脑梗死的血管定位李怡

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,脑梗死的血管定位,齐鲁医院李怡,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,MCA,ACA,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，,1,4,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,2 mm,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,1,3,个皮质支外，还发出,2,3,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. Axial T2-weighted image(2500/80) reveals the presence of an inhomogeneous mass in the right lateral ventricle. The low signal intensity,suggets,the presence of calcification and hemorrhage.,E. Angiogram of the right internal carotid artery obtained on day 3 demonstrates a,hypervascular,mass fed from the right anterior,choroidal,artery (arrows).,Which one is the,Anterior,Choroidal,Artery,?,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,VA,BA,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）,Blood supply of the three subdivisions of the brainstem.,Diagram of major supply.,Sections through different levels of the brainstem indicating the territory supplied by each of the major brainstem arteries.,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,Patients with unilateral,paramedian,infarctions typically presented a pure motor,hemiparesis,that progressed over the first 3 days and was accompanied by,dysarthria,and,homolateral,ataxia.,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-,Gubler,Syndrome),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（,Foville,Syndrome),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（,Wallenberg syndrome),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。,Magnetic,resonance image of the fluid attenuated inversion recovery sequence for the axial (left) and T2 weighted coronal (right) sections. There is a well demarcated unilateral medial,medullary,infarct just below the,pontomedullary,junction. The right side of each image corresponds to the left side of the brain.,大脑动脉血管供血分区,CT,解剖,(,图文,),MCA,终末支,ACA,终末支,PCA,终末支,MCA,终末支,ACA,终末支,PCA,终末支,脉胳膜前动脉,MCA,终末支,ACA,终末支,PCA,终末支,脉胳膜前动脉,ACA,穿支,PCA,穿支及,PCoA,MCA,终末支,ACA,终末支,PCA,终末支,脉胳膜前动脉,ACA,穿支,PCA,穿支及,PCoA,MCA,穿支,MCA,终末支,ACA,终末支,PCA,终末支,脉胳膜前动脉,ACA,穿支,PCA,穿支及,PCoA,MCA,穿支,MCA,终末支,ACA,终末支,PCA,终末支,脉胳膜前动脉,ACA,穿支,PCA,穿支及,PCoA,MCA,穿支,MCA,终末支,ACA,终末支,PCA,终末支,MCA,终末支,ACA,终末支,PCA,终末支,MCA,终末支,ACA,终末支,PCA,终末支,MCA,终末支,ACA,终末支,ACA,终末支,脑的供血模式图,左枕叶梗死。（,PCA,终末支）,Figure 1: (a) Normal initial CT of the patient; (b) The cranial CT two days after the incident shows signal changes consistent with simultaneous infarcts in the right MCA and PCA areas; (c) In the digital subtraction angiography of the right ICA, PCA is seen to originate from the right ICA through,PCoA,i.e. fetal type PCA,PICA,On the left CT-images of a left-sided PICA-infarction.,Notice the posterior,extention,.,The infarction was the result of a dissection (blue arrow).,On the left CT-images of a,left-sided PICA-infarction,.,In unilateral infarcts there is always,a sharp delineation in the midline,because the superior,vermian,branches do not cross the midline, but have a,sagittal,course.,This sharp delineation may not be evident until the late phase of infarction.,In the early phase, edema may cross the midline and create diagnostic difficulties.,Infarctions at,pontine,level are usually,paramedian,and sharply defined because the branches of the basilar,arery,have a,sagittal,course and do not cross the midline.,Bilateral infarcts are rarely observed,because these patients do not survive long enough to be studied, but,sometimes small bilateral infarcts can be seen,.,SCA,On the left CT-images of a,cerebellar,infarction in the region of the superior,cerebellar,artery and,also in the brainstem in the territory of the PCA.,Notice the limitation to the midline.,ACA,：,A1 segment: from origin to anterior communicating artery and gives rise to medial,lenticulostriate,arteries (inferior parts of the head of the caudate and the anterior limb of the internal capsule).,A2 segment: from anterior communicating artery to bifurcation of,pericallosal,and,callosomarginal,arteries.,A3 segment: major branches (medial portions of frontal lobes, superior medial part of parietal lobes, anterior part of the corpus,callosum,).,Anterior,choroidal,artery,The territory of the anterior,choroidal,artery encompasses part of the hippocampus, the posterior limb of the internal capsule and extends upwards to an area lateral to the posterior part of the,cella,media.,The whole area is rarely involved in,AChA,infarcts.,On the left an uncommon infarction in the,hippocampal,region.,Part of the territory of the anterior,choroidal,artery and the PCA are involved.,Middle cerebral artery,The MCA has cortical branches and deep penetrating branches, which are called the lateral,lenticulo,-striate arteries.,The territory of the lateral,lenticulo,-striate perforating arteries of the MCA is indicated with a different color from the rest of the territory of the MCA because it is a well-defined area supplied by penetrating branches, which may be involved or spared in infarcts separately from the main cortical territory of the MCA.,On the left a T2W-image of a patient with an infarction,in the territory of the middle cerebral artery (MCA).,Notice that the lateral,lenticulo,-striate perforating arteries of the MCA are also involved (orange arrow).,On the left images of a hemorrhagic infarction in the area of the,deep perforating,lenticulostriate,branches of the MCA.,On the left enhanced CT-images of a patient with an infarction,in the territory of the middle cerebral artery (MCA).,There is extensive,gyral,enhancement (luxury perfusion).,Sometimes this luxury perfusion may lead to confusion with,tumoral,enhancement.,Posterior cerebral artery (PCA),Deep or proximal PCA strokes cause ischemia in the thalamus and/or midbrain, as well as in the cortex.,Superficial or distal PCA infarctions involve only cortical structures (4).,On the left a patient with acute vision loss in the right half of the visual field.,The CT demonstrates an infarction in the,contralateral,visual cortex,i.e,left occipital lobe.,There are two patterns of border zone infarcts:,1.Cortical border zone infarctions,Infarctions of the cortex and adjacent,subcortical,white matter located at the border zone of ACA/MCA and MCA/PCA,2.Internal border zone infarctions,Infarctions of the deep white matter of the,centrum,semiovale,and corona,radiata,at the border zone between,lenticulostriate,perforators and the deep penetrating cortical branches of the MCA or at the border zone of deep white matter branches of the MCA and the ACA.,On the left three consecutive CT-images of a patient with,an occlusion of the right internal carotid artery.,The,hypoperfusion,in the right hemisphere resulted in multiple internal border zone infarctions.,This pattern of deep watershed infarction is quite common and should urge you to examine the carotids.,On the left images of a patient who has small infarctions in the right hemisphere in the deep,borderzone,(blue arrowheads) and also in the cortical,borderzone,between the MCA- and PCA-territory (yellow arrows).,There is abnormal signal in the,right carotid (red arrow) as a result of occlusion,.,In patients with abnormalities that may indicate,borderzone,infarcts, always study the images of the carotid artery to look for abnormal signal.,On the left another example of small infarctions in the deep,borderzone,and in the cortical,borderzone,between the MCA- and PCA-territory in the left hemisphere.,On the left an example of infarctions in the deep,borderzone,and in the cortical,borderzone,between the ACA- and MCA-territory.,The abnormal signal intensity in the right carotid is the result of an occlusion.,This combination of findings is so common, that once you know the pattern, you will see it many times.,脉络膜前动脉供血区梗死,A 9-year-old previously healthy girl was admitted to the Emergency Room with an eight-hour history of sudden onset of severe headache. The pain was,pulsatile,and bilateral and not accompanied by other symptoms. There is no history of migraine, epilepsy or stroke. Parents reported that soon after the onset of the headache the patient became drowsy for about one hour. No trigger factor was identified. On the neurological examination, the patient was alert and well oriented with no other abnormalities but mild,nuchal,rigidity.,Computed tomography of the brain revealed hemorrhage in the right lateral ventricle (Fig 1) and gadolinium-enhanced magnetic resonance imaging study of the brain disclosed a heterogeneous lesion in the,mesial,portion of the right temporal lobe, above and inside the temporal horn of the lateral ventricle. The lesion extended until the,subependimary,area of the,trigono,of the right ventricle. The lesion was,hypointense,on T1 and T2-weighted images and enhanced with the contrast. Other,hyperintense,T1 and T2-weighted images lesions were seen in the right lateral ventricle suggesting bleeding. Magnetic resonance angiography and cerebral angiography disclosed an,arteriovenous,malformation in part of the choroid plexus, supplied by the anterior,choroidal,artery (Figs 2 and 3). The AVM was classified according to,Spetzler,grading system as grade 3 (deep venous drainage: 1; eloquence area: 0 and size: 2).,Lacunes,may be confused with other empty spaces, such as,enlarged,perivascular,Virchow-Robin spaces (VRS).,The VRS are extensions of the subarachnoid space that accompany vessels entering the brain parenchyma.,Widening of VRS often first occurs around penetrating arteries in the,substantia,perforata,and can be seen on transverse MRI slices around the anterior,commisure, even in young subjects (5).,On the left CT- and MR-images at the level of,the anterior,commisure,(blue arrows).,On the CT there is a,hypodense,area in the right hemisphere, which follows the signal intensity of CSF on T2W- and FLAIR-images, which is typical for widened VRS.,PRES,PRES is short for,Posterior Reversible Encephalopathy Syndrome,.,It is also known as reversible posterior,Leukoencephalopathy,syndrome RPLS.,It classically consists of potentially reversible,vasogenic,edema in the posterior circulation territories, but anterior circulation structures can also be involved (6).,Many causes have been described including hypertension,eclampsia,and preeclampsia, immunosuppressive medications such as cyclosporine.,The mechanism is not entirely understood but is thought to be related to a,hyperperfusion,state, with,blood-brain-barrier breakthrough,extravasation,of fluid potentially containing blood or macromolecules, and resulting cortical or,subcortical,edema.,The typical imaging findings of PRES are,most apparent,as,hyperintensity,on FLAIR images in the,parietooccipital,and posterior frontal cortical and,subcortical,white matter,;,less commonly, the,brainstem, basal ganglia, and cerebellum,are involved.,On the left images of a patient with reversible neurological symptoms.,The abnormalities are seen both in the posterior circulation as well as in the basal ganglia.,Continue.,Diagnosis: MELAS,谢谢,2010.06.22,