图3-1 小脑上、中、下脚 解剖图正中矢状面观(a)和MRI(T1WI)矢状位(b、c) 1.小脑上脚(Superior cerebellar peduncle) 12.四脑室(Fourth ventricle) 2.小脑(Cerebellum) 13.扣带回峡(Isthmus of cingulate gyrus) 3.脑桥(Pons) 14.下丘(Inferior colliculus) 4.松果体(Pineal body) 15.尾状核头(Head of caudate nucleus) 5.四叠体(Quadrigeminal body) 16.视束(Optic tract) 6.中脑(Midbrain) 17.延髓(Medulla oblongata) 7.丘脑(Thalamus) 18.动眼神经(Oculomotor nerve) 8.后连合(Posterior commissure) 19.后交通动脉(Posterior communicating artery) 9.乳头体(Mammillary body) 20.壳(Putamen) 10.胼胝体压部(Splenium of corpus callosum) 21.小脑下脚(Inferior cerebellar peduncle) 11.三脑室脉络丛(Choroid plexus of third ventricle) 22.小脑中脚(Middle cerebellar peduncle) 图3-2 小脑上、中、下脚 MRI(T1WI)横轴位(由上至下的连续切面)(a-c) 1.小脑上脚(Superior cerebellar peduncle) 10.小脑半球(Cerebellar hemisphere) 2.脑桥网状结构(Reticular formation) 11.桥池(Pontine cistern) 3.蓝斑(Locus ceruleus) 12.脑桥(Pons) 4.第四脑室(Fourth ventricle) 13.小脑中脚(Middle cerebellar peduncle) 5.小舌(Lingula) 14.小结(Nodule) 6.环池(Cisterna ambiens) 15.齿状核(Dentate nucleus) 7.小脑蚓(Vermis) 16.小脑下脚(Inferior cerebellar peduncle) 8.杏仁体(Amygdaloid body) 17.延髓(Medulla oblongata) 9.垂体(Hypophysis) 18.蚓垂(Uvula of vermis) 图3-3 小脑上、中、下脚 MRI(T1WI)冠状位(a)、3D重建图(b) 1.小脑上脚(Superior cerebellar peduncle) 2.第四脑室(Fourth ventricle) 3.胼胝体干(Trunk of corpus callosum) 4.小脑下脚(Inferior cerebellar peduncle) 5.小脑半球(Cerebellar hemisphere) 6.下丘(Inferior colliculus) 7.小脑中脚(Middle cerebellar peduncle) 注:小脑上脚又称结合臂,连接小脑、中脑和间脑,两侧小脑上脚构成第四脑室顶部外侧壁,小脑中脚又称脑桥臂,位于最外侧,连接小脑和脑桥,小脑下脚又称绳状体,连接小脑、延髓和脊髓。在菱形窝下角,有第四脑室脉络丛带附着的弯曲边缘,称闩,它是表示切面水平的常用标志 图3-4 小脑蚓部及脑叶结构 MRI(T1WI)显示小脑蚓部的正中矢状位(a)和解剖图正中矢状面观(b) 1.小舌(Lingula) 11.水平裂(Horizontal fissure) 2.中央小叶(Central lobule) 12.次裂(Secondary fissure) 3.山顶(Culmen) 13.后外侧裂(Posterolateral fissure) 4.山坡(Declive) 14.小脑扁桃体(Tonsil of cerebellum) 5.蚓叶(Vermiform lobe) 15.二腹小叶(Biventral lobule) 6.蚓结节(Tuber of vermis) 16.薄小叶(Gracile lobule) 7.蚓锥体(Pyramid of vermis) 17.下半月小叶(Inferior semilunar lobule) 8.蚓垂(Uvula of vermis) 18.上半月小叶(Superior semilunar lobule) 9.小结(Nodule) 19.中央白质(Central white matter) 10.原裂(Primary fissure) 20.第四脑室(Fourth ventricle) 注:小脑两侧膨大,为小脑半球;中间部狭窄,为小脑蚓。小脑蚓上缘略高于小脑半球。上面观可见小脑半球的上表面和小脑上蚓:上蚓被深沟分为5部分,从前到后依次为小舌、中央小叶、山顶、山坡和蚓叶。下面观可见位于中间的小脑下蚓深陷于两半球之间,从前向后依次为小结、蚓垂、蚓锥体和蚓结节 图3-5 小脑脑叶结构 MRI(T1WI)显示小脑上脚的旁正中矢状位(a)和显示小脑中脚的旁正中矢状位(b) 1.中央小叶(Central lobule) 10.水平裂(Horizontal fissure) 2.方形小叶前部(Anterior quadrangular lobule) 11.次裂(Secondary fissure) 3.方形小叶后部(Posterior quadrangular lobule) 12.第四脑室(Fourth ventricle) 4.上半月小叶(Superior semilunar lobule) 13.小脑上脚(Inferior cerebellar peduncle) 5.下半月小叶(Inferior semilunar lobule) 14.下丘(Inferior colliculus) 6.薄小叶(Gracile lobule) 15.上后裂(Superior posterior fissure) 7.二腹小叶(Biventral lobule) 16.小脑中脚(Middle cerebellar peduncle) 8.小脑扁桃体(Tonsil of cerebellum) 17.齿状核(Dentate nucleus) 9.原裂(Primary fissure) 18.延髓(Medulla oblongata) 注:小脑位于后颅窝,呈楔形,被小脑幕覆盖,由两侧小脑半球和中线连接部的蚓部组成。小脑的上方以小脑前切迹为界,后下方伸入枕区。小脑上蚓除小舌外每个小叶向两侧都与相应的半球的小叶相连:山坡和山顶连于方形小叶,中间隔以原裂;蚓叶连于上半月小叶,后方以水平裂与下半月小叶相接;蚓结节向两侧连于下半月小叶;蚓锥体连于二腹小叶;蚓垂连于小脑扁桃体,二者之间隔以次裂 图3-6 小脑脑叶结构 MRI(T1WI)冠状位(a)和解剖图下面观(b) 1.山顶(Culmen) 9.绒球(Flocculus) 2.方形小叶前部(Anterior quadrangular lobule) 10.延髓(Medulla oblongata) 3.方形小叶后部(Posterior quadrangular lobule) 11.蚓锥体(Pyramid of vermis) 4.上半月小叶(Superior semilunar lobule) 12.蚓结节(Tuber of vermis) 5.下半月小叶(Inferior semilunar lobule) 13.次裂(Secondary fissure) 6.二腹小叶(Biventral lobule) 14.薄小叶(Gracile lobule) 7.蚓垂(Uvula of vermis) 15.小结(Nodule) 8.小脑扁桃体(Tonsil of cerebellum) 16.原裂(Primary fissure) 注:二腹小叶和小脑扁桃体两者合称为正中旁小叶;上半月小叶、下半月小叶及二腹小叶也称为袢状小叶。方形小叶前部相当于山顶,方形小叶后部相当于山坡,上半月小叶相当于蚓叶,下半月小叶相当于蚓结节。绒球是小脑结构中游离的一小部分,位于桥小脑脚池内,与前庭蜗神经紧邻。舌咽、迷走神经穿越绒球前部走向颈静脉孔 图3-7 小脑脑叶结构 MRI(T1WI)冠状位(由前至后的连续切面)(a-c) 1.环池(Cisterna ambiens) 12.距状沟(Calcarine sulcus) 2.小结(Nodule) 13.蚓锥体(Pyramid of vermis) 3.侧脑室后角(Posterior horn of lateral ventricle) 14.山顶(Culmen) 4.齿状核(Dentate nucleus) 15.上后裂(Superior posterior fissure) 5.方形小叶前部(Anterior quadrangular lobule) 16.水平裂(Horizontal fissure) 6.方形小叶后部(Posterior quadrangular lobule) 17.枕叶(Occipital lobe) 7.上半月小叶(Superior semilunar lobule) 18.山坡(Declive) 8.小脑白质(Cerebellar medulla) 19.蚓结节(Tuber of vermis) 9.下半月小叶(Inferior semilunar lobule) 20.小脑延髓池(Cerebellomedullary cistern) 10.小脑扁桃体(Tonsil of cerebellum) 21.原裂(Primary fissure) 11.二腹小叶(Biventral lobule) 注:原裂将小脑分为前叶和后叶,前叶包括小舌、中央小叶、山顶和方形小叶前部,后叶分为中叶和固有后叶,中叶包括山坡、蚓结节、方形小叶后部、上半月小叶、下半月小叶,固有后叶的半球部和蚓部分别包括二腹小叶、小脑扁桃体和蚓锥体、蚓垂。水平裂将上半月小叶和下半月小叶分隔 图3-8 小脑结构 3D重建图 1.山坡(Declive) 2.方形小叶后部(Posterior quadrangular lobule) 3.上半月小叶(Superior semilunar lobule) 4.下半月小叶(Inferior semilunar lobule) 5.蚓结节(Tuber of vermis) 6.小脑扁桃体(Tonsil of cerebellum) 7.二腹小叶(Biventral lobule) 8.延髓(Medulla oblongata) 9.水平裂(Horizontal fissure) 10.大脑纵裂(Cerebral longitudinal fissure) 11.外侧沟(Lateral sulcus) 12.颞上回(Superior temporal gyrus) 13.颞上沟(Superior temporal sulcus) 14.距状沟(Calcarine sulcus) 图3-9 小脑结构 3D重建图 1.齿状核(Dentate nucleus) 2.下半月小叶(Inferior semilunar lobule) 3.二腹小叶(Biventral lobule) 4.小脑扁桃体(Tonsil of cerebellum) 5.次裂(Secondary fissure) 6.水平裂(Horizontal fissure) 7.大脑纵裂(Cerebral longitudinal fissure) 8.延髓(Medulla oblongata) 9.距状沟(Calcarine sulcus) 10.顶枕沟(Parietooccipital sulcus) 11.丘脑(Thalamus) 12.尾状核(Caudate nucleus) |
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