Developmental Anomalies Flashcards
What are the cells of the neural plate that develop into the PNS?
Neural crest cells
What are the cells of the neural plate that develop into the CNS?
Cells from the wall of the neural tube
What are the cells of the neural plate that develop into the ventricles and spinal canal?
Lumen of the neural tube
Neural tube defects are associated with what vitamin deficiency? When in development is supplementation needed?
Folate–needed prior to conception
How do you monitor for neural tube defects in utero?
Elevated AFP in amniotic and maternal blood
What is anencephaly?
Failure of the neural tube to close at the cranial end
What is the classic appearance of an anencephalic neonate?
“Frog-like” appearance, with an absence of a skull and brain
What is the effect of anencephaly on amniotic fluid levels? Why?
Polyhydramnios–absence of brain leads to absence of swallow reflex
What is spina bifida occulta?
Dimple or patch of hair overlying the vertebral defect
What is spina bifida with meningocele?
Meninges herniate through a neural tube defect
What is spina bifida with meningomyelocele?
Meninges and spinal cord herniate through a neural tube defect
What is congenital aqueduct stenosis?
Stenosis of the channel that drains the CSF from the 3rd and 4th ventricles, leading to accumulation of CSF in the ventricle
What is the presentation of cerebral aqueduct stenosis? Why?
Enlarging head circumference d/t inability to drain CSF from the 3rd and 4th ventricles
What is the body in the ventricles that makes CSF?
Choroid plexus
What is the flow of CSF from the lateral ventricles, to the 4th?
- Lateral
- Foramen of monroe
- Third ventricle
- Cerebral aqueduct
What is the connection between the lateral ventricle and the third ventricle?
Foramen of monro
What is the connection between the third ventricle and the fourth??
Cerebral aqueduct
What is Dandy Walker malformation? How does it present?
- Congenital failure of the cerebellar vermis to develop
- Massively dilated 4th ventricle with an absent cerebellum
What are the characteristic findings of Dandy-walker malformation on imaging?
-Massively dilated 4th ventricle with an absent cerebellum; often accompanied by hydrocephalus
What is Arnold-Chiari malformation?
Congenital extension of the cerebellar tonsils through the foramen magnum
What are the two conditions that may present with Arnold-Chiari malformations?
- Meningomyelocele
- Syringomyelia
What is one of the sequelae of Arnold-Chiari malformation?
Hydrocephalus d/t CSF flow obstruction
