医学脑疝分类及影像学表现图解 北京天坛医院神经内科 杜万良课件.ppt

图解脑疝 北京天坛医院神经内科 杜万良（reflexhammer） 脑疝 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。 脑疝的类型： a.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。 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；②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。 c.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。 d.颅外疝： 脑组织通过颅外缺损疝出。 e.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。 g.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。 示意图 a) subfalcial (cingulate) herniation ;镰下疝 b) uncal herniation ; 钩疝 c) downward (central, transtentorial) herniation ; 下行性小脑幕疝 d) external herniation ; 颅外疝 e) tonsillar herniation.扁桃体疝 f) ascending transtentorial herniation (reversed tentorial)上行性小脑幕疝 g) sphenoid herniation蝶骨嵴疝 类型 示意图 解剖关系 解剖关系 解剖关系 The suprasellar cistern the quadrigeminal cistern The 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 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 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. The 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. The suprasellar cistern the quadrigeminal cistern. The 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 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 border is formed by the inferior colliculi (c). This gives the anterior bor