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Neuro-Diagnostic Evaluation Flashcards

1
Q

Based on image reconstruction from sets of quantitative x-ray measurements

A

Computed Tomography (CT or CAT scan)

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2
Q

contains x-ray source and detectors; tilts from axial to coronal

A

Gantry

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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)

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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)

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5
Q

Hounsfield units

CT Scan

A

Hypodense (black) and Hyperdense (white)

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6
Q

CT Scan hypodense tissue

A

Air, fat, water, white matter

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7
Q

CT Scan hyperdense tissues

A

Hemorrhage
Calcification
Bone

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8
Q

Useful for identifying acute hemorrhage

A

Noncontrast (NCCT)

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9
Q

Is NCCT valuable in the assessment of acute neurotrauma

A

No

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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

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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)

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12
Q

Hyperattenuating vessel filled with acute thrombus

A

(dense MCA sign and dot sign)

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13
Q

Loss of insular cortex

A

(insular ribbon sign)

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14
Q

Decreased density of the basal ganglia

A

Disappearing basal ganglia sign

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15
Q

CECT Solution

A

IV lodinated water-soluble contrast

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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

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17
Q

More reliable method for detection of acute brain parenchymal or extra-axial hemorrhage, especially SAH

A

CECT

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18
Q

Contraindications for CT Scan

A

Medically and neurologically unstable, uncooperative or claustrophobic

• Patients with pacemakers or metallic implants contraindicated for MRI

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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

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20
Q

Limitations of CT SCAN

A

• Imaging of posterior fossa - linear artifacts
• lonizing radiation - pregnant

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21
Q

CT Scan Advantages

A

• Speed
• Cost
• Availability

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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

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23
Q

Allows quantitative measure of CBV, MTT, TTP, CBF

A

CTP

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24
Q

Used as a quick screening method in assessment of acute cerebral ischemia and for differentiating between infarct and penumbra

A

CTP

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25
Q

Infarct CTP

A

Prolonged MTT
Dec CBV
Dec CBF

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26
Q

Ischemic penumbra

A
  • salvagable

Prolonged MTT &TTP w/ N/ inc CBV an dec CBF
(Compensatory vasodilation)

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27
Q

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

A

CTA

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28
Q

CTA + combined with functional images of the brain parenchymal blood flow

A

CTP

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29
Q

Origin of MRI Signal

A

hydrogen nuclei that consist of a single proton that is constantly spinning

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30
Q

Ability to distinguish different soft tissues and identify pathologic abnormalities

Significantly higher contrast between different tissues compared to CT or
UTZ

A

Magnetic Resonance Imaging (MRI)

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31
Q

Most precise and sensitive imaging for detecting CNS tissue pathology

A

Magnetic Resonance Imaging (MRI)

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32
Q

MRI Limitations

A

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

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33
Q

MRI Safety concerns

A

• 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)

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34
Q

contrast agent; deposition in tissues, resulting fibrosis in patients with renal dysfunction has been reported (NEPHROGENIC SYSTEMIC FIBROSIS)

A

Gadolinium chelates

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35
Q

MRI Basic Sequence

A

T1-weighted
• T2-weighted
• Fluid attenuated inversion
recovery T2-weighted (T2 FLAIR)
• Diffusion-weighted (DWI)
• Susceptibility-weighted
• Post-contrast enhanced images

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36
Q

MRI Terms

A

• Hypointense - dark
• Hyperintense - bright
• Isointense

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37
Q

Display brain and spinal cord anatomy
• Evaluate subacute hemorrhage, lipids, paramagnetic metals or proteinaceous composition of lesions (short T1
relaxation time = Bright)

A

T1W

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38
Q

T1W Appearance

A

Dark Csf
Gray M = Dark
White M = Bright

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39
Q

Baseline for comparison to CE images

A

T1W

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40
Q

Display brain and spinal cord pathology as evidenced by increased tissue water content

A

T2W

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41
Q

Emphasize long T2 relaxation times=

A

Bright

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42
Q

short T2 relaxation time =

A

Dark

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43
Q

T2W Appearance

A

White matter - dark
Gray matter - bright
CSF - bright

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44
Q

Used to eliminate signal from CSF

A

T2 FLAIR

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45
Q

Highlighting subtle brain pathology; specifically useful for white matter diseases and lesions that are near CSF compartments

Multiple sclerosis & supratentorial lesions

A

T2 FLAIR

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46
Q

Demonstrates nonenhancing tumor components as well as associated mass effect and edema

A

T2 FLAIR

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47
Q

T2 FLAIR Appearance

A

CSF is dark - suppress CSF or “free water” not contained within tissue

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48
Q

periventricular white matter lesions, radially oriented to the bodies of the lateral ventricles

A

Multiple sclerosis

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49
Q

periventricular, deep and subcortical/juxtacortical white matter and corpus callosum

A

Supratentorial Lesion

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50
Q

Used to eliminate signal from fat

A

• Short tau inversion recovery (STIR)

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51
Q

Useful in diagnosing fat containing lesions like lipoma and dermoid cyst

A

• Short tau inversion recovery (STIR)

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52
Q

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,

A

T2W

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53
Q

Detection of early ischemic brain injury

A

Diffusion Weighted Imaging (DWI)

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54
Q

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

A

Apparent Diffusion Coefficient (ADC)

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55
Q

• MRI can help with identifying chronicity of infarct

A

Diffusion Weighted Imaging (DWI)

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56
Q

True restricted diffusion =

A

bright DWI; dark on ADC

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57
Q
  • failure of Na-K ATPase pump leading to intracellular swelling and reduced intercellular space thus limiting the free movement of water =
A

hyperintense on DWI

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58
Q

GRE

Sensitivity to small amounts of blood and blood breakdown products =

A

Hypointense

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59
Q

GRE

Characterize tissue components such as

A

calcification or iron content

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60
Q

Used for remote hemorrhage

A

Gradient Recalled Echo
(GRE)

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61
Q

• Signifies breakdown of blood brain barrier (BBB)
• Characterize lesions from brain tumors, metastases to infectious and inflammatory

A

• Gadolinium Contrast Enhancement

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62
Q

• Gadolinium Contrast Enhancement

Contraindications

A

• Severe allergy
• Renal failure;

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63
Q

Time of flight technique
• Signal is related to flow phenomenon
• Noninvasive
• No contrast

A

Magnetic Resonance Angiography

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64
Q

MRA Application

A

Stenosis
• Thrombosis
• Dissections
• Aneurysms

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65
Q

CE MRA

A

• CE - evaluation following intervention for aneurysm, cerebrovascular malformations (AVM)

• CE MRA - evaluate neck vasculature

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66
Q

Evaluate for patency of dural venous sinuses in venous sinus stenosis or thrombosis

A

Magnetic Resonance Venography

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67
Q

Use of magnetic resonance for localization of cerebral activation

A

Functional MRI

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68
Q

• Used to obtain functional information by visualizing cortical activity

A

Functional MRI

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69
Q

• Detects subtle changes in blood flow/blood oxygenation in response to stimuli or actions

A

Functional MRI

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70
Q

Clinical application of functional MRI

A

• Cortical mapping of known cognitive and motor functional units
• Presurgical and pretherapeutic planning

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71
Q

MRI technique that measures water molecule diffusion and its direction

A

Diffusion Tensor Imaging

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72
Q

Diffusion Tensor Imaging aka

A

Diffusion tractography

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73
Q

map of neural connections

A

Human connectome

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74
Q

Deduce axonal fiber orientation and create 3D color coded maps of white matter tracts

A

Diffusion Tensor Imaging

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75
Q

L to R

A

Red

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76
Q

A to P

A

Green

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77
Q

S to I

A

Blue

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78
Q

Diffusion Tensor Imaging clinical application

A

Asses the integrity of white matter tracts
• Presurgical and pretherapeutic planning

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79
Q

Used as a problem solving technique in attempt to differentiate lesions

A

MR Spectroscopy (MRS)

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80
Q

Relative amplitude of resonance peaks reflects the relative concentrations of metabolites

A

MR Spectroscopy (MRS)

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81
Q

Tumor recurrence vs radiation necrosis

A

Tumor recurrence

(higher choline to creatine ratio)

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82
Q

signify normal neuronal tissue / neuronal integrity
• Decreased in destructive lesions and if there is a decrease in density of neurons

A

N-acetylaspartate (NAA)

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83
Q

signify energy stores

A

Creatine

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84
Q

signify components of the cell membrane and myelin / membrane turnover
• Increased in rapidly dividing tumors

A

Choline

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85
Q

signify anaerobic metabolism

86
Q

marker of astrocytes/astrogliosis seen in
MS

A

Inositol/myoinositol

87
Q

Quantifying blood flow through biologic tissues

Cerebral blood volume, cerebral blood flow and mean transit time

A

MR Perfusion Imaging

88
Q

MR Perfusion Imaging Clinical Application

A

• 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
Q

PET meaning

A

Positron Emission Tomography

90
Q

SPECT meaning

A

Single -Photon Emission
Computed Tomography (SPECT)

91
Q

Molecular imaging used to better understand the biochemical processes that underlie disease

A

PET and SPECT

92
Q

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

A

PET and SPECT

93
Q

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 =

A

Radioligand

94
Q

• Real-time, noninvasive, comprehensive and affordable
• Repeatable, portable
• Harmless

A

Neurovascular Ultrasound

95
Q

Neurovascular Ultrasound

Types

A

Extracranial ultrasound
Transcranial ultrasound

96
Q

Example of extracranial ultrasound

A

(duplex ultrasound or color doppler)

97
Q

Transcranial ultrasound examples

A

(transcranial doppler)

98
Q

Screening extracranial carotid and vertebral arteries for atherosclerosis

A

Extracranial Ultrasound

99
Q

Real-time imaging of anatomy, physiology (hemodynamics) and pathophysiology of extracranial circulation

A

Extracranial ultrasound

100
Q

Carotid imaging for detection of carotid stenosis, assessment after carotid surgery or stenting

A

Extracranial Ultrasound

101
Q

Carotid plaque size, morphology and carotid intima-media thickness

increased risk of stroke

A

Plaque surface irregularity

102
Q

increased risk of stroke or MI

A

Echoluscent carotid plaque (soft)

103
Q

lower risk but may be a marker of presence of active plaque in other vascular beds

A

Echodense carotid plaque (calcified)

104
Q

Indications for Extracranial Ultrasound Examination (Carotid Artery Ultrasound)

A

• 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
Q

Noninvasive ultrasound technology that monitors blood flow velocity and blood flow direction in large intracranial arteries

A

Intracranial Ultrasound (Transcranial Doppler or TCD)

106
Q

Clinical application of Intracranial ultrasound

A

• 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
Q

Limitations of Intracranial ultrasound

A

• Operator dependent
• 10-15% rate of inability to perform TCD due to inadequate windows
• Limited to large cerebral arteries

108
Q

Ultrasound in babies

Transducer placed over

A

open fontanelles or thin calvarium

109
Q

Indications for ultrasound for babies

A

Intracerebral and subdural hemorrhages, mass lesions, congenital defects

110
Q

INR Meaning

A

Interventional Neuroradiology

111
Q

ESNR Meaning

A

Endovascular Surgical
Neuroradiology

112
Q

• Invasive, diagnostic and therapeutic interventions

A

Interventional Neuroradiology
(INR) or Endovascular Surgical
Neuroradiology (ESNR)

113
Q

High resolution images of extracranial and intracranial vasculature

A

Cerebral Angiography

114
Q

Accessing the femoral nerve and threading a catheter into the precerebral vessels

A

Cerebral Angiography

115
Q

Gold standard for viewing cerebral blood vessels

A

Cerebral Angiography

116
Q

soft tissue is eliminated from image leaving only the contrast enhanced vasculature (DSA)

A

Digital subtraction process

117
Q

Cerebral Angiography

Visualization of cerebral and SC vessels to a resolution of- lumen diameter

118
Q

Advantages of Cerebral Angiography

A

Improved temporal resolution
• Functions as both diagnostic and therapeutic

119
Q

Indications for cerebral angiography

A

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
Q

Possible complication for cerebral angiography

A

Artery puncture
• Dislodged plaque - cerebral or systemic ischemic lesions
• Dissection
• Thrombus formation over catheter tip
• Vasospasm
• Disruption of BBB

121
Q

• Measure spontaneous electrical activity generated by neural structures
• Functional assessment of CNS
• Waveforms

A

Electroencephalography (EEG)
Evoked Potentials (EP)

122
Q

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

A

Electroencephalography (EEG)

123
Q

Electroencephalography

Cortical neurons are highly influenced and synchronized by

A

Thalamus and higher brainstem reticular formation

124
Q

Eeg

Each channel represents the difference in electrical potential between the electrodes

A

Positive (downward) and negative (upward)
strokes

125
Q

Varies with state of arousal and age
• Wakefulness - alpha rhythm

A

Electroencephalography (EEG)

126
Q

EEG Activation procedures

A

• Hyperventilation
• Flashes of light (photic stimulation)
• Drowsy states

127
Q

EEG

Clinical Applications

A

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
Q

epileptiform discharges (spikes, polyspikes, sharp waves, spike and slow waves); localization and type of discharge helps identify a specific syndrome

129
Q

toxic, metabolic, diffuse hypoxic-ischemic and other global injuries to the brain result in generalized nonspecific EEG changes

A

Diffuse brain dysfunction or injury

130
Q

Potentials generated by the nervous system in response to stimuli

A

Evoked potentials

131
Q

• 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

A

Evoked Potentials

132
Q

• Dysfunction of sensory or motor pathways due to disease or injury leads to increased waveform latency

A

Evoked Potentials

133
Q

• Complete interruption of conduction or destruction of the neural generators results in the absence of wave forms

A

Evoked Potentials

134
Q

Type of evoked Potentials

A

Somatosensory
Visual
Motor
Brainstem Auditory

135
Q

Elicited by light electrical stimulation of peripheral nerves and reflect sequential activation of structures along sensory pathway (DCML)

A

Somatosensory Evoked Potentials (SSEP)

136
Q

Reveal dysfunction in the sensory pathway that is not clinically apparent
• Capacity to localize a lesion

A

Somatosensory Evoked Potentials (SSEP)

137
Q

Obtained by stimulation with an alternating checkerboard pattern of black and white squares (changes color at regular frequency)

A

Visual Evoked Potentials (VEPs)

138
Q

Visual Evoked Potentials (VEPs)

Produces an occipital positive response with mean latency of

139
Q

• 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

A

Visual Evoked Potentials (VEPs)

140
Q

Auditory stimulus (clicks) delivered to one ear, recorded through scalp electrodes and superimposed on each other

A

Brainstem Auditory Evoked Potentials (BAER)

141
Q

Brainstem Auditory Evoked Potentials (BAER)

Consists of

A

7 waveforms
• I - peripheral portion of auditory nerves
• Ill - superior olivary complex
• V - inferior colliculus

142
Q

• 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

A

Brainstem Auditory Evoked Potentials (BAER)

143
Q

Tests integrity of motor pathways

A

Motor Evoked Potentials

144
Q

Motor Evoked Potentials

Elicited by

A

transcranial magnetic stimulation of primary motor cortex

145
Q

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

A

Nerve Conduction Studies (NCS)

146
Q

• Measure speed and strength of an electrical impulse conducted along a peripheral nerve

A

Nerve Conduction Studies (NCS)

147
Q

Nerve Conduction Studies (NCS)

SNAP waveform produced by

A

large la axons

148
Q

recording electrodes over motor endplate region of an innervated muscle

A

Motor nerves

149
Q

capture the electrical potential generated by
depolarization of the muscle = CMAP

A

Recording electrodes

150
Q

summated number of responsive axons

151
Q

time difference between the stimulus and the waveform onset; measure of nerve speed

A

Distal/onset latency

152
Q
  • latency and distance between stimulus and recording electrode; maximal velocity propagation of action potentials in largest and fastest conducting fibers
A

Conduction velocity

153
Q

depends on intact myelinated nerve = rapid action potential propagation

A

• Latency and conduction velocity

154
Q

depends on the number of functioning axons within the nerve

155
Q

Slowing of CV and prolonged latency =

A

demyelination

156
Q

• Decreased SNAP/CMAP amplitude =

A

axonal loss

157
Q

Information about the proximal segments of a nerve, including the spinal roots

A

Late responses

158
Q

submaximal stimulation of mixed nerves induces a muscle contraction after a latency longer than the direct motor response

159
Q

Describe H Reflex

A

• 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
Q

supramaximal stimulus of a mixed nerve or pure motor nerve

A

F response

161
Q

F Response description

A

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
Q

Needle electrode is inserted into muscle which is activated by voluntary contraction at different levels of effort

A

Needle Electromyography

163
Q

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

A

Needle Electromyography

164
Q

primarily determined by number of activated MUPs and their firing rates

165
Q

Insertional and spontaneous activity, MUP Configuration, recruitment

166
Q

Needle EMG

Insertional activity

A

brief burst of electrical activity provoked by EMG
needle as it moves through the muscle

167
Q

Normal resting muscle is

A

Electrically silent

168
Q

Needle EMG

spontaneous activity

A

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
Q

destruction of muscle fiber; reduced number of MUPs, short duration, low amplitude and polyphasic; high pitched cracking sound like rain fall on tin roof

A

Myopathies

170
Q

high amplitude, long duration, polyphasic MUPs (chronic neurogenic injury)

A

Reinnervation

171
Q

reduced number but normal MUPs

A

Denervation

172
Q

Abnormal EMG

A

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
Q

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

A

• Repetitive Nerve Stimulation (RNS)

174
Q

• Repetitive Nerve Stimulation (RNS)

Trains of — waveforms are evaluated for decrease in area and amplitude

175
Q

• postsynaptic NMJ dysfunction
• decremental responses

A

Myasthenia gravis

176
Q

• A single muscle fiber action potential is measured

A

Single Fiber EMG (SFEMG)

177
Q

interval between stimulus and response varies with each stimulus

178
Q

In NMJ dysfunction

A

Jitter inc

179
Q

Uses light scattering to produce cross sectional images of the retina allowing evaluation of the different layers

A

Optical Coherence Tomography (OCT)

180
Q

lights of varying intensities and sizes appearing in different areas of the visual field while patient fixates on a spot

181
Q

Visual fields

182
Q

Color vision

A

Ishihara plate

183
Q

Visual Acuity

A

Sneklen Chart, E Chart

184
Q

plots the threshold of hearing in decibels with frequencies 8-
125dB
• N = better than 15 dB

185
Q

BAER Meaning

A

Brainstem auditory evoked respons

186
Q

uses electrodes to record eye movements, supplemented by VNG where goggles with infrared cameras track eye movement

A

Electronystagmography/Videonystagmo graphy

187
Q

saccade velocity and accuracy and latency along with smooth pursuit and optokinetic nystagmus
• Evaluation for spontaneous nystagmus

A

Ocular motor testing

188
Q

Evaluation for spontaneous nystagmus
• Positional testing with Dix Hallpike
• Caloric testing

A

Electronystagmography/Videonystagmo graphy

189
Q

Neuropsychological Evaluation

A

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
Q

Tool for evaluating or quantifying the effects of disease on cognition and behavior
• Serial evaluations may show change with time
• Assess area of competence

A

Neuropsychological Evaluation

191
Q

Neuropsychological Evaluation used in

A

Used in:
• Dementia
• Epilepsy
• Psychiatric conditions
• Learning disability

192
Q

Indications of lumbar puncture

A

• 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
Q

Lumbar Puncture safety concern

A

• Possibility of cerebellar or transtentorial herniation in patients with very high CSF pressure esp if from intracranial mass lesion

194
Q

Lumbar puncture steps

A

• 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
Q

Lumbar puncture most common cmplication

A

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
Q

Position & tool for CSF Analysis

A

Patient in lateral decubitus position
• Manometer

197
Q

CSF pressure adult

A

100-180mmH20;

198
Q

CSF Pressure children

A

30 - 60mmH20

199
Q

Inc ICP

A

• > 200mmH20

200
Q

Intracranial Hypotension

A

• < 50mmH20

201
Q

(Froin syndrome) - high CSF protein due to block in CSF flow

A

Yellow and clots readily due to fibrinogen

202
Q

Opaque haziness

A

pleocytosis (increased WBC)

203
Q

Hazy pink - red - blood

A

(bloody tap vs SAH)

204
Q

Acellular

A

(0-5 lymphocytes per cubic mm)

205
Q

Proteins

A

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
Q

CSFelectrophoresis

A

• Albumin, pre-albumin, globulin fractions, immunoglobulin (IgG major Ig in CSF)

207
Q

Glucose

A

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
Q

bacterial, tuberculous, fungal meningitis (active metabolism)

A

• Hypoglycorrhachia with pleocytosis

209
Q

Serologic and Virologic Tests

A

VDRL, RPR - neurosyphilis
• PCR for herpes virus, CMV, TB
• 14-3-3 - CJD

210
Q

Brain Biopsy

A

Mass lesions
• Stereotactic guided biopsy
• Frozen sections

211
Q

Muscle Biopsy

A

Neurogenic vs myogenic disorders
• Moderately affected muscles

212
Q

Nerve biopay

A

Mostly used: sural nerve
• Clinical Applications:
• Vasculitis
• Sarcoid neuropathy
• Amyloidosis
• Leprous neuropathy
• Other peripheral neuropathies

Medsurg (9 decks)

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