Alvarez- CSF

Question 1

CSF id formed in the _________ by both ______ and ______

Answer 1

Choroid plexus by both filtration an active transport

Question 2

normal volume of CSF

Answer 2

125-150 mL

Question 3

where is CSF contained?

Answer 3

20% in ventricles and rest in subarachnoid space

Question 4

CSF circulates from the lateral ventricles into the third ventricle then the fourth ventricle via the ________

Answer 4

cerebral aqueduct

Question 5

The CSF if propelled along the _______ by a cranio-caudal pulsate wave induced by flow in cerebral arteries

Answer 5

neuroaxis

Question 6

_________ are cerebral arteries adn the associated EXPANSIONS of the vascular compartment on the cranial vault

Answer 6

wave

Question 7

where is CSF reabsorbed

Answer 7

arachnoid villi

Question 8

what position should patient be to measure the CSF pressure?

Answer 8

flat in the lateral decubitus position

Question 9

normal CSF pressure range

Answer 9

60-250 mm H2O

Question 10

what would cause CSF to look turbid?

Answer 10

min 200 WBC or 400 RBC/microL

Question 11

what would cause CSF to appear bloody?

Answer 11

6000 RBC

Question 12

what happens to RBC (hemoglobin) when enters the CSF? (biproducts)

Answer 12

it is lysed

Hemoglobin –> oxyhemoglobin (pink) –> bilirubin (yellow) –> xanthochromia

Question 13

yellow or pink discoloration of CSF is called?

Answer 13

xanthochromia

Question 14

unexplained xanthochromia can be due to

Answer 14

tramuatic tap

Question 15

normal amount of WBC’s and PMNs in CSF

Answer 15

5 WBC –> normal

>3 PMNs –> abnormal

Question 16

when can CSF cell determination be falsely low?

Answer 16

if measured more than 60 min after LP

Question 17

what is pleocytosis

Answer 17

an elevated CSF WBC concentration

Question 18

patients with meningitis have high ______ in 2/3 of patients

Answer 18

PMNs (then changes to high lymphocytes after 12-24 hrs)

early –> PMNs
Late –> lymphocytes

Question 19

good rule of thumb to calc. WBC count in a traumatic tap

Answer 19

subtract 1 WBC for every 500- 1500 RBCs

Question 20

CSF protein can be elevated by a _______ or _____

Answer 20

subarachnoid hemorrhage or traumatic LP

Question 21

when are immunoglobulins and oligoclonal bands found in CSF

Answer 21

in Multiple sclerosis (also in lyme, autoimmune, brain tumors, lymphoproliferative diseases )

Question 22

what is hypoglycorrhachia

Answer 22

low CSF glucose

Question 23

CSF glucose concentrations less than 18 mg/dL are strongly predictive of

Answer 23

bacterial meningitis

Question 24

normal CSF to glucose ratio

Answer 24

> .6

Question 25

Useful test to differentiate bacterial from viral meningitis

Answer 25

lactate concentration

Question 26

type of meningitis: WBC less than 2000 shows predominance of lymphocytes (in late)

Answer 26

viral

Question 27

type of meningitis: WBC above 1000 with a neutrophilic predominance

Answer 27

Bacterial

Question 28

type of meningitis: CSF protein is less than 150 mg/dL

Answer 28

Viral

Question 29

type of meningitis: CSF protein concentration 250

Answer 29

bacteral

Question 30

type of meningitis: glucose CSF concentration is more than 50 of serum concentration

Answer 30

Viral

Question 31

type of meningitis CSF glucose is below 45 mg/dL

Answer 31

bacterial

Question 32

how do you diagnose a subarachonid hemorrhage

Answer 32

when xanthochromia is detected as soon as 2-3 hours after RBCs have entered subarachnoid space