10.25 CNS Development and Malformations

Question 1

the cavity of the diencephalon forms the __________

Answer 1

third ventricle

Question 2

what is the developmental origin of the PNS?

Answer 2

neural crest cells

Question 3

what are the three possible types of CNS abnormalities we went through in class?

Answer 3

neural tube defects
disorders of diverticulaltion
disorders of neural migration

Question 4

neuronal heterotopia is a disorder of ___________

Answer 4

migration

Question 5

what are the two secondary vesicles of the prosencephalon?

Answer 5

telencephalon

diencephalon

Question 6

white matter necrosis in periventricular areas

usually a result of anoxia in preemies

Answer 6

periventricular leukomalacia

Question 7

what does the diencephalon form? what primary vesicle did it originate from?

Answer 7

thalamus, hypothalamus, pineal gland, retina

prosencephalon

Question 8

holoprosencephaly is the failure of the ___________ to break into paired __________ vesicles

Answer 8

prosencephalon

telencephalic

Question 9

failure of vertebrae to close but the underlying spinal cord is normal.

Answer 9

spina bifida occulta

Question 10

failure of the rostral neural tube to close. Much of cerebral hemispheres does not develop.

Answer 10

anencephaly

Question 11

collections of neurons in what should be subcortical white matter

Answer 11

neuronal heterotopia

Question 12

smooth brain

Answer 12

lissencephaly

Question 13

failure of caudal neural tube to close, with cyst containing meninges only

Answer 13

spina bifida with meningocele

Question 14

♣ Displacement of cerebellar tonsils through foramen magnum
♣ Flattening of pons
♣ Beaking of tectum
♣ Hydrocephalus (CSF continues to be produced but can’t get out)

Answer 14

arnold-chiari malformation

Question 15

what is a disorder of diverticulation

Answer 15

holoprosencephaly

Question 16

sac like protrusions of brain and meninges through openings in skull. Cyst consisting of skin, dura, brain…. No skull.

Answer 16

encephalocele

Question 17

the cavity of the telencephalon forms the _________

Answer 17

4th ventricle

Question 18

failure of caudal neural tube to close. Vertebra fail to close over defect, forms cyst

Answer 18

spina bifida cystica

Question 19

failure of caudal neural tube to close, with cyst containing meninges and neural elements

Answer 19

spina bifida with meningomyelocele

Question 20

what are the three primary vesicles that bulge as the neural tube closes?

Answer 20

prosencephalon
mesencephalon
rhombencephalon

Question 21

what is Arnold-Chiari malformation usually associated with?

Answer 21

spina bifida with meningomyelocele

Question 22

what does the rhombencephalon become? it’s cavity becomes the ________ ventricle

Answer 22

pons, cerebellum, medulla

4th ventricle

Question 23

the alar plate eventually deals with __________ information while the basal plate eventually deals with _________ information

Answer 23

sensory

motor

Question 24

what does the telencephalon form? what primary vesicle did it originate from?

Answer 24

cerebral cortex, hippocampus, amygdala, chunks of basal ganglia
prosencephalon

Question 25

the ________________ is where cells proliferate (adjacent to lateral ventricle) and neurons and glia migrate out to cerebral cortex.

Answer 25

germinal matrix zone

Question 26

multiple small gyru

Answer 26

polymicrogyria

Question 27

what do neural crest cells form?

Answer 27

neurons and glia of the PNS

Question 28

alar plate is __________ to the sulcus limitans and the basal plate is _________ to the sulcus limitans

Answer 28

dorsal

motor

Question 29

lissencephaly is a disorder of __________

Answer 29

migration

Question 30

when the fourth ventricle begins to form (brainstem), the basal plate gets more _________ to the sulcus limitans and the alar plate gets more ________ to the sulcus limitans

Answer 30

medial

lateral

Question 31

periventricular leukomalacia usually involves ________________________ close to ventricles. what could you see?

Answer 31

motor command white matter tracts

bilateral paralysis and spasticity

Question 32

with respiratory distress syndrome, preemies can have hemorrhage in the ___________ __________ which can rupture into the ventricles and extent to subarachnoid space

Answer 32

germinal matrix

Question 33

failure of prosencephalon to break into paired telencephalic vesicles (AKA two hemispheres).

Answer 33

holoprosencephaly

Question 34

what are the 4 characteristics of Arnold-Chiara malformation

Answer 34

1. protrusion of cerebellar tonsils through foramen magnum
2. flattening of pons
3. beaking of tectum
4. hydrocephalus

Question 35

polymicrogyria is a disorder of __________

Answer 35

migration

Question 36

the mesencephalon forms the _________. it’s cavity becomes the ________

Answer 36

midbrain

aqueduct