Neuro-Diagnostic Evaluation Flashcards
1
Q
Based on image reconstruction from sets of quantitative x-ray measurements
A
Computed Tomography (CT or CAT scan)
2
Q
contains x-ray source and detectors; tilts from axial to coronal
A
Gantry
3
Q
Highly collimated x-ray beams, which are rotated over many different angles to obtain a ditterential absorption pattern across various rays through a slice of the body
A
Computed Tomography (CT or CAT scan)
4
Q
Differential absorption of x-ray beam by different tissues produce varied levels of density in the image which are measured in
A
Hounsfield units (HU)
5
Q
Hounsfield units
CT Scan
A
Hypodense (black) and Hyperdense (white)
6
Q
CT Scan hypodense tissue
A
Air, fat, water, white matter
7
Q
CT Scan hyperdense tissues
A
Hemorrhage
Calcification
Bone
8
Q
Useful for identifying acute hemorrhage
A
Noncontrast (NCCT)
9
Q
Is NCCT valuable in the assessment of acute neurotrauma
A
No
10
Q
Management of acute stroke - determine cause of S&S, r/o stroke mimics and select patients to be started on RTPA
A
Non contrast computed tomography
11
Q
NCCT & stroke
A
Hyperattenuating vessel filled with acute thrombus (dense MCA sign and dot sign)
• Loss of gray-white matter differentiation
• Loss of insular cortex (insular ribbon sign)
• Decreased density of the basal ganglia
(disappearing basal ganglia sign)
12
Q
Hyperattenuating vessel filled with acute thrombus
A
(dense MCA sign and dot sign)
13
Q
Loss of insular cortex
A
(insular ribbon sign)
14
Q
Decreased density of the basal ganglia
A
Disappearing basal ganglia sign
15
Q
CECT Solution
A
IV lodinated water-soluble contrast
16
Q
• Enhance differences in tissue density, demonstrate vasculature and vascular pathology and detect areas of BBB breakdown (tumors, infections, inflammatory conditions)
• Allergic reaction
• Contrast induced nephropathy
A
Contrast Enhanced Computed Tomography
17
Q
More reliable method for detection of acute brain parenchymal or extra-axial hemorrhage, especially SAH
A
CECT
18
Q
Contraindications for CT Scan
A
Medically and neurologically unstable, uncooperative or claustrophobic
• Patients with pacemakers or metallic implants contraindicated for MRI
19
Q
Indications for Emergency CT
A
• Acute or chronic FND
• Head or facial trauma
• Headache
• Abrupt or worsening
• SAH traumatic vs nontraumatic
• Change in mental status
• New-onset seizure
20
Q
Limitations of CT SCAN
A
• Imaging of posterior fossa - linear artifacts
• lonizing radiation - pregnant
21
Q
CT Scan Advantages
A
• Speed
• Cost
• Availability
22
Q
CTA vs catheter angiography
A
CTA
- More widely available, less specialized skills required, no risk of dissection, stroke or pseudoaneurysm at groin
Limitations
- Time consuming process requiring to edit and generate rendering
23
Q
Allows quantitative measure of CBV, MTT, TTP, CBF
A
CTP
24
Q
Used as a quick screening method in assessment of acute cerebral ischemia and for differentiating between infarct and penumbra
A
CTP
25
Infarct CTP
Prolonged MTT
Dec CBV
Dec CBF
26
Ischemic penumbra
* salvagable
Prolonged MTT &TTP w/ N/ inc CBV an dec CBF
(Compensatory vasodilation)
27
Repeating scan during a bolus of IV contrast produces dynamic set of images that are real time 4D images of blood flow through the intracranial vessels
CTA
28
CTA + combined with functional images of the brain parenchymal blood flow
CTP
29
Origin of MRI Signal
hydrogen nuclei that consist of a single proton that is constantly spinning
30
Ability to distinguish different soft tissues and identify pathologic abnormalities
Significantly higher contrast between different tissues compared to CT or
UTZ
Magnetic Resonance Imaging (MRI)
31
Most precise and sensitive imaging for detecting CNS tissue pathology
Magnetic Resonance Imaging (MRI)
32
MRI Limitations
Cost
• Lengthy
• Distortion of images by artifacts
• Claustrophobia and level of cooperation of patient
• Implanted devices ie pacemakers, infusion pumps, cochlear implants, aneurysm clips
• Machines ie ventilator
• ? Pregnant - development of cataracts of fetuses of animals
33
MRI Safety concerns
• Powerful magnetic field = tissue heating effects, movement of object within
• Gadolinium chelates - contrast agent; deposition in tissues, resulting fibrosis in patients with renal dysfunction has been reported (NEPHROGENIC SYSTEMIC FIBROSIS)
34
contrast agent; deposition in tissues, resulting fibrosis in patients with renal dysfunction has been reported (NEPHROGENIC SYSTEMIC FIBROSIS)
Gadolinium chelates
35
MRI Basic Sequence
T1-weighted
• T2-weighted
• Fluid attenuated inversion
recovery T2-weighted (T2 FLAIR)
• Diffusion-weighted (DWI)
• Susceptibility-weighted
• Post-contrast enhanced images
36
MRI Terms
• Hypointense - dark
• Hyperintense - bright
• Isointense
37
Display brain and spinal cord anatomy
• Evaluate subacute hemorrhage, lipids, paramagnetic metals or proteinaceous composition of lesions (short T1
relaxation time = Bright)
T1W
38
T1W Appearance
Dark Csf
Gray M = Dark
White M = Bright
39
Baseline for comparison to CE images
T1W
40
Display brain and spinal cord pathology as evidenced by increased tissue water content
T2W
41
Emphasize long T2 relaxation times=
Bright
42
short T2 relaxation time =
Dark
43
T2W Appearance
White matter - dark
Gray matter - bright
CSF - bright
44
Used to eliminate signal from CSF
T2 FLAIR
45
Highlighting subtle brain pathology; specifically useful for white matter diseases and lesions that are near CSF compartments
Multiple sclerosis & supratentorial lesions
T2 FLAIR
46
Demonstrates nonenhancing tumor components as well as associated mass effect and edema
T2 FLAIR
47
T2 FLAIR Appearance
CSF is dark - suppress CSF or "free water" not contained within tissue
48
periventricular white matter lesions, radially oriented to the bodies of the lateral ventricles
Multiple sclerosis
49
periventricular, deep and subcortical/juxtacortical white matter and corpus callosum
Supratentorial Lesion
50
Used to eliminate signal from fat
• Short tau inversion recovery (STIR)
51
Useful in diagnosing fat containing lesions like lipoma and dermoid cyst
• Short tau inversion recovery (STIR)
52
they also employ an inversion pulse; however, they are
timed not to suppress CSF
signal but rather to increase the conspicuity of lesions and suppress signal from fat,
T2W
53
Detection of early ischemic brain injury
Diffusion Weighted Imaging (DWI)
54
measures extent to which the diffusivity of water is restricted from free diffusion, presumably due to structural barriers such as cell membranes or association of water with larger molecules that have lower diffusion coefficients
Apparent Diffusion Coefficient (ADC)
55
• MRI can help with identifying chronicity of infarct
Diffusion Weighted Imaging (DWI)
56
True restricted diffusion =
bright DWI; dark on ADC
57
- failure of Na-K ATPase pump leading to intracellular swelling and reduced intercellular space thus limiting the free movement of water =
hyperintense on DWI
58
GRE
Sensitivity to small amounts of blood and blood breakdown products =
Hypointense
59
GRE
Characterize tissue components such as
calcification or iron content
60
Used for remote hemorrhage
Gradient Recalled Echo
(GRE)
61
• Signifies breakdown of blood brain barrier (BBB)
• Characterize lesions from brain tumors, metastases to infectious and inflammatory
• Gadolinium Contrast Enhancement
62
• Gadolinium Contrast Enhancement
Contraindications
• Severe allergy
• Renal failure;
63
Time of flight technique
• Signal is related to flow phenomenon
• Noninvasive
• No contrast
Magnetic Resonance Angiography
64
MRA Application
Stenosis
• Thrombosis
• Dissections
• Aneurysms
65
CE MRA
• CE - evaluation following intervention for aneurysm, cerebrovascular malformations (AVM)
• CE MRA - evaluate neck vasculature
66
Evaluate for patency of dural venous sinuses in venous sinus stenosis or thrombosis
Magnetic Resonance Venography
67
Use of magnetic resonance for localization of cerebral activation
Functional MRI
68
• Used to obtain functional information by visualizing cortical activity
Functional MRI
69
• Detects subtle changes in blood flow/blood oxygenation in response to stimuli or actions
Functional MRI
70
Clinical application of functional MRI
• Cortical mapping of known cognitive and motor functional units
• Presurgical and pretherapeutic planning
71
MRI technique that measures water molecule diffusion and its direction
Diffusion Tensor Imaging
72
Diffusion Tensor Imaging aka
Diffusion tractography
73
map of neural connections
Human connectome
74
Deduce axonal fiber orientation and create 3D color coded maps of white matter tracts
Diffusion Tensor Imaging
75
L to R
Red
76
A to P
Green
77
S to I
Blue
78
Diffusion Tensor Imaging clinical application
Asses the integrity of white matter tracts
• Presurgical and pretherapeutic planning
79
Used as a problem solving technique in attempt to differentiate lesions
MR Spectroscopy (MRS)
80
Relative amplitude of resonance peaks reflects the relative concentrations of metabolites
MR Spectroscopy (MRS)
81
Tumor recurrence vs radiation necrosis
Tumor recurrence
(higher choline to creatine ratio)
82
signify normal neuronal tissue / neuronal integrity
• Decreased in destructive lesions and if there is a decrease in density of neurons
N-acetylaspartate (NAA)
83
signify energy stores
Creatine
84
signify components of the cell membrane and myelin / membrane turnover
• Increased in rapidly dividing tumors
Choline
85
signify anaerobic metabolism
Lactate
86
marker of astrocytes/astrogliosis seen in
MS
Inositol/myoinositol
87
Quantifying blood flow through biologic tissues
Cerebral blood volume, cerebral blood flow and mean transit time
MR Perfusion Imaging
88
MR Perfusion Imaging Clinical Application
• Cerebrovascular disease - stroke or vasospasm - MTT measures perfusion delay and are sensitive indicators of small reductions of cerebral perfusion
• Brain tumors and metastases - histologic tumor grade and can help characterize response to treatment of tumor
89
PET meaning
Positron Emission Tomography
90
SPECT meaning
Single -Photon Emission
Computed Tomography (SPECT)
91
Molecular imaging used to better understand the biochemical processes that underlie disease
PET and SPECT
92
A radioactive compound, in trace amounts, with a pharmacokinetic behavior that targets a molecular pathway related to the pathology of a certain disease is administered to the patient = radioligand
PET and SPECT
93
A radioactive compound, in trace amounts, with a pharmacokinetic behavior that targets a molecular pathway related to the pathology of a certain disease is administered to the patient =
Radioligand
94
• Real-time, noninvasive, comprehensive and affordable
• Repeatable, portable
• Harmless
Neurovascular Ultrasound
95
Neurovascular Ultrasound
Types
Extracranial ultrasound
Transcranial ultrasound
96
Example of extracranial ultrasound
(duplex ultrasound or color doppler)
97
Transcranial ultrasound examples
(transcranial doppler)
98
Screening extracranial carotid and vertebral arteries for atherosclerosis
Extracranial Ultrasound
99
Real-time imaging of anatomy, physiology (hemodynamics) and pathophysiology of extracranial circulation
Extracranial ultrasound
100
Carotid imaging for detection of carotid stenosis, assessment after carotid surgery or stenting
Extracranial Ultrasound
101
Carotid plaque size, morphology and carotid intima-media thickness
increased risk of stroke
Plaque surface irregularity
102
increased risk of stroke or MI
Echoluscent carotid plaque (soft)
103
lower risk but may be a marker of presence of active plaque in other vascular beds
Echodense carotid plaque (calcified)
104
Indications for Extracranial Ultrasound Examination (Carotid Artery Ultrasound)
• Evaluation of Cerebral ischemia, stroke or TIA
• Evaluation of patient with cervical bruit
• Evaluation of pulsatile mass in the neck
• Evaluation of blunt neck trauma
• Preoperative evaluation of patients undergoing major cardiovascular or other major surgical procedures
• Drop attacks or syncope (?VB insufficiency or bilateral carotid artery disease)
• Vasculitis of extracranial arteries
• Follow up
• Evaluation of postop carotid endarterectomy or carotid stenting
• Evaluation of suspected carotid or VA dissection
105
Noninvasive ultrasound technology that monitors blood flow velocity and blood flow direction in large intracranial arteries
Intracranial Ultrasound (Transcranial Doppler or TCD)
106
Clinical application of Intracranial ultrasound
• Stenosis or occlusion of a major intracranial artery in COW or VB system and monitoring of thrombolytic activity in acute stroke
• Vasospasm in SAH - increased blood flow velocity
• Brain death
107
Limitations of Intracranial ultrasound
• Operator dependent
• 10-15% rate of inability to perform TCD due to inadequate windows
• Limited to large cerebral arteries
108
Ultrasound in babies
Transducer placed over
open fontanelles or thin calvarium
109
Indications for ultrasound for babies
Intracerebral and subdural hemorrhages, mass lesions, congenital defects
110
INR Meaning
Interventional Neuroradiology
111
ESNR Meaning
Endovascular Surgical
Neuroradiology
112
• Invasive, diagnostic and therapeutic interventions
Interventional Neuroradiology
(INR) or Endovascular Surgical
Neuroradiology (ESNR)
113
High resolution images of extracranial and intracranial vasculature
Cerebral Angiography
114
Accessing the femoral nerve and threading a catheter into the precerebral vessels
Cerebral Angiography
115
Gold standard for viewing cerebral blood vessels
Cerebral Angiography
116
soft tissue is eliminated from image leaving only the contrast enhanced vasculature (DSA)
Digital subtraction process
117
Cerebral Angiography
Visualization of cerebral and SC vessels to a resolution of- lumen diameter
‹1mm
118
Advantages of Cerebral Angiography
Improved temporal resolution
• Functions as both diagnostic and therapeutic
119
Indications for cerebral angiography
Occluded or stenotic vessels
• Stroke - endovascular recanalization and reperfusion - IA thrombolysis, thrombectomy
• Carotid artery stenosis
• Arterial dissections
• Aneurysms
• AVMs and other vascular malformations
• Vasculitic narrowing ("beading")
• Dural venous sinus thrombosis
120
Possible complication for cerebral angiography
Artery puncture
• Dislodged plaque - cerebral or systemic ischemic lesions
• Dissection
• Thrombus formation over catheter tip
• Vasospasm
• Disruption of BBB
121
• Measure spontaneous electrical activity generated by neural structures
• Functional assessment of CNS
• Waveforms
Electroencephalography (EEG)
Evoked Potentials (EP)
122
Reflects electrical currents flowing in the extracellular spaces of the brain and are summated effects of innumerable excitatory and inhibitory potentials of the cortical neurons
Electroencephalography (EEG)
123
Electroencephalography
Cortical neurons are highly influenced and synchronized by
Thalamus and higher brainstem reticular formation
124
Eeg
Each channel represents the difference in electrical potential between the electrodes
Positive (downward) and negative (upward)
strokes
125
Varies with state of arousal and age
• Wakefulness - alpha rhythm
Electroencephalography (EEG)
126
EEG Activation procedures
• Hyperventilation
• Flashes of light (photic stimulation)
• Drowsy states
127
EEG
Clinical Applications
Epilepsy - epileptiform discharges (spikes, polyspikes, sharp waves, spike and slow waves); localization and type of discharge helps identify a specific syndrome
• Focal brain lesion or dysfunction
• Diffuse brain dysfunction or injury - toxic, metabolic, diffuse hypoxic-ischemic and other global injuries to the brain result in generalized nonspecific EEG changes
• Intraoperative neuromonitoring
128
epileptiform discharges (spikes, polyspikes, sharp waves, spike and slow waves); localization and type of discharge helps identify a specific syndrome
Epilepsy
129
toxic, metabolic, diffuse hypoxic-ischemic and other global injuries to the brain result in generalized nonspecific EEG changes
Diffuse brain dysfunction or injury
130
Potentials generated by the nervous system in response to stimuli
Evoked potentials
131
• Composed of a stereotyped sequence of waveforms that are labelled by their polarity (positive or negative) and their peak latency from the time of stimulation
Evoked Potentials
132
• Dysfunction of sensory or motor pathways due to disease or injury leads to increased waveform latency
Evoked Potentials
133
• Complete interruption of conduction or destruction of the neural generators results in the absence of wave forms
Evoked Potentials
134
Type of evoked Potentials
Somatosensory
Visual
Motor
Brainstem Auditory
135
Elicited by light electrical stimulation of peripheral nerves and reflect sequential activation of structures along sensory pathway (DCML)
Somatosensory Evoked Potentials (SSEP)
136
Reveal dysfunction in the sensory pathway that is not clinically apparent
• Capacity to localize a lesion
Somatosensory Evoked Potentials (SSEP)
137
Obtained by stimulation with an alternating checkerboard pattern of black and white squares (changes color at regular frequency)
Visual Evoked Potentials (VEPs)
138
Visual Evoked Potentials (VEPs)
Produces an occipital positive response with mean latency of
100 ms
139
• Conduction delay
• Used in patients with acute optic neuritis, demyelinating diseases (ie acute disseminated encephalomyelitis, NMO), ischemic optic neuropathy, compression of optic nerve, retinal diseases
Visual Evoked Potentials (VEPs)
140
Auditory stimulus (clicks) delivered to one ear, recorded through scalp electrodes and superimposed on each other
Brainstem Auditory Evoked Potentials (BAER)
141
Brainstem Auditory Evoked Potentials (BAER)
Consists of
7 waveforms
• I - peripheral portion of auditory nerves
• Ill - superior olivary complex
• V - inferior colliculus
142
• Sensitive to lesions affecting the CN VIII and auditory pathways in the brainstem
• Can be used to assess infants and young children who cannot cooperate with audiometry
Brainstem Auditory Evoked Potentials (BAER)
143
Tests integrity of motor pathways
Motor Evoked Potentials
144
Motor Evoked Potentials
Elicited by
transcranial magnetic stimulation of primary motor cortex
145
Transcutaneous stimulation of motor or sensory nerves and recording of an elicited response in terms of CMAP or
SNAP
• SNAP and CMAP distal/onset latencies, amplitudes, conduction velocities
Nerve Conduction Studies (NCS)
146
• Measure speed and strength of an electrical impulse conducted along a peripheral nerve
Nerve Conduction Studies (NCS)
147
Nerve Conduction Studies (NCS)
SNAP waveform produced by
large la axons
148
recording electrodes over motor endplate region of an innervated muscle
Motor nerves
149
capture the electrical potential generated by
depolarization of the muscle = CMAP
Recording electrodes
150
summated number of responsive axons
Amplitude
151
time difference between the stimulus and the waveform onset; measure of nerve speed
Distal/onset latency
152
- latency and distance between stimulus and recording electrode; maximal velocity propagation of action potentials in largest and fastest conducting fibers
Conduction velocity
153
depends on intact myelinated nerve = rapid action potential propagation
• Latency and conduction velocity
154
depends on the number of functioning axons within the nerve
Amplitude
155
Slowing of CV and prolonged latency =
demyelination
156
• Decreased SNAP/CMAP amplitude =
axonal loss
157
Information about the proximal segments of a nerve, including the spinal roots
Late responses
158
submaximal stimulation of mixed nerves induces a muscle contraction after a latency longer than the direct motor response
H Reflex
159
Describe H Reflex
• Electrical representation of ankle jerk
Cumulative time for impulses to reach SC via sensory fibers, synapse with anterior horn cells and transmitted through motor fibers to muscle
• Useful in S1 radiculopathy and polyradiculopathies
160
supramaximal stimulus of a mixed nerve or pure motor nerve
F response
161
F Response description
Result of impulses that travel antidromically in the motor nerves to the AHC which are activated and produce an orthodromic response recorded at the distal muscle
* • Representative of proximal motor nerve and root conduction
162
Needle electrode is inserted into muscle which is activated by voluntary contraction at different levels of effort
Needle Electromyography
163
Every muscle fiber fires following a nerve action potential from motor neuron
• A single motor axon with all of its branches and innervated muscle fibers is known as a motor unit
Needle Electromyography
164
primarily determined by number of activated MUPs and their firing rates
Strength
165
Insertional and spontaneous activity, MUP Configuration, recruitment
Assess
166
Needle EMG
Insertional activity
brief burst of electrical activity provoked by EMG
needle as it moves through the muscle
167
Normal resting muscle is
Electrically silent
168
Needle EMG
spontaneous activity
fibrillations, sharp waves - hallmark of denervation (10-14 days after); may also be seen in myopathies
• Fibrillation
• Fasciculations
• Complex repetitive discharges (CRDs)
• Myotonic discharges
• Myokymic discharges
• Neuromyotonia
169
destruction of muscle fiber; reduced number of MUPs, short duration, low amplitude and polyphasic; high pitched cracking sound like rain fall on tin roof
Myopathies
170
high amplitude, long duration, polyphasic MUPs (chronic neurogenic injury)
Reinnervation
171
reduced number but normal MUPs
Denervation
172
Abnormal EMG
Increased or decreased insertional activity
• Abnormal spontaneous activity during relaxed state
• Fibrillations, positive sharp waves, fasciculations, cramp potentials, myotonia, myokemia
• Abnormal amplitude, duration and shape of a single MUPs
• Decrease in number and changes in firing pattern such as recruitment
• Variation in amplitude and number of phases of MUPs
173
Assess neuromuscular transmission using a standard motor nerve conduction setup to deliver a series of supramaximal stimulations to a motor nerve at a specific frequency while recording each
СМАР
• Repetitive Nerve Stimulation (RNS)
174
• Repetitive Nerve Stimulation (RNS)
Trains of — waveforms are evaluated for decrease in area and amplitude
4-10
175
• postsynaptic NMJ dysfunction
• decremental responses
Myasthenia gravis
176
• A single muscle fiber action potential is measured
Single Fiber EMG (SFEMG)
177
interval between stimulus and response varies with each stimulus
Jitter
178
In NMJ dysfunction
Jitter inc
179
Uses light scattering to produce cross sectional images of the retina allowing evaluation of the different layers
Optical Coherence Tomography (OCT)
180
lights of varying intensities and sizes appearing in different areas of the visual field while patient fixates on a spot
Perimeter
181
Visual fields
Perimetry
182
Color vision
Ishihara plate
183
Visual Acuity
Sneklen Chart, E Chart
184
plots the threshold of hearing in decibels with frequencies 8-
125dB
• N = better than 15 dB
Audiogram
185
BAER Meaning
Brainstem auditory evoked respons
186
uses electrodes to record eye movements, supplemented by VNG where goggles with infrared cameras track eye movement
Electronystagmography/Videonystagmo graphy
187
saccade velocity and accuracy and latency along with smooth pursuit and optokinetic nystagmus
• Evaluation for spontaneous nystagmus
Ocular motor testing
188
Evaluation for spontaneous nystagmus
• Positional testing with Dix Hallpike
• Caloric testing
Electronystagmography/Videonystagmo graphy
189
Neuropsychological Evaluation
Intellectual ability - WAIS IV questionnaire; has subtests that assess specific areas of cognition
• Memory
• Processing speed
• Perceptual
• Visual Perception and Construction
• Language
• Executive function - ability to plan, sequence and monitor behavior
• Motor and praxis
• Attention
• Concept formation and reasoning
• Personality and emotional status
190
Tool for evaluating or quantifying the effects of disease on cognition and behavior
• Serial evaluations may show change with time
• Assess area of competence
Neuropsychological Evaluation
191
Neuropsychological Evaluation used in
Used in:
• Dementia
• Epilepsy
• Psychiatric conditions
• Learning disability
192
Indications of lumbar puncture
• Performed to obtain pressure measurements and procure CSF
sample
• Instillation of anesthetics, antibiotics, antitumor agents
• Drainage to reduce CSF pressure
• Injection of radioopaque substances in myelography
193
Lumbar Puncture safety concern
• Possibility of cerebellar or transtentorial herniation in patients with very high CSF pressure esp if from intracranial mass lesion
194
Lumbar puncture steps
• Lateral decubitus position "fetal position"
• Sit upright with neck and back flexed forward
• Opening pressure measured in lateral recumbent position
• L3-14, L4-L5 or L5-S1 interspace
• Line joining superior aspect of the iliac crest (intercristal line)
identifies the L4 spinous process or L3-L4 interspace
• Sterilize and anesthesize
• Spinal needle
• Insert and advanced slowly at angle directed towards the umbilicus
• Remove stylet and measure OP and collect
195
Lumbar puncture most common cmplication
Headache - upright position due to reduction of CSF pressure from leakage of fluid at the puncture site and tugging on cerebral and dural vessels
196
Position & tool for CSF Analysis
Patient in lateral decubitus position
• Manometer
197
CSF pressure adult
100-180mmH20;
198
CSF Pressure children
30 - 60mmH20
199
Inc ICP
• > 200mmH20
200
Intracranial Hypotension
• < 50mmH20
201
(Froin syndrome) - high CSF protein due to block in CSF flow
Yellow and clots readily due to fibrinogen
202
Opaque haziness
pleocytosis (increased WBC)
203
Hazy pink - red - blood
(bloody tap vs SAH)
204
Acellular
(0-5 lymphocytes per cubic mm)
205
Proteins
15-45 mg/dL
• Amount of CSF protein is proportional to the length of time it is in contact with the blood-CSF barrier
• Spillage of blood including serum proteins
• Opening of blood-CSF barrier in brain tumors
206
CSFelectrophoresis
• Albumin, pre-albumin, globulin fractions, immunoglobulin (IgG major Ig in CSF)
207
Glucose
2/3 of that in the blood (0.6-0.7 of serum concentrations)
• Hypoglycorrhachia with pleocytosis - bacterial, tuberculous, fungal meningitis (active metabolism)
• As a rule, viral infections of the meninges and brain do NOT lower CS glucose
208
bacterial, tuberculous, fungal meningitis (active metabolism)
• Hypoglycorrhachia with pleocytosis
209
Serologic and Virologic Tests
VDRL, RPR - neurosyphilis
• PCR for herpes virus, CMV, TB
• 14-3-3 - CJD
210
Brain Biopsy
Mass lesions
• Stereotactic guided biopsy
• Frozen sections
211
Muscle Biopsy
Neurogenic vs myogenic disorders
• Moderately affected muscles
212
Nerve biopay
Mostly used: sural nerve
• Clinical Applications:
• Vasculitis
• Sarcoid neuropathy
• Amyloidosis
• Leprous neuropathy
• Other peripheral neuropathies
