1、图解脑疝医学知识宣讲图解脑疝医学知识宣讲脑疝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。图解脑疝医学知识宣讲2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：脑组织通过颅外缺损疝出。ne.
2、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。图解脑疝医学知识宣讲3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 transtentorial h
3、erniation(reversed tentorial)上行性小脑幕疝ng)sphenoid herniation蝶骨嵴疝图解脑疝医学知识宣讲4类型脑疝部位命名别名疝入脑组织命名1大脑镰下疝扣带回疝2小脑天幕疝 前疝 后疝小脑幕切迹疝、小脑幕下降疝脚间池疝环池疝，四叠体疝颞叶钩回疝海马回疝3小脑幕孔中心疝间脑 4小脑幕孔上疝小脑幕上疝 小脑蚓部疝 5枕骨大孔疝小脑扁桃体疝 图解脑疝医学知识宣讲5示意图图解脑疝医学知识宣讲6解剖关系图解脑疝医学知识宣讲7解剖关系FQcMb3vTOSyCClvFPOSpCClvss图解脑疝医学知识宣讲8解剖关系FTCesPd4th VFTMbCes图解脑疝医学知
4、识宣讲9The suprasellar cistern&the quadrigeminal cisternnThe left and center images show the suprasellar cistern.Its anterior borders are formed 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 suprasel
5、lar cistern where the posterior border is formed by the pons(Po).The black arrow points to the fourth ventricle.The center image shows a 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 clef
6、t.nThe right image shows the quadrigeminal cistern(black arrow).Note the babys bottom appearance of its anterior border.When ICP is increased,the quadrigeminal cistern space is compressed or obliterated.图解脑疝医学知识宣讲10The suprasellar cistern&the quadrigeminal cistern.nThe midline sagittal MRI scan show
7、s the levels of the axial diagrams.The quadrigeminal cistern is located above(anterior to)the Q in the highest cut shown(number 9).The anterior 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
8、border is formed by the inferior colliculi(c).This gives the anterior border of the quadrigeminal cistern the appearance of a babys bottom.The quadrigeminal plate is comprised of the superior and inferior colliculi.The quadrigeminal cistern is posterior to this quadrigeminal plate,thus its anterior
9、border may be formed by the inferior or superior colliculi.图解脑疝医学知识宣讲11镰下疝临床表现影像所见并发症头痛对侧下肢无力同侧额角截断大脑镰前份不对称同侧侧脑室腔消失透明隔移位因大脑前动脉卡压到大脑镰上引起同侧ACA供血区梗塞伴有其他疝图解脑疝医学知识宣讲12Subfalcine herniation(cingulate herniation)Transtentorial herniation nThe suprasellar cistern(left image)is obliterated.The quadrigeminal
10、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.图解脑疝医学知识宣讲13ACA供血区梗塞图解脑疝医学知识宣讲14Uncal herniation临床表现影像所见并发症同侧瞳孔散大、眼动受限（动眼神经受压）对侧偏瘫（同侧大脑脚受压）有时颞叶疝压迹会导致同侧偏瘫（对侧大脑脚受压。假定位体征）对侧颞角增宽同
11、侧环池增宽同侧桥前池增宽钩回进入鞍上池大脑后动脉受压导致枕叶梗塞图解脑疝医学知识宣讲15鞍上池缺角图解脑疝医学知识宣讲16冠状位CT与MRI图解脑疝医学知识宣讲17海马旁回褶皱图解脑疝医学知识宣讲18对侧颞角增宽图解脑疝医学知识宣讲19同侧桥前池增宽图解脑疝医学知识宣讲20同侧环池增宽图解脑疝医学知识宣讲21Uncal herniation图解脑疝医学知识宣讲22Uncal herniationnobliteration of the suprasellar cistern(red arrow)and the quadrigeminal cistern(green arrow)图解脑疝医学知识
12、宣讲23Uncal herniationnThe ipsilateral ventricle,sulci,fissures are compressed and obliterated,isappeared.nobliteration of the suprasellar cistern(s)and quadrigeminal cistern(q)图解脑疝医学知识宣讲24Uncal herniationnAcute infarctionn1st daynAcute infarction n4th daysq图解脑疝医学知识宣讲25Uncal herniationnBefore surgery,
13、a big GBM in the left temporal lobe with uncal herniation.nAfter surgery,the GBM was removed,the suprasellar cistern and quadrigeminal cisterns are normal.图解脑疝医学知识宣讲26Uncal herniationnAcute infarction of right posterior artery(PCA),this is a complication of uncal/transtentorial herniation,because th
14、e PCA was compressed by brain herniation.图解脑疝医学知识宣讲27双侧大脑后动脉梗塞图解脑疝医学知识宣讲28双侧大脑后动脉梗塞图解脑疝医学知识宣讲29Durette hemorrhage 图解脑疝医学知识宣讲30Durette hemorrhage图解脑疝医学知识宣讲31Kernohans notch颞叶疝压迹图解脑疝医学知识宣讲32Uncal herniationnWhen mass effects within or adjacent to the temporal lobe occur,the medial portion of the tempo
15、ral lobe(uncus)is forced medially and downward over the tentorium.There is ipsilateral pupillary dilation.The uncus is pushed medially into the suprasellar cistern.There is bilateral uncal herniation.The suprasellar cistern is obliterated.图解脑疝医学知识宣讲33early uncal herniation nThe right uncus is pushin
16、g into the suprasellar cistern;early right uncal herniation.图解脑疝医学知识宣讲34中心疝临床表现影像所见并发症意识改变呼吸模式改变去皮层、去脑小瞳孔因脉络膜前动脉受压引起苍白球和视束梗塞图解脑疝医学知识宣讲35中心疝图解脑疝医学知识宣讲36Superior vermian herniation(ascending transtentorial herniation)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临床表现影像所见并发症恶心呕吐意识障碍中脑外观呈陀螺状双侧环池变窄四叠体池充满因小脑上动脉受压引起梗塞Gal
17、en静脉移位脑积水意识障碍迅速出现，并可能死亡图解脑疝医学知识宣讲37陀螺状外观图解脑疝医学知识宣讲38双侧环池变窄图解脑疝医学知识宣讲39四叠体池充满图解脑疝医学知识宣讲40不露齿的微笑图解脑疝医学知识宣讲41皱眉图解脑疝医学知识宣讲42第二天，四叠体池和环池消失图解脑疝医学知识宣讲44脑积水图解脑疝医学知识宣讲45ascending transtentorial herniation图解脑疝医学知识宣讲46枕大孔疝临床表现影像所见并发症双侧上肢感觉减退意识障碍轴位像见到小脑扁桃体位于齿状突水平矢状位见到小脑扁桃体低于枕大孔5mm（成人）或7mm（儿童）小脑扁桃体出血性坏死意识障碍和死亡图解
18、脑疝医学知识宣讲47枕大孔疝图解脑疝医学知识宣讲48Tonsillar herniation nIn tonsillar herniation(rare),a mass effect in the posterior 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 vomit
19、ing.They may have nystagmus,pupillary dilatation,bradycardia,hypertension and respiratory depression.Early tonsillar 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.Clinica
20、lly changes in vital signs may be the only clinical clue in an unconscious patient.图解脑疝医学知识宣讲49Tonsillar herniation图解脑疝医学知识宣讲50a 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(
21、C)a large hydrocephalus with widening of both temporal horns.The grey matter can still be differentiated from the white 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 ventric
22、le with dilatation of the third ventricle and the caudal aspect of both temporal horns.This is observed with considerable 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 indic
23、ator for foramen magnum herniation.图解脑疝医学知识宣讲51n(A)The disc shows florid hemorrhages with relatively little swelling,indicating 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 ne
24、rve fiber dilatation is seen particularly superiorly,inferiorly and nasally.(C)This increases and venous engorgement develops.(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 dila
25、ted superficial capillaries are observed.(F)In atrophic optic disc oedema nerve fibers are eventually destroyed and the optic disc without viable nerve fibers does not swell.This patient had longstanding benign intracranial hypertension.Retinochoroidal venous collaterals are present(black arrowhead)
26、.图解脑疝医学知识宣讲52颅外疝图解脑疝医学知识宣讲53核磁选择n1.Subfalcine herniation.This is best seen on coronal MR images.n2.Descending transtentorial herniation(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.图解脑疝医学知识宣讲54图解脑疝医学知识宣讲55图解脑疝医学知识宣讲56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图解脑疝医学知识宣讲57
