Disturbances of CSF, Pseudotumor Cerebri and Low-Pressure Syndromes

Question 1

average intracranial volume in an adult

Answer 1

1,700 mL

Question 2

volume of brain

Answer 2

1,200 - 1,400mL

Question 3

volume of CSF

Answer 3

70-160mL mean 104

Question 4

volume of blood

Answer 4

150mL

Question 5

spinal subarachnoid space contains _____ mL of CSF

Answer 5

10-25 mL of CSF

Question 6

absorption of CSF is mainly through

Answer 6

arachnoid villi

Question 7

recumbent, CSF pressure

Answer 7

8mmHg or 110 mm H2O

1mmHg = 13.7 mmH2O

Question 8

As the volume of brain, blood, or CSF continue to
increase, the accommodative mechanisms fail and ICP
rises exponentially, as in an idealized elastance curve. The
normal curve begins its steep ascent at an ICP of approximately _____ mm Hg. After this point, small increments in intracranial volume result in marked elevations in ICP.

Answer 8

25 mmHg

Question 9

As a rule, patients with normal BP retain normal
mental alertness with ICP of ______ mm Hg unless
there is concurrent shift of brain tissue. Stated another
way, coma generally cannot be attributed to elevated ICP
alone.
Only when ICP exceeds _____ mm Hg does cerebral
blood flow diminish to a degree that results in loss of
consciousness

Answer 9

25 to 40 mmHg

40-50mmHg - results in LOC

Question 10

From our own observations, the brain shift and herniation that causes the pupil to dilate on the side of a mass lesion generally occurs at an ICP of _____ mm Hg.

Answer 10

28-34mmHg