Ⅰ型无脑回畸形是一种严重的脑部畸形,因神经元迁移至新大脑皮层受阻所致。镜下可见脑沟部分或完全缺如,常见无脑回与巨脑回并存,临床表现为严重的发育迟缓、癫痫及小头畸形。Miller-Dieker综合征(MDS)的特征是1或2级无脑回(缺脑回或完全无脑回),以及特异的面部表现:双颞凹陷、前额突出、鼻短伴鼻孔上翻、上 Type I atrophy is a severe deformity of the brain caused by obstruction of neuronal migration to the neocortex. Microscopically visible part of the sulci or completely missing, the common anencephaly and the giant brain back coexist, the clinical manifestations of severe retardation, epilepsy and microcephaly. The characteristics of the Miller-Dieker syndrome (MDS) are grade 1 or 2 anencephaly (lack of or without a brain back), as well as specific facial features: bilateral temporal recess, prominent forehead, short nasal constriction,