CSF DISTURBANCES Flashcards
the 1 ,500-g brain, which has a water content of approximately ___________ percent, weighs only 50 g when suspended in CSF, so the brain virtually floats in its CSF
80
In the adult, the average intracranial volume is 1,700
mL; the volume of the brain is from ___________
CSF volume ranges from _______ (mean: 104 mL),
and that of blood is approximately ________
1 ,200 to 1,400 mL,
70 to 160 mL
150 mL.
the CSF occupies somewhat less than
_______ percent of the intracranial and intraspinal spaces
10
the distance between the caudate
nuclei at the anterior horns gradually widens by approximately
__________, and the width of the third ventricle
increases from _________
1 . 0 to 1 .5 Cm
3 to 6 mm by age 60 years
They established that the average rate
of CSF formation is 21 to 22 mL/h (0.35 mL /min), or
approximately__________ thus the volume of CSF as a
whole is renewed __________
500 mL / d;
4 or 5 times daily.
T OR F
Ionized
compounds, such as hexoses and amino acids, being
relatively insoluble in lipids, enter the CSF slowly unless
facilitated by a membrane transport system.
Ionized
compounds, such as hexoses and amino acids, being
relatively insoluble in lipids, enter the CSF slowly unless
facilitated by a membrane transport system.
What are the components of the BBB
- endothelium of the choroidal and brain capillaries
- plasma membrane and adventitia (Rouget cells) of these vessels
- pericapillary foot processes of astrocytes
________________ help drive the fluid
centrifugally from the ventricular system.
Arterial
pulsations of the choroid plexuses
pacchionian granulations or bodies
microscopic excrescences of arachnoid
membrane that penetrate the dura and protrude into
the superior sagittal sinus and other venous structures
In the recumbent position, ICP and, consequently, CSF
pressure are normally about ___________
(1 mm Hg equals 13.7 mm H20), with an upper limit of
normal that is higher in children than in adults
8 mm Hg or 110 mm H20
T or F
increased venous pressure exerts no
immediate effect on CSF pressure by increasing the volume
of blood in the cerebral veins, venules, and dural
sinuses.
F
The
normal curve begins its steep ascent at an ICP of approximately
__________. After this point, small increments in
intracranial volume result in marked elevations in ICP.
25 mm Hg
The numerical difference between ICP and mean
BP within the cerebral vessels is termed ________
cerebral perfusion
pressure (CPP).
Of the 3 ICP waveforms, which has a clinical significance, , B or C?
A
___________coincide with an increase in intracranial
blood volume, presumably as a result of a temporary
failure of cerebrovascular autoregulation
plateau waves
In a normal adult reclining with the
head and trunk elevated to 45 degrees, the ICP is in the
range of ________
2 to 5 mm Hg
As a rule, patients with normal BP retain normal
mental alertness with ICP of _______ unless
there is concurrent shift of brain tissue
25 to 40 mm Hg
Only when ICP exceeds________ does cerebral
blood flow diminish to a degree that results in loss of
consciousness
40 to 50 mm Hg
the brain shift and herniation that causes
the pupil to dilate on the side of a mass lesion generally
occurs at an ICP of________
28 to 34 mm Hg
Indications for ICP monitoring
with severe traumatic brain injury if they are
over 40 years of age, and have a Glasgow Coma Score
below 9
to ventricular enlargement because of failure of development
of the brain, a state known as ______
colpocephaly
T or F
that the ventricle closest to the obstruction enlarges the
most;
T
The rarely encountered radiologic picture of enlarged
subarachnoid spaces over and between the cerebral hemispheres,
coupled with modest enlargement of the lateral
ventricles has been referred to as _________
external hydrocephalus
The only reported
examples of overproduction of CSF are ___________________, but even in this circumstance, there
is usually an associated ventricular obstruction, either
of the third or fourth ventricle or of one lateral ventricle
papillomas of
the choroid plexus
The cranial
bones fuse by the ______________; for the head to
enlarge, the tension hydrocephalus must develop before
this time
end of the third year
In Dandy Walker, because of bossing of the occiput from
enlargement of the posterior fossa, the head is __________
dolichocephalic
cause the child’s head to move forward and backward
or side-to-side constantly or intermittently at about 2 to
3 Hz.
This is caused by a suprachiasmatic arachnoid cyst or by third ventricular enlargement,
“bobble head” syndrome
Gait associated with NPH pts
Most often, there is
unsteadiness and impairment of balance and shortening
of the step length, with the greatest difficulty being
encountered on stairs and curbs
In NPH, what is this state called: the steps become shorter, with more frequent shuffling and falls; eventually standing and sitting and even turning over in bed become impossible.
“hydrocephalic
astasia-abasia. “
What kind of incontinence among pts with NPH?
the patient is indifferent to his lapses of continence, and
bowel control becomes similarly disordered
“frontal lobe incontinence,”
presumed cause of NPH
aymptomatic fibrosing meningitis
decompensated congenital aqueductal stenosis
