoneofACA/MCAandMCA/PCA2.InternalborderzoneinfarctionsInfarctionsofthedeepwhitematterofthecentrumsemiovaleandcoronaradiataattheborderzonebetweenlenticulostriateperforatorsandthedeeppenetratingcorticalbranchesoftheMCAorattheborderzoneofdeepwhitematterbranchesoftheMCAandtheACA.,OntheleftthreeconsecutiveCT-imagesofapatientwithanocclusionoftherightinternalcarotidartery.Thehypoperfusionintherighthemisphereresultedinmultipleinternalborderzoneinfarctions.Thispatternofdeepwatershedinfarctionisquitecommonandshouldurgeyoutoexaminethecarotids.,Ontheleftimagesofapatientwhohassmallinfarctionsintherighthemisphereinthedeepborderzone(bluearrowheads)andalsointhecorticalborderzonebetweentheMCA-andPCA-territory(yellowarrows).Thereisabnormalsignalintherightcarotid(redarrow)asaresultofocclusion.Inpatientswithabnormalitiesthatmayindicateborderzoneinfarcts,alwaysstudytheimagesofthecarotidarterytolookforabnormalsignal.,OntheleftanotherexampleofsmallinfarctionsinthedeepborderzoneandinthecorticalborderzonebetweentheMCA-andPCA-territoryinthelefthemisphere.,OntheleftanexampleofinfarctionsinthedeepborderzoneandinthecorticalborderzonebetweentheACA-andMCA-territory.Theabnormalsignalintensityintherightcarotidistheresultofanocclusion.Thiscombinationoffindingsissocommon,thatonceyouknowthepattern,youwillseeitmanytimes.,脉络膜前动脉供血区梗死,A9-year-oldpreviouslyhealthygirlwasadmittedtotheEmergencyRoomwithaneight-hourhistoryofsuddenonsetofsevereheadache.Thepainwaspulsatileandbilateralandnotaccompaniedbyothersymptoms.Thereisnohistoryofmigraine,epilepsyorstroke.Parentsreportedthatsoonaftertheonsetoftheheadachethepatientbecamedrowsyforaboutonehour.Notriggerfactorwasidentified.Ontheneurologicalexamination,thepatientwasalertandwellorientedwithnootherabnormalitiesbutmildnuchalrigidity.Computedtomographyofthebrainrevealedhemorrhageintherightlateralventricle(Fig1)andgadolinium-enhancedmagneticresonanceimagingstudyofthebraindisclosedaheterogeneouslesioninthemesialportionoftherighttemporallobe,aboveandinsidethetemporalhornofthelateralventricle.Thelesionextendeduntilthesubependimaryareaofthetrigonooftherightventricle.ThelesionwashypointenseonT1andT2-weightedimagesandenhancedwiththecontrast.OtherhyperintenseT1andT2-weightedimageslesionswereseenintherightlateralventriclesuggestingbleeding.Magneticresonanceangiographyandcerebralangiographydisclosedanarteriovenousmalformationinpartofthechoroidplexus,suppliedbytheanteriorchoroidalartery(Figs2and3).TheAVMwasclassifiedaccordingtoSpetzlergradingsystemasgrade3(deepvenousdrainage:1;eloquencearea:0andsize:2).,Lacunesmaybeconfusedwithotheremptyspaces,suchasenlargedperivascularVirchow-Robinspaces(VRS).TheVRSareextensionsofthesubarachnoidspacethataccompanyvesselsenteringthebrainparenchyma.WideningofVRSoftenfirstoccursaroundpenetratingarteriesinthesubstantiaperforataandcanbeseenontransverseMRIslicesaroundtheanteriorcommisure,eveninyoungsubjects(5).OntheleftCT-andMR-imagesattheleveloftheanteriorcommisure(bluearrows).OntheCTthereisahypodenseareaintherighthemisphere,whi