Etiology

 monogenic diseases
 chromosomal diseases
 inborn errors of metabolism
 exogenous causes

• teratogenic chemical agents
• teratogenic physical agents
• teratogenic infectious agents
• maternal diseases

Types

 neurulation failures

• faulty neural induction
• neural tube defects (dysraphia)

 failure of neural tube growth

• prosencephalon growth failure
  • holoprosencephaly
  • aprosencephaly
  • Corpus callosum agenesis
  • anomalies of the septum pellucidum
  • anomalies of the wall of the lateral ventricles

 brainstem and cerebellum growth failure

• brainstem anomalies
• cerebellar malformations

 cerebral cysts

• arachnoid cysts
• choroid plexus cysts
• subependymal pseudocysts

 cerebral vascular malformations

• cerebral arterioveinous malformations

 cytoarchitectonic anomalies

• neuronal heterotopias
• anomalies of the cortical plate
• agyria-pachygyria
  • lissencephaly
    • isolated lissencephaly
    • lissencephaly type 1-four layered-Miller-Dieker syndrome
    • lissencephaly type 2-cortical dysplasia-Walker-Warburg syndrome
    • lissencephaly type 3-micrencephaly-cytoarchitectonic anomalies

• microgyria
• polymicrogyria
• status verrucosus simplex

 microencepahly and micrencephaly
 megalencephaly
 congenital hydrocephalus

• obstructive hydrocephalus
• cerebral malformations associated hydrocephalus
• hydrocephalus with genetically transmitted disorders

See also:

 spinal cord malformations