S2 Neuro Exam 2: Csf & Ventricles

Front 1

Primary functions of the CSF

Back 1

-Provides mechanical buoyancy for the brain (shock absorber with arachnoid trabeculae)
-Removes waste (brain metabolites) and delivers some elements (O2 pressure, nutrients, some releasing hormones)
-Provides stable chemical environment for the CNS, isolating it from changes in the blood.

Front 2

What are the 4 ependyma-lined cavities w/i brain?

Back 2

right & left lateral ventricles (C-Shaped)
midline third (duck shaped) and fourth ventricle (pyrimidal shaped)

Front 3

The ventricles of the brain form as expansion of what?

Back 3

lumen of neural tube

Front 4

Where is CSF found?

Back 4

Subarachnoid Space & cerebral ventricles

Front 5

Each lateral ventricle is subdivided into 5 parts, name/describe them

Back 5

anterior horn- extends into frontal lobe
body- lies under corpus callosum & over thalmus
posterior horn- extends into occipital lobe
inferior horn- extends into temporal lobe
altrium- jxn of body, posterior horn, & inferior horn

Front 6

What Separates the Lateral Ventricles?

Back 6

Septum Pellucidum

Front 7

What does the septum pellucidum attach to?

Back 7

corpus callosum & fornix

Front 8

What are the walls of the 3rd ventricle formed by?

Back 8

the diencephalon

Front 9

Describe the 4 recesses associated w/ the 3rd ventricle

Back 9

1. The supraoptic recess above the optic chiasm
2. The infundibular recess (base of infundibulum)
3. The suprapineal recess (above the pineal gland)
4. The pineal recess (extends into pineal stalk)

Front 10

Where is CSF resorbed back into the Blood? Where are these found?

Back 10

-Arachnoid Villi or Granulations
-In the region of the Superior Sagittal Sinus, projecting through openings in the Dura

Front 11

What are Cisterns?

Back 11

-Large, CSF-Filled Pockets, natural expansions
-Where Brain and Skull are further apart

Front 12

What are the major subarachnoid Cisterns?

Back 12

-interpeduncular cistern
-quadrigeminal cistern
-Cisterna Magna/dorsal cerebellomedullary cistern (most clinically important) - Between Posterior Aspect of Cerebellum and Medulla
-prepontine cistern
-ambient cistern

Front 13

What does the Interventricular Foramen (of Monro) Connect?

Back 13

Lateral Ventricles to 3rd Ventricle

Front 14

What connects the 3rd and 4th Ventricles?

Back 14

Cerebral Aqueduct

Front 15

Describe the Flow of CSF.

Back 15

Lateral Ventricles
-Interventricular Foramen
-->3rd Ventricle
-Cerebral Aqueduct-->
-4th Ventricle
-Central Canal-->
-subarachnoid space

Front 16

How does CSF enter the Subarachnoid Space from the 4th ventricle? Where are these located?

Back 16

-Lateral Foramina of Luschka
-Median Foramina of Megendie
-In the walls of the 4th Ventricle

*only pathways out of ventricular system**

Front 17

How does CSF get back into blood circulation? Why doesn't it enter back into the Subarachnoid Space?

Back 17

-Subarachnoid Space has Arachnoid Granulations which is where it passes back
-Villi act as 1-way valves

Front 18

Why does CSF Flow in Direction it does?

Back 18

-Pressure Difference between its source (Arteries) and destination (Veins)
-Cilia on the Choroid Plexus also helps move it around

Front 19

What is the Choroid Plexus?

Back 19

-Clusters of Capillaries
-Hang from the Roof of the Ventricles
-formed from the outgrowth of tela choroidea***
*produces CSF

Front 20

In active CSF secretion what is actively transported into ventricles?

what comes in by diffusion?

Back 20

sodium & chloride


water & respiratory gases

Front 21

What are the stria medullares?

What do they end as?

Back 21

2 lateral recesses that extend out over surface of medulla from 4th ventricle

End as foramen of luschka

Front 22

What are the foramina of luschka?

Back 22

2 lateral openings from 4th ventricle that allow CSF to leave brain and enter meninges

Front 23

What is Hydrocephalus?

Back 23

An Increase in CSF Volume.


(leads to an increase in cranial pressure)

Front 24

What usually results during Hydrocephalus? Why?

Back 24

-Enlargement of the Ventricles
-Compression of the Brain
-Where the **** else is CSF gonna go?

Front 25

What Structure is just Lateral to the 3rd Ventricle?

Back 25

Thalamus

Front 26

What Structure is just Lateral to the Lateral Ventricles?

Back 26

Caudate

Front 27

What Structure is just Lateral to the 4th Ventricle?

Back 27

Hypothalamus

Front 28

What types of cells help circulate CSF?

Back 28

Ependymal Cells

*simple cuboidal epithelium lining surfaces of ventricles & spinal central canal
*have cilia to help move CSF

Front 29

What color is normal CSF?

What types of Cells are normally found in the CSF.

Back 29

clear & colorless

None

Front 30

If there is Protein in the CSF, what could cause this?

Back 30

Patients w/ primary CNS tumors usually have elevated protein levels in CSF

Front 31

What are the 2 biggest reasons for RBCs in the CSF?

Back 31

-Traumatic Spinal Tap (bloody lumbar punction
-Xanthorchromic - Yellow from Hemoglobin from Subarachnoid Bleed (may remain 2-4 wks)

Front 32

What could cause Intracranial Pressure to Increase?

Back 32

-Hydrocephalus - More CSF
-Mass Effect - Tumor, Hemorrhade, Abscesses
-Acute Brain Swelling, Edema

(considered >200 mm H20)

Front 33

What could Reduced Reabsorption of CSF cause? What are some other things that could cause this defect as well?

Back 33

Hydrocephalus
-Increased CSF Production
-Obstruction of CSF Flow
-Reduced Reabsorption
-Congenital Absence or Hypoplasia of Arachnoid Villi
-Cerebral Arophy

Front 34

What are some clinical symptoms of increased intracranial pressure?

Back 34

headache, changes in mental status with altered level of consciousness, nausea and vomiting, papilledema, forced downward gaze (setting sun sign; usually due to pressure on the midbrain) and seizures
(cushings triad- hypertension, bradycardia, irregular respiration)

Front 35

If there is Obstruction to CSF Flow within the Ventricular System, what is it called? Why?

Back 35

-Non-Communicating Hydrocephalus
-It prevents the Ventricles from "Communicating" with Subarachnoid space
-results in enlargment of only ventricle where blockage occurs (unless foramina @ 4th ventricle all will be affected)

*cerebral aqueduct is most common site

Front 36

What is Communicating Hydrocephalus? Why is it called Communicating?

Back 36

-movement of CSF into venous system is blocked
-Doesn't affect "Communication" with Subarachnoid Space

*block or lack of arachnoid villi due to meningitis, subarachnoid hemorrhage

Front 37

In _________________ hydrocephalus, ALL parts of the ventricular system are enlarged

Back 37

communicating

Front 38

What is Normal-Pressure Hydrocephalus?

Back 38

ventricles may be initially enlarged and CSF pressure elevated, but the pressure may wax and wane over time and remain at a high normal level.

*may be related to disruption of arachnoid granulations

Front 39

Symptoms of Normal-pressure hydrocephalus

Back 39

include urinary problems (frequency, urgency, or incontinence), impaired gait (ability to step up on a curb, gait apraxia - no weakness, but difficulty) and dementia.

(NPH can mimic Alzheimer’s and Parkinson’s disease.)

Front 40

What is the difference btwn ex Vacua & Hydrocephalus

Back 40

-a result of general atrophy of the brain and relatively larger ventricles because of a loss of white matter (NOT hydrocephalus)
-no increase in ICP
-deficits are related to brain atrophy

Front 41

How do you treat Hydrocephalus?

Back 41

*determine using cautious lumbar puncture
-Shunt away - Often to the Abdomen
-Drain out

Front 42

Compare the Concentration of Plasma and Blood. Na, Cl, Mg, K, Ca, Glucose, and Protein

Back 42

CSF has More Na, Cl, & mg
and Less K, Ca, Glucose, and Protein.

Front 43

What is the foramen of Magendie

Back 43

a midline opening in the delicate caudal roof of the fourth ventricle (inferior medullary velum) connecting it with the cisterna magna.

(allows CSF to leave brain into cranial meninges)

Front 44

Common causes of subarachnoid hemorrhage
What would this lead to?

Back 44

trauma & aneurysm rupture

cisterns would fill w/ blood & outline affected structures

Front 45

where is the choroid plexus found

Back 45

Found in the body, atrium, and inferior horn of the lateral ventricle; the interventricular foramen, the roof of the third ventricle, and caudal roof of the fourth ventricle

Front 46

What is the choroid fissure?

Back 46

groove formed by developing arteries in tela choroidea

Front 47

What is the glomus chorodium?

Back 47

The choroid plexus in the atrium of the lateral ventricle forms a large clump, the glomus choroideum (glomus- L. ball).

*may contain calcifications

Front 48

The villi of the choroid plexus contain choroid epithelial cells with microvili on their luminal surface and _____________________ btwn them

Back 48

tight junctions (zonulae occuludentes)

Front 49

What do these tight junctions create?

Back 49

blood-CSF barrier

*NO BBB in choroid plexus!!!!!!!

Front 50

What provides lymphatic drainage to brain?

Back 50

NOTHING

NO lymphatic drainage

Front 51

T/F
There is a relatively free exchange of fluid btwn brain parenchyma & ventricles

Back 51

TRUE

Front 52

What are tanycytes?

Back 52

specialized ependyma that have basal processes that connect to blood vessels.
Tanycytes have tight junctions between them as opposed to zonula adherens and may transport substances between the blood and ventricles.

Front 53

Name the circumventricular organs

What do they contain?

Back 53

subfornical organ
orgonum vasculosum of the lamina terminalis
subcommissural organ
pineal gland
area postrema of the fourth ventricle

-fenestrated capillaries (no BBB)

Front 54

Conditions/causes for yellow CSF

Back 54

Blood breakdown products
Hyperbilirubinemia

Front 55

Conditions/causes for orange CSF

Back 55

blood breakdown products
high carotenoid ingestion

Front 56

Conditions/causes for pink CSF

Back 56

blood breakdown products

Front 57

Conditions/causes for green CSF

Back 57

hyperbilirubinemia
purulent CSF

Front 58

Conditions/causes for brown CSF

Back 58

meningeal melanomatosis

Front 59

Conditions/causes for cloudy CSF

Back 59

bacterial meningitis
brain abscesses
syphilitic meningitis

(infections)

Front 60

lymphocytes 50 cells/µL with an increase in immunoglobulin G (oligoclonal bands on electrophoresis) produced both by lymphocytes in blood and CSF during an autoimmune reaction attack, would be indicative of what?

Back 60

Multiple Sclerosis

Front 61

How can ventricles be used to assess intracranial masses?

Back 61

-The involvement of the ventricles in this process of tissue displacement offers a good marker for the extent of tissue displacement
-shape of the ventricles and their position relative to other structures

Front 62

what is rhinorrhea?

otorrhea?

Back 62

-fracture of skull that produces a leak of CSF into the nasal cavities
-or external auditory meatus

*primary danger is spread of bacteria into meninges

Front 63

What is a hygroma?

Back 63

lesion that results in disruption of the arachnoid membrane & CSF under a pressure of 100-150 mm of water can dissect a subdural space

Front 64

An expansion of the lateral ventricles without an increase in size of the third or fourth ventricles would indicate a blockage where?

Back 64

at the interventricular foramen (of Monro).

(non-communicating hydrocephalus)

Front 65

What is aqueductal stenosis?

Back 65

noncommunicating/obstructive hydropcephalus at the cerebral aqueduct
(most common site)

Front 66

What is a (+) Queckenstedt's sign?

Back 66

compressing the internal jugular veins should raise CSF pressure by partially blocking return through the arachnoid vili, if pressure does not change, this is a (+) test

Front 67

CSF pathways between ventricles

Back 67

interventricular foramina
cerebral aqueduct

Front 68

ONLY CSF pathways out of ventricles (into subarachnoid space)

Back 68

(via 4th ventricle)
foramen of Magendie
(2) foramina of luschka

Front 69

CSF pathway out of subarachnoid space & into venous circulation

Back 69

arachnoid vili, clustered as granulations, which drain into venous sinuses

Front 70

CSF pressure is pulsatile & corresponds with _________

CSF outflow is dependent on ___________

Back 70

arteriole pulse


venous pressure (when high, prevents CSF outflow)