Neuro Exam 1: Basic Path

Front 1

What are the major cell populations in the CNS?

Back 1

1. Neurons
2. Oligodendrocytes and their myelin sheaths
3. Astrocytes

Front 2

What two cell types make up the glial cells?

Back 2

oligodendrocytes and astrocytes

Front 3

Where are the glial cells located (white or grey)?

Back 3

grey matter

Front 4

What composes the white matter of the brain?

Back 4

axonal processes of the neurons and glial cells (astros and oligos)

Front 5

what type of cells have perinuclear clearing?

Back 5

oligodendrocytes

Front 6

what cells line the ventricals?

Back 6

columnar/cuboidal, ciliated EPENDYMAL cells

Front 7

What produces CSF?

Back 7

choroid plexus in lateral, 3rd and 4th ventricles

Front 8

What are the leptomeninges?

Back 8

arachnoid + pia (covering of outer surface of brain)

Front 9

In what space is the CSF located?

Back 9

subarachnoid (b/w arachnoid and pia)

Front 10

What is the brain correlate of fibroblasts?

Back 10

astrocytes

Front 11

What is Wallerian degeneration?

Back 11

degeneration of an axon distal to an injury

Front 12

Walk through neuron injury in the CNS.

Back 12

1. distal axon degenerates
2. 2'ary myelin degeneration
3. macrophages come in and eat up myelin
4. astrocytes proliferate (reactive gliosis) and produce lots of INTRACELLULAR glial filaments which form glial scar
5. proximal neuron is non-functional

Front 13

At what level is the BBB?

Back 13

brain capillary

Front 14

Which types of drugs easily cross the BBB?

Back 14

lipid soluble

Front 15

What controls the extracellular environment of the brain?

Back 15

BBB

Front 16

What things cause BBB breakdown?

Back 16

inflammation, tumors, trauma, infarcts, etc. (anything that causes leaky blood vessels)

Front 17

Why do tumors breakdown the BBB?

Back 17

b/c tumors make their own (leaky) capillaries

Front 18

How does breakdown of the BBB lead to extracellular edema?

Back 18

leakage of proteins into extracellular space draws water.

Front 19

White or Grey: more extracellular edema

Back 19

White

Front 20

What is vasogenic brain edema?

Back 20

extracellular edema due to increased permeability of brain caps (breakdown of BBB, white matter)

Front 21

What is cytotoxic brain edema?

Back 21

intracellular edema from osmotic imbalance (grey matter)

Front 22

define hydrocephalus

Back 22

enlargement of ventricles due to obstruction of the bulk flow of CSF

Front 23

What is noncommunicating hydrocephalus?

Back 23

obstruction w/in the ventricular system (aqueductal stenosis)

Front 24

What is communicating hydrocephalus?

Back 24

obstruction w/in the subarachnoid space or arachnoid villi

Front 25

what is hydrocephalus ex vacuo?

Back 25

ventriculomegaly from loss of brain tissue (atrophy)

Front 26

What is a Dandy-Walker malformation?

Back 26

hindbrain malformation defined by the triad of:
1. hypoplasia of the cerebellar vermis
2. cystic dilitation of 4th ventricle
3. enlargement of posterior fossa

Front 27

What is a Chiari II malformation (Arnold-Chiari malformation)?

Back 27

hindbrain malformation that is closely assoc w/ meningiomyelocele

Front 28

What is the cerebral perfusion pressure (CPP)?

Back 28

MAP - ICP

Front 29

What are clinical signs of increased ICP?

Back 29

HA, N/V, papiledema

Front 30

Give some causes of increased ICP

Back 30

1. Mass lesion
2. Hydrocephalus
3. Diffuse brain edema
4. Obstruction of major dural sinus
5. Ididopathic (pseudotumor cerebri)

Front 31

What are some signs of left mass lesion in the brain?

Back 31

left-to-right subfalcine herniation (singulate gyrus crosses midline displaces falx cerebri)
transtentorial herniation of the temporal lobe (uncal going down) or diencephalon (central herniation)
tonsillar herniation

Front 32

What are the sx of uncal herniation syndrome?

Back 32

dilated ipsilateral pupil
contralateral hemiplegia
coma, dilated pupils, abnormal respirations, etc.

Front 33

Again, what are the two major consequences of intracranial mass lesions?

Back 33

increased ICP and brain shifts w/ herniation

Front 34

How can you detect open NTD?

Back 34

elevated AFP in serum or amniotic fluid and by fetal U/S

Front 35

What is craniorachisisis totalis?

Back 35

failure of closure of the entire neural tube

Front 36

what is anencephaly?

Back 36

failure of neural tube closure limited to anterior neuropore

Front 37

What is an encephalocele?

Back 37

very restricted NTD (usually at base of skull)

Front 38

What is a myelomeningocele?

Back 38

failure of neural tube closure limited to region of posterior neuropore

Front 39

Are there neurologic deficits w/ a myelomeningocele?

Back 39

Yes!

Front 40

Are there neurologic deficits w/ a meningocele?

Back 40

No! Normal spinal cord and no deficits

Front 41

What is holoprosencephaly?

Back 41

failure of prosencephalon to divide the forebrain into two cerebral hemispheres

Front 42

Midline facial defects are associated with what defect?

Back 42

holoprosencephaly

Front 43

What is neuronal heterotopia?

Back 43

localized neuronal migration defect

Front 44

What are pacygyria (few wide gyri) and agyria (smooth brain) (lissencephaly) examples of?

Back 44

widespread neuronal migration defects

Front 45

What is polymicrogyria?

Back 45

too many gyri. caused by malformation or acquired process that leads to destruction of cortex