n.无脑畸形
Anencephaly is absence of the fetal cranial vault. 无脑儿是胎儿颅穹窿缺陷。
The absence of the fetal cranial vault in anencephaly is shown here. 无脑儿显示胎儿颅穹窿缺陷。
The rate of anencephaly is now less than 1 in 10,000 live births in some places. 目前在一些地方新生无脑儿发病率低于1/10000。
The highest of neural tube defects is spina bifida,then is anencephaly encephalocele,and so on. 发生率最高的神经管畸形是脊柱裂,其他依次为无脑畸形、脑膨出、小头畸形。
Although the rate of anencephaly decreased 36% from 1991 to 1995, it did not change significantly from 1995 to 2005. 无脑症比率从1991至1995年减少36%25，1995至2005年间则无显著改变。
