Cerebrospinal Fluid

General Information

1. The volume (mL) of cerebrospinal Fluid (CSF) in		G7 p.297:80mm
a. a newborn is_____	5
b. an adult is_____	150
2. What is the intracranial:spinal ratio of distribution of CSF in adults?	50:50	G7 p.297:80mm
3. What percentage of CSF is produced in the lateral ventricles?	80%	G7 p.297:80mm
4. The amount of CSF volume produced per day for		G7 p.297:84mm
a. adults is_____	450to750mL/d
b. newborns is_____	25 mL/d
5. What is the rate of CSF formation mL/min in adults?	0.3 to 0.5	G7 p.297:84mm
6. What is the CSF pressure in a patient in lateral decubitus position in the following age groups?		G7 p.297:87mm
a. newborn	9 to 12 cm H2O
d. 1 to 10 years old	< 15
c. young adult	< 18 to 20)
d. adult	< 18 (7 to 15)
7. Where is CSF produced other than in the choroid plexus?		G7 p.297: 95mm
a. i_____ s_____	interstitial space
b. e_____ l_____ of the v_____	ependymal lining of the ventricles
c. d_____ of n_____ r_____ in s_____	dura of nerve root sleeves in spine
8. Complete the following concerning CSF general information:		G7 p.297:115mm
a. What is the rate of CSF production?	0.3to 0.5mL/min
b. That equals how many mL per day?	450 to 750
c. Normal CSF has
i. _____lymphocytes	0 to 5
ii. _____ polymorphonuclear leucocytes (PMN)	0
iii. _____ red blood cells (RBCs)	0
d. White blood cells (WBCs) above _____ is suspicious	5 to 10
e. WBCs above_____ is definitely abnormal.	10 WBCs per cubic mm
f. Subtract_____ WBC for every _____ RBCs.	1; 700
g. Subtract_____ mg protein for every_____ RBCs.	1; 1000	G7 p.298:65mm
9. Does intracranial pressure (ICP) have any effect on CSF formation?	no (The rate of formation is independent of CSF pressure except if the ICP is so high that it causes reduction in cerebral blood flow [CSF].)	G7 p.297:120mm
10. Complete the following concerning CSF general information:		G7 p.297:130mm
a. True or False. CSF absorption is a pressure-dependent phenomenon.	true
b. Where does it take place?
i. a_____v_____	arachnoid villi → dural venons sinuses
ii. c_____ p_____ choroid plexus
iii. l_____	lymphatics

CSF Constituents

11. True or False. The composition of CSF is exactly the same in the ventricles as in the lumbar subarachnoid space.	false (It differs slightly.)	G7 p.297:153mm
12. True or False. The following are normally found in CSF:		G7 p.297:170mm
a. lymphocytes	true
b. mononuclear cells	true
c. polymorphonuclear leucocytes	false
d. RBCs	false
13. True or False. CSF osmolarity and plasma osmolarity are equal, with a ratio 1:1. What is the other constituent that is also equal among the following?		G7 p.298:160m
a. Na	true
b. K+	false
c. Cl^–	false
d. IgG	false
14. True or False. CSF proteins		G7 p.299:110m
a. are equal in adults and children	false (30 in adults and 20 in children)
b. in prematures are ˜ 60mg/dL	false (in prematures 150 mg/dL)
c. in newborn are ˜ 40 mg/dL	false (about 80 in newborn)
d. normally rise ˜ 1 mg/dL/yr of age in adults	true
15. How do you differentiate true leukocytosis from normal white blood cell count included in the traumatic tap?		G7 p.298:30mr
a. ratio of_____ to_____	RBC to WBC
b. normal is_____	700:1
or subtract 1 WBC for every_____ _____	700 RBCs
16. What conditions would affect the WBCRBC ratio of 1:700?		G7 p.. 298:30mm
a. a_____	anemia
b. p_____ l_____	peripheral leukocytosis
17. In case of a traumatic tap, how could you estimate the original count in that CSF in a patient who has anemia or peripheral leukocytosis?	use Fishman’s formula WBC original CSF = WBC CSF – (WBCbld × RBCCSF) RBCbld. Note: WBC and RBC per mm³ in peripheral blood	G7 p.298:30mm
18. How would you estimate the correct protein in the CSF of a traumatic tap?		G7 p.298:65mm
a. Subtract_____ mg of protein	1
b. for every_____ RBCs/mm³.	1000
19. Answer the following about subarachnoid hemorrhage:		G7 p.300:35mm
a. How long does it take for RBC to disappear?	2 weeks
b. How long does it take for xanthochromia to disappear?	many weeks

Artificial CSF

20. True or False. In the use of neuroendoscopy, endogenous CSF and “artificial CSF” should have which of the following characteristics in common?		G7 p.300:84mm
a. physiological temperature	true
b. membrane active ion concentrations	true
c. osmolarity	true
d. pH	true

CSF Fistula

21. The Rosenmüler fossa is located just_____.	inferior to the Cavernous sinus (rosenmüler fossa is located just inferior to the cavernous sinus exposed by drilling the anterior clinoid in a paraclinoid aneurysm. Upper lateral pharyngeal recess. Limited above by the sphenoid and occipital bone. Communicates with the nasal cavities.)	G7 p.301:50mm
22. True or False. The following are characteristics of traumatic CSF fistula:		G7 p.301:77mm
a. They occur in 2 to 3% of all patients with head injury.	true
b. 60% are noted within days of trauma.	true
c. 95% occur within 3 months of trauma.	true
d. < 5% of cases of CSF rhinorrhea stop within 1 week.	false (70% of cases stop within 1 week.)
e. Adult:child ratio is 1:10.	false (adult:child ratio is 10:1)
f. Occurrence is common before age 2 years.	false (occurrence uncommon) prior to 2 years of age)
g. Anosmia is common.	true (78% have anosmia.)
h. Most CSF otorrhea ceases in 5 to 10 days	true
23. Complete the following concerning posttraumatic CSF fistula:		G7 p.301:78mm
a. Rhinorrhea stops within_____ week in_____%	1; 70%
b. Otorrhea stops within_____ days in_____%	5 to 10;80 to 85%	G7 p.301:93mm
24. True or False. Regarding CSF fistulas:		G7 p.301:117mm
a. Anosmia is common in traumatic leaks.	true (78% in traumatic leaks)
b. Anosmia is common in spontaneous leaks.	false (rare in spontaneous leaks. leaks; approximately 5%)
25. The infection rate for		G7 p.301:96mm
a. penetrating injuries and CSF fistulas is _____%.	50%
b. penetrating injuries without fistula is _____%.	4.6%
26. Study Chart.		G7 p.301:110mm
a. Regarding spontaneous CSF fistula: Hint: spontaneous fistula h	sense of smell preserved pneumocephalus is not common otitis media neck stiffness tumor-pituitary-meningioma allergic rhinitis meningitis empty sella syndrome otitis media may result in CSF leak undeveloped floor of anterior fossa sense of smell preserved cribriform plate agenesis sinusitis (paranasal sinusitis) foot plate of stapes is dehiscent—CSF into eustachian tube facial canal fistula into middle ear insidious, ICP is high, intermittent serous effusion transsphenoidal surgery consequence unable to hear due to Mundini dysplasia labyrinthine anomalies adenoma of pituitary hydrocephalus
27. Complete the following concerning meningitis in CSF fistula:		G7 p.302:45mm
a. Posttraumatic CSF leak has an incidence of meningitis of_____%.	5 to 10%
b. Does CSF leakage after surgery have a higher or lower incidence of meningitis?	higher
c. If the leakage site is not identified before surgery failure to close CSF leaks is_____%.	30%(recurrent leak postop)
d. The most common pathogen is_____and its percentage is_____%.	pneumococcus; 83%
28. What are the characteristics of the fluid suggesting the presence of rhinorrhea or otorrhea resulting from a CSF fistula?		G7 p.302:92mm
a. CSF fluid is_____.	as clear as water (unless infected or blood present).
b. True or False. Fluid causes excoriation.	false (Fluid doesn’t cause excoriation of the nose.)
c. Fluid tastes_____.	salty (in rhinorrhea).
d. Glucose is greater than_____mg %.	normal CSF glucose > 30 mg%
e. It contains a special chemical called _____.	B2-transferrin (present in CSF)
f. The special sign when it drops on a sheet is called a_____.	ring sign (An old but unreliable sign. Described as a ring of blood surrounded by a larger concentric ring of clear fluid [suggests the presence of CSF] seen when blood-tinged fluid allowed to drip onto linen [sheet or pillowcase].)
29. Name five characteristics of fluid that suggest the presence of CSF fistula. Hint: bcsfg		G7 p.302:100mm
	B2 transferrin clear salty taste fluid does not excoriate glucose—high > 30 mg % vs. 5 mg % in tears and mucous
30. True or False. The procedure of choice to localize the site of CSF fistula is		G7 p.303:34mm
a. magnetic resonance imaging	false
b. iohexol cisternography	true
c. computed tomography with intravenous contrast	false
d. plain x-ray	false