Neuro Embryology EC Flashcards Preview

Evan's Step 1 Prep Material > Neuro Embryology EC > Flashcards

Flashcards in Neuro Embryology EC Deck (18):
1

Describe the development of the neural tube

Notochord induces overlying ectoderm to differentiate into neuroectoderm and form the neural plate
Neural plate gives rise to the neural tube and neural crest cells
Notochord becomes nucleus pulposus of the intervertebral disc in adults

2

What are the Alar and Basal plates?

Alar plate=Dorsal/Sensory
Basal plate=Ventral/Motor

3

What are the three primary vesicles of the developing brain?

Prosencephalon (forebrain)
Mesencephalon (midbrain)
Rhombencephalon (hindbrain)

4

To what structures does the prosencephalon give rise?

Telencephalon --> Cerebral hemispheres/Lateral ventricles

Diencephalon --> Thalamus/Third ventricle

5

To what structures does the mesencephalon give rise?

Mesencephalon--> Midbrain/Cerebral aqueduct

6

To what structures does the rhombencephalon give rise?

Metencephalon--> Pons and Cerebellum/upper 4th ventricle

Myelencephalon--> Medulla/lower 4th ventricle

7

What is the mechanism of neural tube defects?

Neuropores fail to fuse (4th week) --> persistent connection between amniotic cavity and spinal canal.

8

Failure of bony spinal canal to close but no structural herniation. Seen at lower vertebral levels. Dura intact and tuft of hair or skin dimple observed at level of bony defect.

Spina bifida occulta

9

Meninges (but not spinal cord) herniate through spinal canal defect

Meningocele

10

Meninges and spinal cord herniate through spinal canal defect

Meningomyelocele

11

Malformation of anterior neural tube resulting in no forebrain, open calvarium (frog-like appearance). Clinical findings: Increased AFP, polyhydramnios,

Anencephaly

Associated with maternal diabetes
Maternal folate supplementation decreases risk

12

Failure of left and right hemispheres to separate; usually occurs during weeks 5-6. Complex multifactorial etiology that may be related to Shh pathway. Moderate form has cleft lip/palate, most severe form results in cyclopia.

Holoprosencephaly

13

Significant cerebellar tonsillar and vermian herniation through foramen magnum with aqueductal stenosis and hydrocephalus. Often presents with thoraco-lumbar myelomeningocele and paralysis below defect.

Chiari II malformation

14

Agenesis of cerebellar vermis with cystic enlargement of 4th ventricle. Associated with hydrocephalus and spina bifida

Dandy-Walker malformation

15

Cystic enlargement of central canal of spinal cord. Results in "cape-like" bilateral loss of P/T in upper extremities (fine touch preserved).

Syringomyelia

Associated with Chiari I

16

Taste and sensation in anterior 2/3 of tongue

VII taste
V3 sensation

17

Taste and sensation in posterior 1/3 of tongue

IX

18

Taste and sensation of palate/extreme posterior tongue

X

Decks in Evan's Step 1 Prep Material Class (72):