LABS FOR NEURO DISEASES

Question 1

If the pressure proves to be very high-over____________—one should
obtain the smallest necessary sample of fluid and then,
according to the suspected disease and patient’s condition, administer mannitol or another hyperosmolar agent

Answer 1

400 mm HG

Question 2

Dexamethasone or an equivalent corticosteroid may
generally also be given in an ___________ in order
to produce a sustained reduction in intracranial pressure

Answer 2

initial intravenous dose of

10 mg, followed by doses of 4 to 6 mg every 6 h

Question 3

When in cisternal puncture indicated?

Answer 3

spinal block requiring a sample of

cisternal fluid or for myelography above the lesion.

Question 4

Warming of the analgesic
by rolling the vial between the palms seems to diminish
the _______

Answer 4

burning sensation that accompanies cutaneous

infiltration.

Question 5

The puncture is usually
easiest to perform at the L3-L4 interspace, which corresponds
in many individuals to the________

Answer 5

axial plane of the

iliac crests, or at the interspace above or below

Question 6

______ during the insertion of

the needle indicates that it is placed too far laterally

Answer 6

Sciatic pain

Question 7

L P has few serious complications . The most common
is _______, estimated to occur in one-third of
patients, but in severe form in far fewer.

Answer 7

headache

Question 8

The pain is presumably the result of a _____________ from leakage of fluid at the puncture site and _____________as the patient assumes the erect posture.

Answer 8

reduction of CSF pressure

tugging on cerebral and dural vessels

Question 9

Bleeding into the spinal meningeal or epidural
spaces after lumbar puncture can occur in patients who
are taking anticoagulants (generally with an international
normalized ratio _________, or impaired platelet function (alcoholism,
uremia) .

Answer 9

[INR] > 1 .4), have low platelet counts

<50,000/mm3

Question 10

In the normal adult,

the opening pressure varies from ________

Answer 10

100 to 180 mm Hp, or

8 to 14 mm Hg

Question 11

In an adult, a pressure of
________ indicates intracranial hypotension,
generally caused by leakage of spinal fluid or systemic
dehydration.

Answer 11

50 mm H20 or below

Question 12

The presence of a spinal subarachnoid block was
in the past confirmed by jugular venous compression
_____________

Answer 12

(Queckenstedt test, which tests for a rapid rise in CSF pressure within a few seconds after application of the pressure on the vein).

Question 13

The presence of red blood
cells imparts a hazy or ground-glass appearance; at least
________
must be present to detect this change.

The presence of
______________, depending on the amount of blood;
centrifugation of the fluid or allowing it to stand causes
sedimentation of the RBCs

Answer 13

200 red blood cells (RBCs) per cubic millimeter (mm3)

1,000 to 6,000 RBCs per cubic millimeter imparts a hazy
pink to red color

Question 14

In subarachnoid hemorrhage, the
RBCs begin to hemolyze within a few hours, imparting
a pink-red discoloration _______

Answer 14

(erythrochromia) to the

supernatant fluid;

Question 15

only with large amounts of venous
blood (RBC more than 100,000/mm3) will the supernatant
fluid be faintly xanthochromic due to__________

Answer 15

contamination

with serum bilirubin and lipochromes

Question 16

The pigments that discolor the CSF following subarachnoid

hemorrhage are __________

Answer 16

oxyhemoglobin, bilirubin,

and methemoglobin

Question 17

Oxyhemoglobin
appears within several hours of hemorrhage, becomes
maximal in approximately ________, and diminishes over
a _______

Answer 17

36 h

7- to 9-day period.

Question 18

Bilirubin begins to appear in___________ and increases in amount as the oxyhemoglobin
decreases.

Answer 18

2 to

3 days

Question 19

___________
(through hemoglobin breakdown products, particularly
oxyhemoglobin) also impart a yellow tint to the CSF, as
do blood clots in the subdural or epidural space of the
cranium or spinal column

Answer 19

Hypercarotenemia and hemoglobinemia

Question 20

_________does not enter the
CSF because a low renal threshold for this pigment permits
rapid clearing from the blood

Answer 20

Myoglobin

Question 21

During the first month of life, the CSF may contain a s mall

number of _________

Answer 21

mononuclear cells

Question 22

The protein content of CSF from the basal cisterns is _______and that from the ventricles is ______

Answer 22

10 to 25 mg/ dL

5 to 15 mg/ dL.

Question 23

In children, the protein concentration is somewhat

lower at each level ______

Answer 23

( <20 mg/ dL in the lumbar subarachnoid space).

Question 24

If the serum protein concentrations
are normal, the CSF protein should increase by about __________RBCs provided that the same tube of CSF is
used in determining the cell count and protein content

Answer 24

1mg per 1,000

Question 25

Values in the lumbar CSF of 1,000 mg/ dL or more usually indicate a block to CSF flow; the fluid is then deeply yellow and clots readily because of the presence of fibrinogen; a combination called _______

Answer 25

Froin syndrome

Question 26

The gamma globulin fraction | in CSF is approximately _______ of that in serum.

Answer 26

70 percent

Question 27

There are other notable differences between the protein fractions of CSF and plasma. The CSF always contains a ________ and the plasma does not

Answer 27

prealbumin fraction

Question 28

The concentration of tau protein and in particular the ratio of _________ has found use in the diagnosis of Alzheimer disease

Answer 28

tau to beta-amyloid,

Question 29

The most important is IgG, which may exceed 12 percent of the total CSF protein in diseases such as multiple sclerosis, ________

Answer 29

neurosyphilis, | subacute sclerosing panencephalitis and other chronic viral meningoencephalitides

Question 30

Certain enzymes that originate in the brain, especially the brain-derived fraction of creatine kinase (CK-BB) but also __________ are found in the CSF after stroke, global ischemic hypoxia, or trauma, and have been used as markers of brain damage

Answer 30

enolase and neopterin,

Question 31

Other special markers such as elevation of the 14-3-3 protein, which has some diagnostic significance in __________, B-microglobulin in ______________, __________ in traumatic and other severe brain injuries, and alpha fetoprotein in embryonal tumors of the brain

Answer 31

prion disease meningeal lymphomatosis neuron specific enolase

Question 32

abnormal. After the intravenous injection of glucose, ________ are required to reach equilibrium with the CSF; a similar delay follows the lowering of blood glucose.

Answer 32

2 to 4 h

Question 33

Low values of CSF glucose (hypoglycorrhachia) in the presence of pleocytosis usually indicate _________

Answer 33

bacterial, tuberculous, or fungal | meningitis,

Question 34

As a rule, viral infections of the meninges and brain do not lower the CSF glucose, although low glucose values have been reported in a small number of patients with ___________

Answer 34

mumps meningoencephalitis, and rarely in patients with herpes simplex and zoster infections.

Question 35

false positive for CALAS

Answer 35

false-positive reaction is obtained in the presence of high titers of rheumatoid factor or antitreponemal antibodies,

Question 36

false positive for Venereal Disease Research Laboratories (VORL) slide flocculation test and rapid plasma reagin (RPR) agglutination tes

Answer 36

false-positive reactions may occur with collagen diseases, malaria, and yaws, or with contamination of the CSF by seropositive blood

Question 37

timing of highest sensitivity for PCR tests

Answer 37

These tests are most useful in the first week of infection, when the virus is being reproduced and its genomic material is most

Question 38

Normally, the pH of the CSF is approximately ________somewhat lower than that of arterial blood, which is 7.41 .

Answer 38

7.31

Question 39

The ammonia content of the CSF is __________ that of the arterial blood; it is increased in hepatic encephalopathy, the inherited hyperammonemias, and the Reye syndrome; the concentration corresponds roughly with the severity of the encephalopathy

Answer 39

one-third to onehalf

Question 40

Elevations of _________are found in all of the portosystemic encephalopathies including hepatic coma and the Reye syndrome.

Answer 40

glutamine

Question 41

lactic dehydrogenase, | especially isoenzymes 4 and 5, are elevated in

Answer 41

Bact Men

Question 42

___________ is also elevated in cases of meningeal tumor infiltration, particularly lymphoma,

Answer 42

Lactic dehydrogenase

Question 43

IN CT With contrast, Intravenous contrast in generally withheld if the glomerular filtration rate (GFR) is less than _____

Answer 43

30 mL/ | min/ 1 . 73 m2;

Question 44

MRI also provides images in any plane, but i t has the | great advantage over CT in using _____

Answer 44

nonionizing energy | and providing higher resolution views

Question 45

``` Gradient-echo (GRE), or susceptibility weighted imaging (SWI), is especially sensitive to blood and its breakdown products that appear ________ ```

Answer 45

hypointense

Question 46

Preferential movement of water molecules along a particular direction, for example, parallel to white matter tracts, is referred to as _______

Answer 46

anisotropy

Question 47

Pus-filled abscesses and hypercellular tumors can also show DWI _________, reflecting the limitation of free diffusion of water in these lesions

Answer 47

hyperintensity

Question 48

_______has provided a means of detecting regions of ischemic tissue, and to monitor the elevated blood volume in certain brain tumors

Answer 48

Perfusion imaging

Question 49

____________is a marker of neuronal integrity; and is decreased in both destructive lesions and in circumstances in which there is a reduction in the density of neurons (e.g., edema or glioma that increases the distance between neurons)

Answer 49

N-acetyl aspartate (NAA)

Question 50

_________a marker of membrane turnover, is elevated in some rapidly dividing tumors.

Answer 50

Choline (Cho),

Question 51

________ can be extracted from MRI data and used as a surrogate for local cerebral metabolic activity.

Answer 51

This blood oxygen leveldependent | (BOLD) signal

Question 52

________ a technique which has evolved from PET, uses | isotopes that do not require a cyclotron for their production

Answer 52

Single-photon emission computed tomography | (SPECT),

Question 53

Complication rate from angiography

Answer 53

Overall morbidity from the procedure is approximately 2.5 percent, mainly in the form of worsening of a preexistent vascular lesion or from complications at the site of artery puncture

Question 54

___________can be performed without | contrast, using the "time-of-flight" technique.

Answer 54

MR angiography

Question 55

they allow an accurate localization of the locus of maximal stenosis as reflected by the highest rates of flow and turbulence

Answer 55

carotid duplex

Question 56

The transcranial Doppler uses a_______ signal that is able to pass through the calvarial bone in adults and then receives a frequency-shifted signal from the blood flowing in the lumen of the basal vessels

Answer 56

2-MHz pulsed

Question 57

One of the most remarkable properties of evoked potentials is their resistance to________, and-in comparison with EEG activity-even damage of the cerebral hemispheres.

Answer 57

anesthesia, sedative drugs

Question 58

The interpretation of evoked potentials (visual, auditory, | and somatosensory) is based on the ________

Answer 58

prolongation of the latencies of the waveforms after the stimulus, the interwave latencies, and asymmetries in timing

Question 59

light stimulus | flashing on the retina evokes a discernible waveform in the occipital lobes

Answer 59

occipital driving | response

Question 60

BAEPs are a particularly sensitive means of detecting | lesions of the _______

Answer 60

eighth cranial nerve (vestibular schwannoma and other tumors of the cerebellopontine angle) and of the auditory pathways of the brainstem

Question 61

___________consists of applying 5-per-second painless transcutaneous electrical stimuli to the median, peroneal, or tibial nerves and recording the evoked potentials (for the upper limb) sequentially

Answer 61

SSEP

Question 62

passage points of evoked potentials

Answer 62

Erb point above the clavicle, over the C2 vertebra, and over the opposite parietal cortex, and(for the lower limb) over the lumbar roots of the cauda equina, the nuclei over the cervical spine, and the opposite parietal cortex

Question 63

Delay between the stimulus site and the Erb point or the lumbar spine indicates _________

Answer 63

peripheral nerve disease

Question 64

``` delay from the Erb point (or lumbar spine) to C2 implies an abnormality in the appropriate_________ ```

Answer 64

nerve roots or, more frequently, | in the posterior columns;

Question 65

The normal waveforms are | designated by the symbols _________

Answer 65

P (positive) and N (negative