Meninges & CSF Flashcards Preview

Term IV: Neuro > Meninges & CSF > Flashcards

Flashcards in Meninges & CSF Deck (28):
1

Two layers of dura mater

Meningeal and periosteal

2

Where does periosteal layer end?

Foramen magnum

3

Where in the brain is CSF?

subarachnoid space

4

Through what structures does CSF enter venous sinuses?

Arachnoid villi/granulations

5

What veins cross arachnoid, subdural, and meningeal dura to empty into sinuses?

Subdural bridging veins

6

Where should you perform a lumbar puncture for adults and children?

Under L3 - adults
Under L4 - children

7

What is the epidural space used for? What structure do you cross?

Epidural block - anesthesia

Ligamentum flavum

8

4 functions of CSF

1. Buoyancy to brain
2. Dampens effects of trauma
3. Stable ionic env
4. Removes metabolites from brain ECF

9

What color is normal CSF? Glucose level? Protein level? Cells?

Clear - low protein and glucose, acellular

10

What structure makes CSF? What type of endothelium does it have?

Choroid plexus - fenestrated, leaky capillary endothelium

11

What enzyme is needed for CSF production?

Carbonic anhydrase

12

What cells have cilia to move CSF along?

Ependymal cells

13

Trace flow of CSF starting from choroid plexus.

Choroid plexus --> lateral ventricles --> foramina of Monro --> third ventricle --> cerebral aqueduct of Sylvisu --> fourth ventricle --> foramina of Luschkas and Magendie --> cisterna magna --> spinal cord and brain --> arachnoid villi --> venous system

14

Inflammation or infection of meninges

Symptoms?

Meningitis

Headache, fever, neck stiffness, photophobia, encephalopathy

15

Benign, slow growing, asymptomatic tumor of meninges

Meningioma

16

Lens-shaped bleed often caused by damage to MMA due to trauma

Crosses cranial sutures?

Epidural bleed

Can't cross

17

Crescent-shaped bleed often caused by trauma to bridging veins

Crosses cranial sutures?

Subdural bleed

Can cross sutures, but not midline

18

Diffuse bleed commonly caused by trauma or aneurysmal rupture

Subarachnoid bleed

19

Blocked CSF flow

What are the two types?

Hydrocephalus

Non-communicating (obstructive)

Communicating (impaired absorption)

20

What are symptoms of increased intracranial pressure (ICP)?

Headache, vomiting, Cushing's reflex, bradycardia, HTN, papilledema

21

What can cause ICP (increased intracranial pressure)?

Diffuse or focal edema in brain, hydrocephalus, meningitis, bleeds, tumors, abscesses

22

What does increased protein levels in CSF indicate?

Infection or inflammation (Abs from GBS or MS for example)

23

What does increased white cells and decreased glucose in CSF indicate?

Infection or inflammation

Neutrophils - bac. meningitis
Lymphocytes - aseptic process

24

What does increased red cells in CSF indicate?

Subarachnoid hemorrhage, hemorrhagic meningitis (HSV)

25

Functions of blood-brain barrier?

Keep plasma, toxins, proteins, growth factors, NT's in and out

Keep stable ionic environment

26

What three layers form the blood-brain barrier?

Tight junctions in endothelial cells, foot processes of astrocytes, capillary basement membrane

27

Name two areas of the brain that do NOT have a BBB and their function:

1. Area postrema (senses toxins, causes vomiting)
2. OVLT (organum vasculosum of lamina terminalis) - senses osmolar changes, makes ADH decisions

28

What property determines if something can cross BBB?

What must be used if transport is too fast? If too slow?

Lipid solubility/hydrophobicity

Too fast: Carrier-mediated transport

Too slow: Albumin-bound