颈部动脉夹层的影像诊断与鉴别诊断.docx
颈部动脉夹层的影像诊断COMPANY概述02影像诊断04治疗03）鉴别概述颈动脉：双侧颈总动脉在C4水平分叉为颈内动脉、颈外动脉。颈总动脉分叉处是动脉斑块形成、动脉狭窄最好发的部位。椎动脉：锁骨下动脉的第一分支。从C7横突的前面向上,进入C6横突孔垂直上行，出CI横突孔后，走行至枕骨大孔入颅。颈内动脉主要分支：大脑前、中动脉，后交通动脉，眼动脉，脉络丛前动脉。颈内动脉主干分为：颈段(CI),岩段(C2),破裂孔段(C3),海绵窦段(C4),床突段(C5),眼段(C6),交通段(C7)颈内动脉主要分支：大脑i前、中动脉，脉络丛前动脉，后交通动脉及眼动脉。颈内动脉主干分为：颈段(CI),岩段(C2),破裂孔段(C3),海绵窦段(C4),床段(C5),眼段(C6),交通段(C7)二、椎动脉(VertebralArteryJVA)V3（脊椎外）段：C2枕骨大孔下方/硬脑膜。V4（硬膜内段）：过枕骨大孔，在脑桥及延1»交界处合成基底动脉O二、颈部动脉夹层 颈部动脉夹层(CerViCalarterydissection,CAD)是指颈部动脉内膜撕裂导致血液流入其管壁内形成壁内血肿，继而引起动脉狭窄、闭塞或动脉瘤样改变。 好发于血管分叉处及活动度大、易受挤压的部位(如：颅外段颈动脉Cl段及椎动脉的V2、V3、V4段等) 主要为颈内动脉夹层(internalCarOtidarterydissection,ICAD)禾口椎动脉夹层(Vertebralarterydissection,VAD) 在所有脑血管意外中占2%,年龄小于45岁的患者卒中的重要病因(20%)。病因.根据诱发原因的不同，CAD可分为创伤性或自发性CAD。.自发性夹层患者可能存在潜在的动脉壁结构缺陷，如动脉粥样硬化、纤维肌肉发育不良、血管退行性改变、感染、自身免疫性疾病和遗传性结缔组织病有关。.颈部过度伸展或旋转，颅外血管受到机械拉伸而损伤。咳嗽、撮鼻涕、颈部按摩、从事某些体育活动如举重、羽毛球、高尔夫球、网球及瑜伽等都可能导致CAD。.中层滋养血管破裂或内膜撕裂，血液流入管壁内，导致血肿形成。内膜撕裂处继发血栓形成，血栓脱落引起远端动脉栓塞。.夹层在内膜和中膜之间，壁内血肿可能会使动脉壁扩张压迫正常管腔直径，导致管腔狭窄或闭塞引起缺血症状或由于血流动力学功能不全导致卒中。.夹层在中膜和外膜之间，则可能导致动脉瘤样突出，压迫相邻颈部神经或颈交感干导致颈痛及霍纳综合征。四、临床表现ICAD临床表现多样,可表现为单侧头痛（额部，眶周）或颈部疼痛,可伴有不全HOmer,s综合征（眼睑下垂和瞳孔缩小,眼球轻度内陷，但不出现面部无汗症状，50%）o数小时或数天后，继发脑血管病可导致严重神经功能缺损，缺血性卒中是CAD患者最常见的脑血管病变类型，常见于大脑中动脉供血区域。VAD可表现为颈后疼痛或枕下头痛，继而后循环缺血。短暂性缺血症状较少见，脑卒中累及脑干、小脑、丘脑或枕叶最为典型。五、影像表现DSA常见表现：L不规则或节段性狭窄；2.锥形闭塞；3.不规则的梭形或瘤样扩张，伴或不伴远端狭窄；4.假腔形成；5.双腔征。五、影像表现CTA表现为动脉偏心性狭窄伴外管径扩张、串珠征或节段性狭窄、壁内血肿、双腔征、内膜瓣，血流进入内膜和外膜之间的层面可形成动脉瘤样扩张（假性动脉瘤）O高分辨率MR显示血管狭窄、闭塞或管径不规则；内膜瓣、假性动脉瘤和壁内血肿。由于撕裂的动脉壁内膜将血管分为真、假两腔，真腔常呈偏心性狭窄，多为类圆形，是没有完全闭塞的血管腔；假腔较宽，其特征为新月形高信号区域，为内膜分离伴血肿形成所致。Fig.8:CTAofIheneckdisplayaflap(wNtearrow)intcngt>tVAFig.4:NECTpdormd2dyBShertheonsetOfsymptomsshowthhypwdEanxJrahematoma(whilearrows).F3.5:CTAo(theHghlICAshowingIUmC(Ina11gmg(wAearrow),andmtramuraihematoma(blackarrow)ThewholevesselBize(lumenwal)braised(bar)FlG 1. DWI (A) md FS W () 6CW ahypMgai Gfa mural hmtom a nt carotid Irtery csccto MR anpo7a- Phy Q thow tH MiXeqMmr nMrorduuo <rwx>vs of artfulFIG1DWlin3drffbctPariemSwithcervicalinternalcardartyCfaKCt)CmCneKentshapedhyperyjalofwaMhematomas(A<sodrrors.nnhapedhynu9ulofawallh<bmatcmaS,Sdfderrowflinearhyperitenstyofpharyngeallymphoidbssue(AandB.arrow-heck).andnoduhrhyperu9mIofaga11do八|&dkhFdrrowfFKHyperacutedHsect>orwithawalKefmtomippcanr<hyperwtemeOCDWlA.arrowwithapparent4fTuonco*ffr*nrrestncto(8.CFFoWnotvsleonFSTlWIICdotfMOrn)W)ortheMid>ourccknacoft<ne-cf-ftMRangtography(D.dottedMowjPFr6.PatientwithanIntefnOICaroUdandVEebrMCAD.MRIwithTlWOghlmwithuppmskM)ofIbeCMandclrcuUtm(bloodin*xal(AC)andUgittMslkreconstruction!(d),CADwitha2ommhypnnt*ns<inT1,affctmthSUtAptrousandcavmouPOfUOmtheleftinternaACMoUdartery(a.candd.arrowandportionYJo(IhertvertebralarteryQfToW).Fig.2.AxialT1-wighvtdMRlwithcontractnru9o*theh*dandnck<Ag.3.MRAMtheheadandneck60Wlnqnqhtcarotidarterynarrowing(arrow)COrHlmmwitharightOKotidarteryd½cctk>inaptcntwithWMHorncfsyndrome.IsoldtcdHomersyndromeshowingtheCaQntrk"crescentwg11(rrow)ofthefight3c0bdarterycon-ntwhhacarotid11*rydmect>onFig.14:DoubleCaroMdasecSonThisisthefirstFLARImageinaCefebTMWstudyrfor11Mjinapatientw<haAutptttonoffttrnkFLAJRknapdarydpctsthhycntcnem&amuralbcm4iomeandtheSCCefWiCHowVOKIIhotrepresentlumenStenoaJS(whitsarrowB)HgIftMrv*miurwMaswrnor*b*h11b<v¾>mkmtr»ct)aMVlfWblflWIH>7aftwtwiMp<krCr.jkDiIIUNnnu>ly,d*g*<rta*ty(T3mrwtrap*M«emwnmMzrrMFur1.Inagmg*mdrmd*ctonLumennrfcnanaInranljralhrwors(IMHlT.r)MurcMshownmMBofWtPftl11w11mi-Wd*coonUMnga2WcMgnaithiMnoicoverEUc.mtgnctza8rvwedrapidgu0R"dstecaXchoIMPRAGEIdemont:raMTl*hypmnrr*rM1IntrIwlMfiraIkv11ji<30tivtermfCA*)v>IhefWtnHyjrfAarwmXWbmK1，TlMMaturationES)#iowedTl-hypenmaeMlongtiebterarfCAsandbothVtnrbrdarterywattsJB：avows).ThecSd*cnlsqrniabnrmtaicngIteve<ebralOriEryonTIFSWMla*ctolackUaupewMnmPertYMCUurvnoutPMKueanOmwme5«MrronMPRAOEMMmUrMrtenrproctonmQM"H0rrwbmntnk9.mdudr9mu0VWSOOMe2;arowMat.RightICAtc<tMlOO>fo,.l>6<ac6ICA,11osis>100<53-0.T>S.5-4I7DThBaer4hadaleICAPSeUdaareUryvnwtdsst9ntap(Oanew'Flg.:CTAofdoublevesseldssecDon(rgttVAandIeftICA)Notertwnur.hematoma(wfrow)andrwrowsgoftbannalIunwn(btecWrOWv)g1>:AaTlLUP9tV*TMg9l*WBCRWIlMHHrtBTW11WJf»*md<im4wmaOEM：，MIhelzvowIMmrCctmnmiSTVMr*m4qa>Mtcsate(MaelrvomJR 哇、-g Mww Laswf s> 5 1: f as wtel 9。F%10?9» N ?M tii R OSAC 4s. sm Hr* *tLn t5z * L*M.a*l.qaMM RM < A ftr An S hsrf*u Lslrz ewtc « W9 isc .Ms0 2£3scwfe £ S SeiFOF Vr .st tf ££ rvae« 9i ltfi* «> Ss" A £Fig.22：CTAOfIheVoHCtXdves9ebshowkinkingoftheletVA.TinsftndngHapanddoubtelumen(biackarrow)Thejmof*dncntSlICflHIhlp._dlssecl>o(5ecg23).Fig.23:SamepatientasFig22KirMungoftwleftVA(btecKarrow)-onelevelaboveprvtouBmgFig.24:CTAshowmvrtbrv11oubpxubwhitearrowB)thatcanbCoHfUMddoublelumenandftap.Fig.25:Samecaeagure24,oneICvelabove.Vectobraivenousplexus(Whftearrows)andvertebralartoryF.26:CTAdtsptaynorercaseofacreaceat-shapedvertebralvenousp*exusth£canbemndagnoscdasadtssccUonComparewHgure8.ToavoidttoPHfaI.ttrcomf11nddIoMowMxtntioctvbmFig.30:AxialT1withfatsuppress)nPerkXmCaWlvXMJtsuperiorsaturationbandShOWShighIlqnfllintensityvrtebraivenousplxus(whitearrow)thatcanmuybeCOnfbMd*Mhntrau>lhematoma(comparewithftgurc11).AhK)notethehighSignalIntCmitymIUqUlMvnsad>acttoroundflowVOtdIhafp<WBnt>ICA.Hg.31:CTAdisplayaletJugukMvein(Whrtearrow)acen(a*CA(weaow)thatsimulateadoubtelumenandflap“M：!4rvNMfqrTTagftt*suesnatabWrlJNotoEt»VtoBhikaccc*nS，0GIh*9aGM53.0mk4e>tM*vgwMMMcraraiCtMJbar4gmwfcMeatag”CAJrIMJferB<rwGehr*NFig.35:AthefOBCteroCicplaqueCTAoflherightICATh5Iabucomponentsattheplace(w<ea0w9)cannmcIntramuralhealoma.PeripheralCdldflcalons(btocMarrows)CAfihoiptoeMthCofgdg11DssFig.3:CTA:axialsliceatthlevelofthnghtPrOXIrTMBlICA.ArwrOICierOtrplaquClcle三yshowsIhdtthesuittissuecomponent(whitearrows)hasavastIpidcore(-25UH)NotealsoBOfnOpripffll00catiorm(blockarrows)RgPw4*'w-l>eCTArNr8Qkrb"tw>arctaplh4eUccVAHMe*Mfrcrt4rafwrtry.arcnm,¾tefc*.a*rav六、治疗由子CAD可导致不同的临床病变，包括脑神经病变、急性缺血性卒中及蛛网膜下腔出血等，因此治疗方案依不同疾病而定。出现复发性短暂性脑缺血发作、卒中或死亡，主要发生在夹层形成后的前几周。CAD导致急性缺l性B卒中：溶栓、抗凝/抗血板；血管内介入治疗，包括颊动脉近端闭塞、动脉瘤栓塞；手术治疗，包括病变动脉切除、静脉血管替代、血栓处内膜剥脱术及血管补片治疗。脑卒中的预后与初始缺血损伤的严重程度和侧支循环的?EH有关。-CAD总死亡率在2c5%之间，预后T殳良好，I803(j至90%的病例无后遗症颈部动脉夹层-小结 定义是颈部动脉内膜撕裂导致血液流入其管壁内形成壁内血肿，继而引起动脉狭窄、闭塞或动脉瘤样改变。 好发于颅外段颈动脉及椎动脉的活动度大的节段。 是年龄小于45岁的患者卒中的重要病因（20%） 影像表现为：动脉偏心性狭窄伴外管径扩张、串珠征或节段性狭窄、双腔征、内膜瓣、动脉瘤样扩张。高分辨MRl壁间血肿典型表现为新月形高信号。-JZ
