脑疝分类及影像学表现图解-课件.ppt

1、图解脑疝北京天坛医院神经内科杜万良（reflexhammer）1ppt课件脑疝n是指在颅内压增高的情况下，脑组织通过某些脑池向压力相对较低的部位移位的结果，即脑组织由其原来正常的位置而进入了一个异常的位置。2ppt课件脑疝的类型：na.大脑镰疝：一侧大脑半球占位病变可使同侧扣带回经大脑镰下缘疝入对侧，胼胝体受压下移。n小脑幕切迹疝 b.前疝：也称颞叶沟回疝，是颞叶沟回疝于脚间池及环池的前部；后疝：颞叶内侧部疝于四叠体池及环池的后部；f.小脑幕切迹上疝：后颅凹占位病变时，小脑上蚓部可向上疝入小脑幕切迹的四叠体池。nc.中心疝：幕上压力增高，致使大脑深部结构及脑干纵轴牵张移位。nd.颅外疝：脑组织

2、通过颅外缺损疝出。ne.枕骨大孔疝：后颅凹占位病变时，可致小脑扁桃体疝入枕骨大孔。ng.蝶骨嵴疝：颅前凹和颅中凹的占位病变，由于病变部压力相对高一些，则额眶回可越过蝶骨嵴进入颅中凹，可颞叶前部挤向颅前凹。3ppt课件示意图na)subfalcial(cingulate)herniation;镰下疝nb)uncal herniation;钩疝nc)downward(central,transtentorial)herniation;下行性小脑幕疝nd)external herniation;颅外疝ne)tonsillar herniation.扁桃体疝nf)ascending transtent

3、orial herniation(reversed tentorial)上行性小脑幕疝ng)sphenoid herniation蝶骨嵴疝4ppt课件类型5ppt课件示意图6ppt课件解剖关系7ppt课件解剖关系FQcMb3vTOSyCClvFPOSpCClvss8ppt课件解剖关系FTCesPd4th VFTMbCes9ppt课件The suprasellar cistern&the quadrigeminal cisternnThe left and center images show the suprasellar cistern.Its anterior borders are fo

4、rmed by the frontal lobes(F).Its lateral borders are formed by the uncus(U)of the temporal lobes.The left image shows the 5-pointed star appearance of the suprasellar cistern where the posterior border is formed by the pons(Po).The black arrow points to the fourth ventricle.The center image shows a

5、higher cut where the suprasellar cistern has a 6-pointed star appearance since the posterior border is formed by the cerebral peduncles(P)which have a central cleft.nThe right image shows the quadrigeminal cistern(black arrow).Note the babys bottom appearance of its anterior border.When ICP is incre

6、ased,the quadrigeminal cistern space is compressed or obliterated.10ppt课件The suprasellar cistern&the quadrigeminal cistern.nThe midline sagittal MRI scan shows the levels of the axial diagrams.The quadrigeminal cistern is located above(anterior to)the Q in the highest cut shown(number 9).The anterio

7、r border of the quadrigeminal cistern is formed by the superior colliculi(c).Image 8(lower cut)also shows the quadrigeminal cistern.In this case,its anterior border is formed by the inferior colliculi(c).This gives the anterior border of the quadrigeminal cistern the appearance of a babys bottom.The

8、 quadrigeminal plate is comprised of the superior and inferior colliculi.The quadrigeminal cistern is posterior to this quadrigeminal plate,thus its anterior border may be formed by the inferior or superior colliculi.11ppt课件镰下疝12ppt课件Subfalcine herniation(cingulate herniation)Transtentorial herniati

9、on nThe suprasellar cistern(left image)is obliterated.The quadrigeminal cistern is very compressed and pushed posteriorly(center image).nA subdural hematoma with a midline shift is noted.There is central transtentorial and subfalcine herniation.13ppt课件ACA供血区梗塞14ppt课件Uncal herniation15ppt课件鞍上池缺角16ppt

10、课件冠状位CT与MRI17ppt课件海马旁回褶皱18ppt课件对侧颞角增宽19ppt课件同侧桥前池增宽20ppt课件同侧环池增宽21ppt课件Uncal herniation22ppt课件Uncal herniationnobliteration of the suprasellar cistern(red arrow)and the quadrigeminal cistern(green arrow)23ppt课件Uncal herniationnThe ipsilateral ventricle,sulci,fissures are compressed and obliterated,i

11、sappeared.nobliteration of the suprasellar cistern(s)and quadrigeminal cistern(q)24ppt课件Uncal herniationnAcute infarctionn1st daynAcute infarction n4th daysq25ppt课件Uncal herniationnBefore surgery,a big GBM in the left temporal lobe with uncal herniation.nAfter surgery,the GBM was removed,the suprase

12、llar cistern and quadrigeminal cisterns are normal.26ppt课件Uncal herniationnAcute infarction of right posterior artery(PCA),this is a complication of uncal/transtentorial herniation,because the PCA was compressed by brain herniation.27ppt课件双侧大脑后动脉梗塞28ppt课件双侧大脑后动脉梗塞29ppt课件Durette hemorrhage 30ppt课件Dur

13、ette hemorrhage31ppt课件Kernohans notch颞叶疝压迹32ppt课件Uncal herniationnWhen mass effects within or adjacent to the temporal lobe occur,the medial portion of the temporal lobe(uncus)is forced medially and downward over the tentorium.There is ipsilateral pupillary dilation.The uncus is pushed medially into

14、 the suprasellar cistern.There is bilateral uncal herniation.The suprasellar cistern is obliterated.33ppt课件early uncal herniation nThe right uncus is pushing into the suprasellar cistern;early right uncal herniation.34ppt课件中心疝35ppt课件中心疝36ppt课件Superior vermian herniation(ascending transtentorial hern

15、iation)n由于后颅凹的占位效应，小脑蚓和小脑半球通过小脑幕切迹向上移动37ppt课件陀螺状外观38ppt课件双侧环池变窄39ppt课件四叠体池充满40ppt课件不露齿的微笑41ppt课件皱眉42ppt课件第一天的四叠体池和环池43ppt课件第二天，四叠体池和环池消失44ppt课件脑积水45ppt课件ascending transtentorial herniation46ppt课件枕大孔疝47ppt课件枕大孔疝48ppt课件Tonsillar herniation nIn tonsillar herniation(rare),a mass effect in the posterior

16、fossa causes the cerebellar tonsils to herniate inferiorly through the foramen magnum compressing the medulla and upper cervical spinal cord.Conscious patients complain of neck pain and vomiting.They may have nystagmus,pupillary dilatation,bradycardia,hypertension and respiratory depression.Early to

17、nsillar herniation is difficult to recognize in an unconscious patient.It may not be evident on CT scan since axial views cannot see the pathology well.It is best seen on sagittal MRI.Clinically changes in vital signs may be the only clinical clue in an unconscious patient.49ppt课件Tonsillar herniatio

18、n50ppt课件a male patient in his 30s who died of brain stem herniation after completing a marathon.nThe CT shows(A)loss of the rostral cerebral sulci suggesting increase in ICP,(B)and(C)a large hydrocephalus with widening of both temporal horns.The grey matter can still be differentiated from the white

19、 matter,but all sulci are lost.This suggests that the brain oedema is of relative recent onset and massive tissue ischaemia has not yet occurred.(D)Compression of the fourth ventricle with dilatation of the third ventricle and the caudal aspect of both temporal horns.This is observed with considerab

20、le brain oedema and obstructive hydrocephalus.(E)Herniation of the medulla and pons into the foramen magnum.(F)The tonsils are located at the level of the dens which is a good indicator for foramen magnum herniation.51ppt课件n(A)The disc shows florid hemorrhages with relatively little swelling,indicat

21、ing a rapid,dramatic increase in CSF pressure.Progressive changes of optic disc oedema are seen in a patient with an intracranial tumour who declined treatment(B-D).(B)Early nerve fiber dilatation is seen particularly superiorly,inferiorly and nasally.(C)This increases and venous engorgement develop

22、s.(D)Temporal nerve fiber dilatation and swelling of the disc increases and hemorrhages appear.(E)In gross chronic disc oedema the normal retinal vasculature is masked and dilated superficial capillaries are observed.(F)In atrophic optic disc oedema nerve fibers are eventually destroyed and the opti

23、c disc without viable nerve fibers does not swell.This patient had longstanding benign intracranial hypertension.Retinochoroidal venous collaterals are present(black arrowhead).52ppt课件颅外疝53ppt课件核磁选择n1.Subfalcine herniation.This is best seen on coronal MR images.n2.Descending transtentorial herniatio

24、n(uncal herniation,hippocampal herniation).best seen on coronal images,but the compression of the brainstem is best observed on axial T2-WI.n3.Ascending transtentorial herniation.The sagittal imaging plane is preferred.n4.Cerebellar tonsillar herniation.Sagittal and coronal imaging planes are preferred.54ppt课件55ppt课件56ppt课件小结n占位效应引起的脑组织移位n影像上识别脑疝的关键是看脑池的变化57ppt课件