Ｃｈｉａｒｉ畸形包括一组后颅窝解剖缺损性疾病，从小脑组织的轻微移位到严重的骨质缺损或小脑发育不良。Ｃｈｉａｒｉ畸形分为四种类型［１］：Ⅰ型：小脑扁桃体突入到颈段椎管内，无明显脑干移位。小脑中线结构无延长，上颈支在出椎管前向尾侧走行。Ⅱ型：小脑蚓部延长... Chiari malformations include a set of posterior fossa anatomic defects, ranging from a slight shift of cerebellar tissue to severe bone defects or cerebellar dysplasia. Chiari deformity is divided into four types [1]: Type I: cerebellar tonsillar protrusion into the cervical spinal canal, no significant brain stem shift. No extension of the structure of the cerebellum midline, the upper cervical branch in the spinal canal to the caudal before walking. Type II: cerebellar vermis extended ...