Fetal Neural Axis

2. Most severe form of holoprosencephaly characterized by a single common ventricle and a malformed brain
4. Closed defect of the spine without protrusion of meninges or spinal cord
7. Open spinal defect characterized by protrusion of the spinal meninges
8. Enlargement of the fetal cranium as a result of ventriculomegaly
9. Form of holoprosencephaly characterized by a common ventricle, hypotelorism, and a nose with a single nostril
11. Severe form of holoprosencephaly characterized by a common ventricle, fusion of the orbits with one or two eyes present, and a proboscis
12. Open spinal defect characterized by protrusion of meninges and spinal cord through the defect, usually within a meningeal sac
13. An abnormality or congenital malformation
14. Congenital absence of the cerebral hemispheres caused by occlusion of the carotid arteries; midbrain structures are present, and fluid replaces cerebral tissue
15. Neural tube defect of the spine in which the dorsal vertebrae fail to fuse together, allowing the protrusion of meninges and/or spinal cord through the defect

1. Abnormal accumulation of cerebrospinal fluid within the cerebral ventricles leading to dilatation of the ventricles; compression of developing brain tissue and brain damage may result; commonly associated with additional fetal anomalies
3. Increase in size of the jugular lymphatic sacs caused by abnormal development
5. Neural tube defect characterized by lack of development of the cerebral and cerebellar hemispheres and cranial vault; this abnormality is incompatible with life
6. Ventriculomegaly in the neonate; abnormal accumulation of cerebrospinal fluid within the cerebral ventricles resulting in compression and, frequently, destruction of brain tissue
10. Range of abnormalities resulting from abnormal cleavage of the forebrain
13. Condition associated with anencephaly in which there is complete or partial absence of the cranial bones