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CONTENT OUTLINE
I. BASIC SCIENCE
AND
INSTRUMENTATIO
N
A. Current Flow
1. Conduction and
Insulation
2. Impedance
3. Resistance
4. Capacitance and
Inductance
B. Instrumentation
1. Differential
Amplifiers
a. Input Impedance
b. Common Mode
Rejection
c. Polarity
d. Gain/Sensitivity
e. Other
2. Filters and Their
Effects
a. Low Frequency
Filter
b. High Frequency
Filter
c. Filter Slopes
d. Digital Filter
e. Notch (60 Hz)
Filter
3. Analog to Digital
Conversion
a. Sampling Rate
b. Nyquist
Frequency Aliasing
c. Horizontal
Resolution
1. Analysis Time
2. Dwell Time
d. Vertical
(amplitude)
Resolution
1. Size of A-D
Converter
2. Amplifier
Sensitivity
3. Number of
Stimuli
4. Signal Averaging
5. Signal-to-Noise
Ratio
6. Display Sensitivity
7. Artifact Rejection
8. Stimulus and
Averaging Onset
a. Pre-stimulus
(negative) Delay
b. Post-stimulus
(positive) Delay
9. Simultaneous
Averaging
a. Synchronous
b. Asynchronous
c. Multiple Time
Bases
C. Anatomy of IOM
Systems
1. Brain
2. Brain Stem
a. Vascular Anatomy
b. Neuroanatomy
3. Cranial Nerves
a. Sensory
b. Motor
4. Spinal Cord
a. Bony Structures
b. Posterior Columns
c. Motor Tracts
d. Spinal Circulation
e. Cauda Equina
f. Dermatomal
Distribution
5. Peripheral Nerves
6. Evoked Potential
Generators
a. BAEPs
b. SSEPs
c. Cranial Nerve
EMG
d. Spinal Responses
D. Basic
Neurophysiology
1. Membrane Potential
2. Action Potential
3. Synaptic Potential
a. Inhibitory
b. Excitatory
4. Stationary Potential
5. Propagated
Potential
6. Cortical/Subcortical
Potential
7. Near-Field/Far-Field
Potential
8. Neurons
9. Neurotransmitters
a. Inhibitory
b. Excitatory
10. Dipoles
II. RECORDING
CONCEPTS
AND
PREOPERATIVE
FACTORS
A. Electrodes
1. Types of Electrodes
a. Surface
b. Subdermal
c. Spinal (Epidural)
d. Cortical Grid
e. Other
2. Location and
Measurement
3. Application
a. Security
b. Duplicate Set
4. Impedance
Measurement
B. Operation of
Equipment
1. Amplifiers
2. Averager
3. Audiometer
4. Auditory Stimulator
a. Measurements of
Click Intensity
1. Calibration
2. Hearing Level
(dBHL)
9
3. Sensation Level
(dBSL)
4. Peak-Equivalent
Sound Pressure
Level (dB pe
SPL)
b. Masking
c. Types of
Transducer
1. Standard
Audiologic
2. Tubal Inserts
With Stimulus
Delay
3. Small Inserts
Without Delay
4. Other
5. Current Stimulator
a. Adequacy of
Stimulus Intensity
b. Types
1. Constant
Current
2. Constant
Voltage
c. Site of Stimulation
1. Transdermal
2. Near Nerve
Needle
3. Direct Cranial
Nerve
4. Spinal Cord
5. Cortical
d. Electrodes
1. Types
2. Monopolar vs
Bipolar
e. Stimulation Issues
1. Impedance of
Tissue/
Shunting of
Current
2. Ohm's Law and
Application
3. Neurotoxicity
4. Current Density
5. Polarity
f. Stimulus
Parameters
1. Duration
2. Rate
3. Monophasic vs
Biphasic Pulse
C. BAEPs
1. Nonpathologic
Factors
a. Filter Effects
b. Click Intensity
c. Click Polarity
d. Click Rate
e. Masking
f. Other
2. Pathologic Factors
a. Hearing Deficits
1. Cochlear
2. Retrocochlear
b. Lesions
c. Other
3. Montages
4. Obligate
Components and
Measures
5. Criteria for
Abnormality
D. SSEPs
1. Nonpathologic
Factors
a. Motor/Sensory
Threshold
b. Adequacy of
Peripheral Nerve
Response
c. Equalizing
Peripheral Nerve
Response
d. Filter Effects
e. Limb Temperature
and Length
2. Pathologic Factors
a. Peripheral
Neuropathy
b. Other
3. Montages
4. Obligate
Components and
Measures
5. Criteria for
Abnormality
E. Surgical Procedures
and Appropriate
Monitoring Procedures
1. Posterior Fossa
a. BAEPs
b. MN-SSEPs
c. Cranial Nerves
d.
Electrocochleograms
2. Carotid Artery
a. MN-SSEPs
b. EEG
c. TCD
d. Cerebral Oximetry
3. Spinal Cord Lesions
a. MN-SSEPs
b. PTN-SSEPs
c. Other
4. Scoliosis
a. PTN-SSEPs
b. CPN-SSEPs
5. Other Spine
Procedures
6. Otolaryngology
a. BAEPs
b. Facial Nerve
c.
Electrocochleograms
d. Other
7. Functional Mapping
a. Sensory
b. Motor
8.
Electrocorticography
& EEG
9. Other
F. Preoperative
Baseline
1. BAEPs
2. SSEPs
3. Multi-modality
4. EEG
5. Other
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III.
INTRAOPERATIVE
MONITORING
A. Technologist's Role
in the OR
1. Relationship With
Team
2. Data Description
and
Documentation
B. Methods of
Recording
1. Scalp-to-Scalp
2. Scalp-toNoncephalic
3. Spinal
a. Bipolar vs
Referential
b. Sites
1. Interspinous
Ligament
2. Spinous Process
3. Epidural
4. Cranial NerveSupplied Muscles
5. Peripheral Nerves
6. Motor Nerve
Conduction
7. Myotomal
a. Cervical
b. Thoracic
c. Lumbar
d. Sacral
C. Surgical
Instrumentation and
Equipment
1. Neurosurgical
2. Orthopaedic
3. Otolaryngology
4. Others
D. Induction and
Intrasurgical
1. Patient Positioning Routing of
Electrodes/ Cables
2. Post-Anesthesia
and
Post-Positioning
Recording
3. Use of Input vs
Averaged Data
4. Criteria for
Abnormality
5. Trending of Data
a.Latencies/Interpeak
Intervals/Amplitudes
b. Processed EEG
1. Condensed
Density
Spectral Array
2. Spectral Edge
6. Train of Four
Stimulation
a. Recording
b. Stimulation
c. Uses
E. Factors Affecting
Waveform Resolution
1. Physiologic
a. Blood Pressure,
Perfusion
b. Temperature
c. ICP
d. Oxygenation
e. Ventilation
f. Metabolites,
Electrolyttes
g. Others
2. Pharmacologic
a. Types of
Anesthetic
Agents
1. Intravenous
Agents
a. Opiod
Agents
b. Ketamine
2. Inhalational
Agents
a. Halogenated
b. Nitrous
3. SedativeHypnotic Drugs
a. Barbiturates
b. Benzodiazapi
nes
c. Etomidate
d. Propofol
e. Droperidol
4. Neuromuscular
Blocking
Agents
a. Depolarizing
b. NonDepolarizing
5. Regional
Anesthesia
b. Measures of
Concentration
c. Rate of
Administration
1. Constant
Infusion
2. Bolus
3. Structural
a. Traction on
Neural
Structures
b. Vascular
Compromise
c. Coagulation
and Drilling
4. Technical
a. Stimulus
Parameters
b. Electrodes
c.Recording
Parameters
F. Facial Nerve
Stimulation and
Recording
1. Spontaneous
Activity
2. Compound Muscle
Action Potentials
3. Effects of
Neuromuscular
Blocking Agents
4. Effects of Stimulus
Intensity
5. Amplitude/Intensity
Function
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G. Motor Pathway
Stimulation
1. Uses
2. Stimulators
a. Magnetic
b. Electrical
3. Effects of Various
Factors
a. Halogenated
Agents
b. Neuromuscular
Blocking Agents
c. Stimulus Rate
d. Stimulus Intensity
H. Intraoperative
Monitoring Record
1. Annotating
Changes
a. Blood Pressure
b. Core Temperature
c. Limb Temperature
d. Anesthetic
Agents
e. Instrumentation
Parameters
2. Procedure
Milestones
3. Surgical
Manipulations
4. Monitoring
Feedback
to Surgeons
5. Surgeon Response
IV.SURGICAL
OUTCOMES
A. Preexisting Clinical
Correlates
B. Complications
1. Motor System
2. Sensory System
3. Auditory Pathway
4. Cranial Nerve Palsy
5. Other Neurologic
Deficits
C. Prevention
1. Criteria for Warning
Surgeon
2. Wake-Up Test
V.
TROUBLESHOOTIN
G
A. Basic Concepts
1. Appropriate
Baseline
Responses
2. Communication
with
Surgeon and
Anesthesiologist
3. Systemic vs Local
Effects
a. Effects of
Vascular
Manipulation
b. Effects of
Structural
Manipulation
B. Artifacts
1. Physiologic
a. EMG
b. ECG
c. Other
2. Nonphysiologic
a. 60 Hz
b. Stimulator
c. Electrode
d. OR Equipment
1. Electrocautery Bipolar vs
Monopolar
2. Blood Warmer
3. Humidifier
4. Fluorescent
Lights
5. Microscope
6. Neurosurgical
Devices
7. Pneumatic Drill
8. Cell Saver
9. CUSA
10. BAIR Hugger
e. Other
C. Effects on
Waveform
Resolution
1. Electrocautery
2. Coagulation
3. Drilling
VI. SAFETY ISSUES
A. Infection Control
Standard
1. Universal
Precautions
2. Sterile Techniques
3. Transmission Based
Precautions
4. Electrode Care
5. Equipment Care
B. Electrical Safety
1. Leakage Current
2. Grounding System
3. Line Isolation
Monitor
4. Isolated Inputs
5. Safety Checks
C. Hazards
1. Infections
2. Electrical
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SAMPLE
QUESTIONS
1. Cortical potentials
will be most affected
by which of the
following agents?
1. Narcotics
2. Barbiturates
3. Inhalational
anesthetics
4. Neuromuscular
blockers
2. Which of the
following is a far-field
potential?
1. N20
2. P14
3. Wave I
4. Erb's point
3. Which of the
following is an effect
of using alternating
click polarity?
1. Reduces stimulus
intensity
2. Minimizes stimulus
artifact
3. Increases
amplitude of wave I
4. Improved signal to
noise ratio
4. ANKYLOSIS
1. Foot drop
2. Wrist drop
3. Fused joint
4. Arterial occlusion
5. Grounding the
stimulated limb during
a SSEP procedure
decreases
1. stimulus artifact.
2. stimulus intensity.
3. stimulating
electrode impedances.
4. spread of
stimulating current.
6. What is the
MAXIMUM acceptable
chassis leakage
current?
1. 1 µA
2. 10 µA
3. 100 µA
4. 1000 µA
Answers to sample
questions: 1.3, 2.2,
3.2, 4.3, 5.1, 6.3
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