中枢神经系统影像.ppt

中枢神经系统影像学表现NeuroimagingoftheCentralNervousSystem,学习内容：颅脑、脊髓、血管,1.不同成像技术的特点和临床应用,2.正常影像学表现,3.基本病变影像学表现,4.影像新技术,不同成像技术的特点和临床应用,1.X线图像的特点,2.CT图像的特点,3.MR图像的特点,4.DSA检查,中枢神经系统正常影像学表现AnatomyoftheCentralNervousSystemwithNeuroimaging,正常影像学表现,颅脑,头颅X线平片,颅骨最基本的影像学检查方法显示颅骨骨质改变，是诊断颅骨骨折和骨缝分离的有效方法,特点,局限性,仅提示病变存在，但不能确诊临床表现明显但无异常发现,计算机体层摄影（CT）,CT图像的特点,局限性,断层图像不利于器官结构和病灶的整体显示CT检查对疾病的定性诊断仍有一定限度CT检查使用X线，具有辐射性损伤,是目前常用的影像学检查方法常规CT图像采用横断层图像，克服了普通X线检查各种组织结构重叠干扰的影响分辨率高，对比度强,CT定位像,扫描基线：采用眦耳线（即眼外眦与外耳道中心的联线），层厚8-10mm，共9-12层,大脑：额叶颞叶顶叶枕叶基底节丘脑,幕上,小脑：半球、蚓部脑干：中脑延髓桥脑,幕下,脑实质,双侧脑室第三脑室第四脑室,脑室系统,鞍上池环池桥小脑池枕大池外侧裂池大脑纵裂池,脑池系统,脑室脑池系统,磁共振成像（MRI）,优势：组织分辨率高任意平面成像多种参数、序列成像,缺点：扫描时间长MRI对钙化不敏感个别患者有幽闭恐惧症，MRI检查有禁忌症,中枢神经系统基本病变CommonPresentationofNeurologicalDisease,XPlain,颅高压征：颅缝增宽，脑回压迹增深颅骨：破坏，增生蝶鞍：扩大、吸收、变形钙化：,DSA,颅内占位使血管移位脑血管形态改变,计算机体层摄影（CT）,密度异常:低密度、等密度、高密度、混杂密度增强特征:不强化、轻中度强化、明显强化脑结构改变:占位效应脑萎缩脑水肿、脑积水颅骨改变：骨质破坏、增生、吸收、骨折,计算机体层摄影（CT）,常规CT通过密度的变化反应信息,0,-1000,+1000,-10,-20,-30,-40,-60,-50,-70,-80,-990,-980,10,20,30,40,50,60,70,990,980,970,960,水,空气,骨,-90,脂肪,软组织,1）低密度病变：,脑水肿脑梗塞、脑软化脑肿瘤炎性病变慢性血肿,颅内疾病的平扫基本CT征象,2）等密度病变：,脑肿瘤脑梗塞的等密度期颅内血肿的等密度期(亚急性出血),颅内疾病的平扫基本CT征象,3)高密度病变,颅内血肿钙化肿瘤炎性肉芽肿,颅内疾病的平扫基本CT征象,4)混杂密度病变,脑肿瘤（颅咽管瘤、恶性胶质瘤、畸胎瘤）出血性脑梗塞炎性病变,颅内疾病的平扫基本CT征象,磁共振成像（MRI）,MRI通过磁共振信号的变化反应信息,人体不同器官的正常组织与病理组织的T1和T2是相对恒定的，而且它们之间有一定的差别，这种组织间驰豫时间上的差别，是MRI成像基础,基本病变信号特征,目的:,病灶强化方式:明显强化、中度强化、轻度强化、不强化,显示平扫未发现病灶；了解病灶血供情况；区别肿瘤和瘤周水肿；有利诊断和鉴别诊断,增强检查,增强检查,CT:对比剂:含碘非离子型造影剂剂量:50-100ml注射速率：1-2ml/sec注射方式:人工手推或高压器注射,MRI:对比剂:顺磁性造影剂：Gd-DTPA剂量:15-30ml注射速率：1-2ml/sec注射方式:人工手推或高压器注射,脊髓和椎管内病变,SpineCommonimagingmethod,*Plainfilm(平片)*Myelography（脊髓造影）*Spinalangiography（脊髓血管造影）*Computedtomography*Magneticresonanceimaging,SPINE,脊髓MRI,检查方法以矢状面为主，辅以横断面和冠状面，确定病变的三维关系，方法有平扫和增强影像观察和分析正常脊髓灰质、白质及脑脊液信号特点与颅内脑质及脑脊液一致,脊髓,检查方法以矢状面为主，辅以横断面和冠状面，确定病变的三维关系，方法有平扫和增强扫描影像观察与分析正常脊髓灰质、白质与脑脊液信号特点与颅内脑实质与脑脊液信号一致,脊髓基本病变,脊髓外形异常：脊髓增粗、萎缩脊髓密度（信号）异常：局限性、弥漫性蛛网膜下腔形态异常：,可分为出血性和非出血性损伤，MRI可直观地显示脊髓损伤的部位、范围、类型和程度脊髓水肿：T1WI等、低信号，T2WI高信号出血：T1WI和T2WI均为高信号脊髓软化、囊变、空洞：T1WI低信号，T2WI高信号脊髓萎缩：脊髓变细,脊髓损伤,脑血管成像(Cerebralvascularangiography),DSA(digitalsubstractionangiography)CTA(computedtomographyangiography)MRA(magneticresonanceangiography),DSA(数字减影血管造影),颈内动脉、椎动脉、颈外动脉血管显示Vertebrobasilarartery(VA)椎基动脉Internalcarotidartery(ICA)颈内动脉Extenalcorotidartery(ECA)颈外动脉Willis环:大脑前动脉,大脑后动脉,前后交动脉,颈内动脉末端诊断动脉瘤、动静脉畸形、肿瘤血供,Vertebrobasilarartery(VA)椎基动脉Internalcarotidartery(ICA)颈内动脉Extenalcorotidartery(ECA)颈外动脉Willis环:大脑前动脉,大脑后动脉,前后交通动脉,颈内动脉末端,Advantageof64sliceVCT：CTA,DiseasesofCNS,Vasculardiseases血管病变：hemorrhage,infarct(ischemicinfarct,hemorrhagicinfarct,lacunarinfarct)Infectiousdiseases感染性病变VascularMalformality血管畸形,Vasculardiseases血管疾病,AcuteIntracerebralHemorrhage急性脑出血,临床表现Clinicalfindings:Hypertension,Vascularmalformation,Aneurysm,Hematopathy,Tumor影像学表现ImagingfindingsCT:Location,Density,SecondarysignsMR:Location,Signal,Secondarysigns鉴别诊断DifferentialDiagnosis,EvolutionofHematomaonCT血肿在CT上的演变,Acutehematoma:4hrsafterictus急性脑血肿：发病后4小时,4daysafterictus发病后4天,3monthsafterinitialCT首次CT后3个月,EvolutionofHematomaonCT血肿在CT上的演变,10,40,50,60,70,80,20,30,1,2,3,4,5,6,7,8,9,10,11,12,13,14,ISODENSE,HYPERDENSE,HYPODENSE,DecreasingDensityofHematoma血肿密度的下降,DensityComparedtoCortex,TimeinDays,IntracerebralHemorrhageImagingfindings,CT:1)Location:高血压性脑出血基底节区多见2)Density:急性期高密度，随时间推移密度渐减低3)Secondarysigns：占位效应明显，可破入脑室、蛛网膜下腔，继发阻塞性脑积水MRI：不同的出血时间信号不同，反映血肿内血红蛋白、氧合血红蛋白、脱氧血红蛋白、正铁血红蛋白、含铁血黄素的演变过程超急性期（6h):氧合血红蛋白（T1WI等，T2WI高信号）急性期（7-72h）：脱氧血红蛋白（T1WI等或略低，T2WI低信号）亚急性期（3d-2W）:正铁血经蛋白（T1WI高信号，T2WI高信号）慢性期（2W后）：含铁血黄素（T1WI低，T2WI低信号）,BloodProducts血肿,AcutehematomawellseenonCT急性血肿宜用CT观察,SubacuteandchronichematomabetterevaluatedonMRI亚急性和慢性血肿宜用MRI观察,Primary(hypertensive)bleedsoccurinthebasalganglia;forbleedsatotherlocations,huntforacause高血压出血常在基底节；其它部位的话要寻找病因,BrainInfarction脑梗塞,临床表现Clinicalfindings:Thrombosis,Embolism,Hypotension,Highpour-pointstate影像学表现ImagingfindingsCTMR:Ischemicinfarct;Hemorrhagicinfarct;Lacunarinfarct鉴别诊断DifferentialDiagnosis,左侧大脑前动脉闭塞致左侧额上回脑梗塞：CT平扫示左侧额上回长条状低密度区（），边界较清，轻度占位表现,左侧枕叶大脑后动脉梗塞：CT平扫示左侧枕叶低密度区，未见明显占位表现,左侧大脑中动脉梗塞：CT平扫示左颞顶叶大片低密度区，边界清晰，密度与脑脊液相似，左侧脑室扩大，中线结构无移位。,右侧额后顶前出血性脑梗塞：CT平扫示右额顶叶大片低密度区内散在不规则高密度出血灶,Foggingeffect模糊效应:缺血性脑梗塞2-3周时病灶变为等密度而不可见Lacunarbraininfarction腔隙性脑梗塞：深部髓质小动脉闭塞所致，大小约10-15mm，好发于基底节、丘脑、小脑和脑干。Hemorrhagictransformationafterinfarction出血性脑梗塞：CT示在低密度脑梗塞灶内，出现不规则斑点、片状高密度出血灶。,Cerebralinfarctionimagingfindings,CT:24h内，CT可无阳性发现，或显示脑沟回模糊；动脉致密征；岛带征。24h后，与闭塞血管供血区一致，同时累及皮层和髓质，呈底在外的三角形或楔形低密度，边缘不清，常并发脑水肿，病灶大时可出现轻度占位效应。4-6周，边缘清楚、近于脑脊液密度的囊腔,1个月后可出现脑萎缩。出血性脑梗塞：扇形低密度梗塞区内出现不规则高密度出血斑。腔隙性梗塞：好发于基底节区，因小的终末动脉闭塞所致，表现为直径小于15mm低密度灶，边缘清楚。MRI：较早发现病变,SubcorticalarterioscleroticencephalopathyBingswangersdisease皮层下动脉硬化性脑病,临床表现Clinicalfindings影像学表现ImagingfindingsCTMR鉴别诊断DifferentialDiagnosis,Infectiousdiseases感染性疾病,Pathogens:Bacterium,Virus,Fungi,ParasitePathology:Meningitis,Encephalitis,Veininflammation,Brainabscess脑脓肿,临床表现Clinicalfindings:Otogenic,Blood-borne,Traumatic,Cryptogenic影像学表现ImagingfindingsCTMR鉴别诊断DifferentialDiagnosis,BrainabscessImagingfindingonCT,CT1、急性炎症期：平扫大片低密度灶，边界模糊，伴占位效应，增强无强化2、化脓坏死期：平扫低密度区内出现更低密度坏死灶，增强呈不均匀强化3、脓肿形成期：平扫见等密度环，内为低密度脓肿并可有气泡影；增强呈环形强化，其壁完整、光滑、均匀，或多房分隔,BrainabscessImagingfindingonMR,MR1、脓腔呈长T1和长T2异常信号2、增强呈薄壁环形强化，内外壁光滑,Tuberculosis,CNS,临床表现Clinicalfindings影像学表现ImagingfindingsCTMR鉴别诊断DifferentialDiagnosis,TuberculousmeningistisandencephalitisImagingfindings,CT平扫：1、早期无异常发现2、脑底池炎性渗出表现为脑底池密度升高3、脑内结核：脑内以基底节区多见呈低或等密度灶4、脑积水增强：脑膜增厚强化，结核球呈结节状或环形强化,TuberculousmeningistisandencephalitisImagingfindings,MR平扫：1、脑底池T1WI信号升高，T2WI信号更高，抑水T2WI显示病灶更清楚，高信号2、脑内结核球T1WI呈略低信号，T2WI呈低、等或略高混杂信号，周围水肿轻3、脑积水增强：脑膜明显增厚强化，结核球呈结节状强化或环状强化,cerebralcysticercosisimagingfinding,分型：脑实质型；脑室型、脑膜型、混合型CT：脑内多发低密度小囊，囊腔内可见致密小点状囊虫头节，囊虫死亡后呈高密度点状钙化MR：脑内多发小囊，小囊主体呈长T1长T2信号，其内偏心结节呈短T1和长T2信号增强：囊壁与头节可轻度强化,VascularDeformality血管畸形,Aneurysm血管瘤,临床表现Clinicalfindings:headache影像学表现ImagingfindingsCT:1)Directsigns:nothrombosis;partofthrombosis;totallythrombosis2)Secondarysigns:subarachnoidhemorrhage,hematoma,hydrocephalus,encephaledema,infarctMR:DSA鉴别诊断DifferentialDiagnosis,BrainArteriovenousMalformations脑动静脉畸形,临床表现Clinicalfindings影像学表现ImagingfindingsCTMRDSA鉴别诊断DifferentialDiagnosis,TraumaticBrainInjury-CT,TraumaticBrainInjury-ClinicalFeatures,SignsandSymptomsofheadinjurycanincludeanycombinationofthefollowing:loseconsciousnessVomitingSeizureWeaknessHeadacheInabilitytospeakAmnesia健忘症,CNStraumaClinicalFeatures-consciousness,NoLossofconsciousness(L.O.C)(SDH，EDH?，NotDAI弥漫性轴索损伤)Awakeatthescene，DelayedLOC(SDH，EDH，Swelling，NotDAI)TransientLOC-Wake-up-DelayedLOC(“Classic”lucidintervalforEDH)ContinuousLOCFollowingImpact(“Classic”shearing/DiffuseAxonalinjuryDAI弥漫性轴索损伤),ImmediateunenhancedheadCTscanistheprocedureofchoicefordiagnosisheadinjuryComputedtomography(CT)：itisquick,accurate,andwidelyavailableHeadCTscancanshowlocation,volume,effectofthelesionsofintracranialinjuries.,ClassificationofHeadInjury：-centripetalapproachousidetoinside,Extracerebralinjury:Scalp-hematoma头皮血肿Calvarium-skullfracture颅骨骨折Epiduralhematoma(EDH)硬膜外血肿Subduralhematoma(SDH)硬膜下血肿Subarachnoidhemorrhage(SAH)蛛网膜下腔出血Intracerebralinjury:Braincontusion(edema,hemorrhage)脑挫伤Intraventricular-hemorrhage（脑室出血）,1.Skullfracture2.Epiduralhematoma3.EpiduralHematoma4.SubduralEffusion5.Subarachnoidhemorrhage6.CerebralCorticalContusion7.Diffuseaxonalinjury8.SequelaeofHeadInjury,闭合性脑损伤的机制,冲击伤,作用力接触力惯性力,原因直接碰撞减速或加速运动,脑损伤范围局部多处弥散性,受伤时头部状态固定不动运动中,对冲伤,1.Skullfracture骨折,部位形态与外界关系,颅盖骨折颅底骨折线性骨折凹陷性骨折粉碎性骨折开放性骨折闭合性骨折,分类,Linearfracture线型骨折：AxialCTisnotgoodforlinearfractureShouldcarefullytoidentifythefracturelineDepressionfracture凹陷型骨折：AmoreseriousfractureDownwarddisplacementoftheskullbonespressesdirectlyonbraintissueandcausedtheinjuryCTisimportantforthefractureandotherassociatedintracraniallesionsBonewindowtoevaluatefracture,Skullfracture骨折,CT,骨窗观察,线形骨折的临床表现,累及眶顶和筛骨：鼻出血眶周广泛淤血斑，“熊猫眼”征广泛球结膜下淤血斑、脑膜、骨膜均破裂：脑脊液鼻漏筛板或视神经管骨折：嗅神经或视神经损伤,累及蝶骨：鼻出血，脑脊液鼻漏累及颞骨岩部：脑脊液耳漏、VII/VIII脑神经损伤蝶骨、颞骨内侧部损伤：垂体/II-VI脑神经损伤累及颈内动脉海绵窦部：颈内动脉海绵窦瘘累及破裂孔或颈内动脉管：致命性鼻出血、耳出血,累及颞骨岩部后外侧：Battle征，乳突部皮下淤血累及枕骨基底部：枕下肿胀、皮下淤血斑枕骨大孔或岩尖后缘附近骨折：IX-XII脑神经损伤,颅底部线形骨折,颅盖部发生率高,颅前窝骨折累及眶顶和筛骨，可伴有鼻出血、眶周广泛淤血(称“眼镜”征或“熊猫眼”征)以及广泛球结膜下淤血。如硬脑膜及骨膜均破裂，则伴有脑脊液鼻漏，脑脊液经额窦或筛窦由鼻孔流出。若骨折线通过筛板或视神经管，可合并嗅神经或视神经损伤。颅中窝骨折颅底骨折发生在颅中窝，如累及蝶骨，可有鼻出血或合并脑脊液鼻漏，脑脊液经蝶窦由鼻孔流出。如累及颞骨岩部，硬脑膜、骨膜及鼓膜均破裂时，则合并脑脊液耳漏，脑脊液经中耳由外耳道流出；如鼓膜完整，脑脊液则经咽鼓管流向鼻咽部而被误认为鼻漏。骨折时常合并有第、脑神经损伤。如骨折线通过蝶骨和颞骨的内侧面，尚能伤及垂体或第、V、脑神经。如骨折伤及颈动脉海绵窦段，可因颈内动脉海绵窦瘘的形成而出现搏动性突眼及颅内杂音。破裂孔或颈内动脉管处的破裂，可发生致命性鼻出血或耳出血。颅后窝骨折骨折线通过颞骨岩部后外侧时，多在伤后数小时至2日内出现乳突部皮下淤血(称Battle征巴特耳征)。骨折线通过枕骨鳞部和基底部，可在伤后数小时出现枕下部头皮肿胀，骨折线尚可经过颞骨岩部向前达颅中窝底。骨折线累及斜坡时，可于咽后壁出现黏膜下淤血。枕骨大孔或岩骨后部骨折，可合并后组脑神经()损伤症状。,WhatisEpiduralhematoma？硬膜外血肿EDHisatraumaticaccumulationofbloodbetweentheinnertableoftheskullandthestripped-offduralmembrane.WhatisSubduralhematoma？硬膜下血肿SDHisaformoftraumaticbraininjuryinwhichbloodgatherswithintheinnermeningeallayerofthedura.,dura,2Epiduralhematoma(硬膜外血肿),DirecttraumatocraniumFracture(90%)-Laceration（撕裂）ofMeningealA.andV.Locationis66%temporo-parietal（颞顶部）TemporalBone(70-80%)lucidinterval（中间清醒期40%pts）Mortality（死亡率）of15-30%硬脑膜外血肿病人意识变化的典型特征是:昏迷一清醒一再昏迷,即意识障碍有中间清醒期,伤后有短暂的原发性昏迷,在血肿位形成前意识恢复,当血肿形成增大,颅内压增高可出现再次昏迷,硬膜外血肿（EDH）：颅内血肿积聚于颅骨与硬膜之间,Epiduralhematoma-CT,1.Smoothlymarginated,lenticular透镜状,orbiconvex双凸homogenoushyperdense高密度lesion2.Rarelycrossesthesuturelinebecausetheduraisattachedmorefirmlytotheskullatsutures（缝）.3.Frequentincidenceofassociatedskullfracture（90%）-fractureline,AcuteEpiduralHematoma,Thehematomastillcontainsuncoagulatedblood,orstillhasactivebleeding.血肿包含不凝血或活动出血Round,stream-likefillingdefectsmaybeseeninthehemotoma血肿内可见圆形密度减低影,.,3EpiduralHematoma硬膜下血肿,ScoureofbloodLaceration（撕裂）ofCortical（脑皮层血管）AA.andVV.(Direct:penetratinginjury)(直接穿透伤)Bridging(Cortical)Veins（桥静脉）Duralsinus（静脉窦）LargeContusions(Direct/indirect:PulpedBrain,硬膜下血肿（SDH）：颅内出血积聚于硬脑膜和蛛网膜下腔之间,SubduralHematoma硬膜下血肿Presentation,Significantheadtrauma,butchronicsubdural-onlyminororremotehistoryoftraumaBilateralin20%adults(commoninelderly),80-85%bilateralininfantsExtensionintointerhemisphericfissure（纵裂），tentorial（小脑幕）marginsBraininjuryin50%;ComplexInjury(DAI)Skullfractureinonly1%,SubduralHematoma-CT,1.Sickle-shape(镰刀型)ornewlunarshape(新月型)2.Extendspastthesutures3.AcuteSDH-HyperdenseSubacuteSDH-Isodense(1-2weeks)ChronicSDHHypordense4.Braininjuryin50%;ComplexInjury(DAI);5.Skullfractureinonly1%,AcuteSubduralHematoma急性硬膜下血肿,Thehematomamayextendingintothesubduralspaceoftentorialregion.血肿可以延伸到小脑幕区.,AcuteSubduralHematoma,Thehematomamayextendingintotheinterhemisphericfissure血肿延伸至大脑镰部.,ChronicSubduralHematoma慢性硬膜下血肿,Shape：Semilunar，fusiform，Ovalshape外形：半月形、纺锤形、椭圆形.Density：HyperdenseIsodenseHypodenseMixeddensity密度：高密度、等密度、低密度、混杂密度,IsodenseChronicsubduralhematoma,等密度慢性硬膜下血肿.,Hyperintensityofchronicsubduralhematoma高密度慢性硬膜下血肿（T1/T2均为高信号）,.,等密度硬膜下血肿,双侧脑室对称变小，体部呈长条状两侧侧脑室前角内聚，夹角变小，呈“兔耳征”脑白质变窄塌陷皮层脑沟消失,MembraneHematoma,EpiduralAcuteBiconvexUnilateralSkullFracture90%LimitedbysuturesDirecttraumatocraniumLaceration（撕裂）ofMeningealArterylucidinterval（中间清醒期40%pts）,SubduralAcutetoChronicNewlunarshapeBilateralFracture+/-1%CrosssuturesContrecoupInjury对冲伤Laceration（撕裂）ofBridgingVeins（桥静脉）,4.SubduralEffusion硬膜下积液,SubduralEffusion硬膜下积液,Occurredinagedpatientorinfant发生在老人及幼儿.Developedseveraldayslaterafteraheadinjury外伤几天后形成Oftenbilateral常双侧Spontaneouslyresorbed自发吸收.Craniotomy,V-Pshunt,meningitisalsomaycausesubduraleffusion穿颅术、VP、脑膜炎也可发生.,5.Subarachnoidhemorrhage（蛛网膜下腔出血）,Subarachnoidhemorrhage,ThesensitivityofCThasbeenreportedtorangefrom85to100%.Highdensitylesionwasdemonstratedincerebralcisterns（Subarachnoidspaceovercerebralconvexity，Suprasellacistem（鞍上池），interpeduncularcistern（脚间池），pontinecistern，cisternofthelateralfissure（侧裂池）byplainCTscanComputedtomography(CT)isthemethodofchoicetodetectacutesubarachnoidhemorrhage(SAH).,Linearhighdensityinthesubarachnoidspaces(sulci，fissures，cistems)OftenassociateswithotherintracerebralorextracerebrallesionsMaycausehydrocephalus,Subarachnoidhemorrhage（SAH,蛛网膜下腔出血）-CT,Subarachnoidhemorrhage-MRI,Magneticresonanceimaging(MRI)usingFLAIRsequencesshowsacomparablesensitivityinacuteSAHevenbesuperiortoCT.(hyperintenseonT2FLAIR)InsubacuteSAH,startingfromday5afterthesuspectedhemorrhage,thesensitivityofMRIisclearlysuperiortoCT.(hyperintenseonT1WIandT2WI),纵裂池、脑沟SAH,SAH一引起交通性脑积水.,交通性脑积水.,2.6TraumaticSAHinthesulci,interhemisphericfissure9.10Communicatinghydrocephalus,6.CerebralCorticalContusion（脑挫伤）,CerebralCorticalContusion,PresentationLossofconsciousness，headache，mentalstatuschangeUsuallyinasuperficialcorticallocation50%occurintemporallobe33%infrontallobe(frontalpoleandinferiorsurface)Delayedhemorrhageseenin20%,7.Diffuseaxonalinjury（弥漫性轴索损伤）,Followsseveredeceleratingclosedheadtrauma,patientsaregenerallyunconsciousfromthetimeoftheeventLocationofinjuriesaretypicallyinareasoflargenumbersofparallelaxonssuchasthecorpuscallosum,internalcapsule,brainstem,basalgangliaandsubcorticalwhitematter,Diffuseaxonalinjury（弥漫性轴索损伤）,Usuallypunctatehyperdensitiesareseeninthecorpuscallosum,graywhiteinterfaces,androstralbrainstemTheaxonalinjuryitselfisnotvisualized,buttheassociatedmicro(andmacro)hemorrhagesinthecharacteristicdistributionareseen,Diffuseaxonalinjury-CT,Detectingandcharacterizingbrainstemlesions,specificallyandpredominatelynon-hemorrhagiccontusionsAppearancedependsonpresenceorabsenceofhemorrhageT1-weightedsequencesoftennormal;multiplehyperintensefociatgray-whitejunctionsandcorpuscallosumonT2WI,DiffuseAxonalInjury-MRI,0353骑摩托车与另一摩托车相撞，入院时为浅昏迷，GCS评分6分，20天后甚至转清，未能言语.0366言语模糊，乱语，03616复查时对答正常上图：伤后4天MRI检查下图：伤后43天复查,Soonafterheadinjury8hourlater,DelayedHemorrhage迟发血肿,Brainatrophy,duetobraincontusionCommunicatinghydrocephalus,duetoSAH，IVHEncephalomalaciaorporencephaliccyst，duetobraincontusion,脑挫裂伤所致的：脑萎缩.,交通性脑积水.,脑软化、脑穿通囊肿.,8.SequelaeofHeadInjury脑外伤后遗症,颅脑外伤的影像诊断注意点,1.颅脑外伤首选CT检查，但病情与CT表现不符时，要行MRI检查；2.病情有变化时，随时复查CT。,答案:AADA,答案：CDDCB,答案：ECAE,颅内肿瘤/椎管内肿瘤影像诊断Intracranialandintraspinaltumorradiology,脑肿瘤/椎管内肿瘤Intracranialandintraspinaltumor,CT：Withorwithouttumor，localizationandqualitativediagnosisAdvantagesofMRI：Noboneartifacts,multi-dimensionalsectionsscanning,avarietyofimagingparameters。Therefore,amoreaccuratepositioningandcharacterizationofthetumor,Imagingsignsofintracranialtumors,Directsigns：1）Thesiteoftumor2）Thedensity(signal)oftumor3）Thenumber,size,shapeandedgeoftumor4）TheenhancementextentandmorphologyoftumorIndirectsigns：1）Peritumoraledema2）ChangesinskullTheexpandanddamageinternalauditorycanalcanbeseeninacousticneuromaTheskullcorrespondingshowsthickeningofmeningiomas,星形细胞瘤（astrocytictumors),AstrocytictumorsisthemostcommonprimaryintracerebraltumoursAstrocytomainadultsmorecommoninSupratentorial,childrenmorecommonininfratentorialcerebellarAstrocytomamainlylocatedinthewhitematter,grading-Tumorlocalizationsignsandsymptomsofintracranialhypertension,Epilepsy,脑内肿瘤直接征象1）好发部位:白质2）密度（信号）：级低密度，级高低混杂密度的囊性肿块，可有钙化与瘤内出血、坏死、囊变3）数目、大小、形态和边缘：级边界清楚，级边界不清，形态不规则4）增强的程度及形态：级不强化，级呈不规则环形伴壁结节强化间接征象1）瘤旁水肿：明显2）颅骨变化：常无,星形细胞瘤astrocytictumorsgrade,脑膜瘤Meningioma,Meningiomaoriginatedfromarachnoidgranulationscapcells,connectedwiththeduraMosttumorsoccuroutsidethebrain,somecanoccureveninventricleAtypicalsitefollowedbyfrequencyofoccurrence:,脑膜瘤影像特征总结,脑外肿瘤直接征象1）好发部位:矢状窦旁、脑凸面、蝶骨嵴、嗅沟、桥小脑角、大脑镰或小脑幕2）密度（信号）：CT平扫等或略高密度、常见斑点状钙化3）数目、大小、形态和边缘：类圆形，边界清，常以广基底与硬膜相连，表现成增厚强化的“脑膜尾征，脑组织受压形成”皮层扣压征“4）增强的程度及形态：均匀性显著强化,脑膜瘤影像特征总结,间接征象：1）瘤旁水肿：轻或无，静脉或静脉窦受压时可出现中或重度水肿2）颅骨变化：脑膜瘤可见相应颅骨增厚,AtypicalMeningioma,1)全瘤以囊性为主2）肿瘤内密度不均匀3）壁结节4）瘤内有高密度出血5）肿瘤完全钙化6）全瘤密度低，并呈不均匀强化7）环形强化8）骨化性脑膜瘤9）瘤周脑脊液样低密度区10）酷似脑内的肿瘤11）多发性脑膜瘤,Meningioma,DifferentialdiagnosisCerebralconvexityandfalxmeningiomas：Metastases,malignantlymphoma,anaplasticastrocytomaSuprasellarregionandtheanteriorcranialfossameningiomaMiddlecranialfossameningiomaPosteriorfossameningiomaIntraventricularmeningioma,垂体腺瘤（pituitaryadenoma),Clinicalsymptoms：Compressionsymptoms；EndocrinedisorderPathology:Outsidethebrain;Encapsulated,pituitaryadenoma,pituitarymicroadenoma:10mm,Limitedtotheintrasellarpituitarymacroadenoma:10mm,pituitarymicroadenoma,Directsigns：Abnormaldensity（orsignal)withinthepituitaryAftertreatment,thetumorshrink,higherdensityIndirectsigns3)Pituitaryheightabnormaly4)Bulgeontheupperedgeorcollapseoftheloweredgeofthepituitary5)Pituitarystalkdeviation,垂体瘤的影像特征,脑外肿瘤直接征象1）好发部位:鞍内，可穿破鞍隔突入鞍上池、侵入蝶窦、侵入两侧海绵窦2）密度（信号）：CT平扫等或略高密度，易出血、坏死、囊变，偶见钙化3）数目、大小、形态和边缘：大于10mm为大腺瘤，哑铃状或葫芦状，有雪人征或束腰征4）增强的程度及形态：多数均匀、少数非均匀强化间接征象1）瘤旁水肿：无或少2）颅骨变化：常有蝶鞍扩大,pituitaryadenomadifferentialdiagnosis,pituitarymicroadenoma:Pituitarycysts,metastases,pituitaryabscess,pituitaryinfarctionpituitarymacroadenoma:Craniopharyngioma,meningioma,epidermoidcyst,arachnoidcyst,astrocytoma,aneurysm,颅咽管瘤（craniopharyngioma),Clinicalsymptoms：Childrenwithdevelopmentaldisorders,increasedintracranialpressure；Adultswithvision,visualfielddisorders,psychosisandhypopituitarismPathology:Cysticorpartiallycystic;Calcification,Imagingfeaturesofcraniopharyngioma,脑外肿瘤直接征象1）好发部位:鞍区，鞍上多见2）密度（信号）：CT平扫囊性或部分囊性为多，CT值变化较多（MRI混杂信号），含胆固醇多则低，含蛋白质与钙质多则高，沿囊壁壳状钙化3）数目、大小、形态和边缘：圆形或类圆形，边清4）增强的程度及形态：囊壁环状强化，实性部分呈均匀或不均匀强化间接征象1）瘤旁水肿：无或少2）颅骨变化：蝶鞍可扩大,craniopharyngiomadifferentialdiagnosis,Cysticcraniopharyngioma:epidermalcyst,dermoidcyst,teratoma,arachnoidcystSolidcraniopharyngioma:germinoma,astrocytoma,hamartoma,giantaneurysms,meningiomas,听神经瘤(Acousticneurinoma),Cerebellopontineangletumorsaccountforabout80%acousticneuroma