ASET CNIM Cards Exam Questions with Correct Answers Graded A+
Which nerve should be stimulated for lower limb SSEP as recommended by American Clinical
Neurophysiology Society guidelines for short-latency SSEP? - Answers Posterior Tibial Nerve
Which nerve should be stimulated for upper limb SSEP as recommended by American Clinical
Neurophysiology Society guidelines for short-latency SSEP? - Answers Median Nerve
The active electrode is usually placed on the scalp 2cm behind _____ for lower limb SSEP - Answers
Vertex (at Cz')
The warning criteria for SSEP changes have been generally accepted as - Answers 50% decrease in
amplitude and 10% increase in latency
Electrode placement on the scalp is based on - Answers 10-20 System
Central Conduction Time (CCT) for median nerve is calculated between which peaks? - Answers P14-N20
Peripheral Conduction Time (PCT) for median nerve is calculated between which peaks? - Answers EP-
P14
Central Conduction Time (CCT) for posterior tibial nerve is calculated between which peaks? - Answers
LP-P37
Peripheral Conduction Time (PCT) for posterior tibial nerve is calculated between which peaks? -
Answers PF-LP
Peripheral response (PF) to the first response from cord (LP)
SSEP is not recordable when cerebral perfusion drops below: - Answers 15cc/min/100 grams of tissue
The normal amplitude of SSEP responses recorded from scalp is approximately: - Answers 0.1 microV to
10 microV
If there is a sudden loss of ipsilateral Erb's point and contralateral N20 response, what is the first step
for troubleshooting? - Answers Check arm positioning
Latency and/or amplitude changes in SSEP responses can result from: - Answers Anesthesia,
Hypothermia, Surgical manipulation, Technical failure
The N20 response is generated from which structure? - Answers Somatosensory cortex (contralateral to
the stimulation side)
The P14 response is generated from which structure? - Answers Caudal medial lemniscus
The N34 subcortical response is a near-field or far-field response? - Answers far-field response
Lumbar potential (LP) is a stationary (non-propagated) potential
,-true
-false - Answers True
The most reliable criteria for SSEP abnormality is: - Answers Absence of the obligatory waveforms
Prolongation of the interpeak latencies
The N18 subcortical response is a near-field or far-field response? - Answers Far-field response
After stimulation of the median nerve at the wrist, the response recorded at the Erb's point consists of: -
Answers An orthodromic sensory and antidromic motor action potentials
Obligatory waves of the posterior tibial nerve (PTN) are: - Answers PF, LP, P31, N34, P37
Obligatory waves of the median nerve (MN) are: - Answers N9, N13, P14, N18, N20
What is the location of injury if there is a loss of cortical SSEP responses but intact Erb's point responses?
- Answers Brainstem / Thalamus
Which of the following sensations are not transferred via dorsal column?
-proprioception
-stereognosis
-temperature - Answers temperature
What is the blood supply of cortical responses elicited by median nerve stimulation? - Answers Middle
Cerebral Artery (MCA)
Ohm's law is mathematically expressed as:
- V=I/R
- V=IR
- I=VR
- R=VI - Answers V=IR
Good insulating materials that inhibit the current flow are: - Answers Glass, rubber, wood
What is the maximum allowable chassis leakage current? - Answers Should be less than 300microA rms
with ground open
What is the maximum allowable leakage current through patient leads to ground with 120VAC applied?
- Answers 10microA rms
, In order to minimize filter-induced phase shift, the ratio of high-to-low frequency filter should be at
least? - Answers 100:1
A large current passing from an external surface to another is known as: - Answers Macroshock
A very low current as small as 10 microvolts that can be lethal to the patient if it passes through the
heart is known as: - Answers Microshock
A band-stop filter is also called: - Answers 60Hz notch filter
What is the electrical line frequency in the operating rooms in the USA? - Answers 60Hz
The inter stimulus interval (ISI) of a 40Hz stimulation will be: - Answers 25 milliseconds
Unequal electrode impedances may result in: - Answers increased noise
The electrical charge stored by a capacitor is known as: - Answers capacitance
Opposition to change in current flow is known as: - Answers Inductance
Subdermal electrodes made of platinum have what advantage? - Answers inert stability during
stimulation and MRI compatible
The impedances of subdermal needle electrodes are typically higher than scalp electrodes
-True
-False - Answers True
Where is the best place to put a ground electrode in order to reduce any stimulation artifact? - Answers
Between stimulation and recording electrodes
The cortical grid is made of what type of metal? - Answers Platinum
What is the electrical line frequency in the operating rooms in Europe? - Answers 50Hz
Electrocochleogram (ECochG) consists of combinations of which responses? - Answers Cochlear
microphonic (CM), Summating Potentials (SP), and Auditory nerve compound action potentials
Click stimulations should be delivered unilaterally or bilaterally? - Answers unilaterally
What is the recommended bandpass filter settings for BAEP recordings? - Answers 10-30Hz to 2500-
3000Hz
The filter roll-off for BAEP should not exceed what values for low and high frequency filters? - Answers
12bB/octave for low frequency filter
24dB/octave for high frequency filter
Which nerve should be stimulated for lower limb SSEP as recommended by American Clinical
Neurophysiology Society guidelines for short-latency SSEP? - Answers Posterior Tibial Nerve
Which nerve should be stimulated for upper limb SSEP as recommended by American Clinical
Neurophysiology Society guidelines for short-latency SSEP? - Answers Median Nerve
The active electrode is usually placed on the scalp 2cm behind _____ for lower limb SSEP - Answers
Vertex (at Cz')
The warning criteria for SSEP changes have been generally accepted as - Answers 50% decrease in
amplitude and 10% increase in latency
Electrode placement on the scalp is based on - Answers 10-20 System
Central Conduction Time (CCT) for median nerve is calculated between which peaks? - Answers P14-N20
Peripheral Conduction Time (PCT) for median nerve is calculated between which peaks? - Answers EP-
P14
Central Conduction Time (CCT) for posterior tibial nerve is calculated between which peaks? - Answers
LP-P37
Peripheral Conduction Time (PCT) for posterior tibial nerve is calculated between which peaks? -
Answers PF-LP
Peripheral response (PF) to the first response from cord (LP)
SSEP is not recordable when cerebral perfusion drops below: - Answers 15cc/min/100 grams of tissue
The normal amplitude of SSEP responses recorded from scalp is approximately: - Answers 0.1 microV to
10 microV
If there is a sudden loss of ipsilateral Erb's point and contralateral N20 response, what is the first step
for troubleshooting? - Answers Check arm positioning
Latency and/or amplitude changes in SSEP responses can result from: - Answers Anesthesia,
Hypothermia, Surgical manipulation, Technical failure
The N20 response is generated from which structure? - Answers Somatosensory cortex (contralateral to
the stimulation side)
The P14 response is generated from which structure? - Answers Caudal medial lemniscus
The N34 subcortical response is a near-field or far-field response? - Answers far-field response
Lumbar potential (LP) is a stationary (non-propagated) potential
,-true
-false - Answers True
The most reliable criteria for SSEP abnormality is: - Answers Absence of the obligatory waveforms
Prolongation of the interpeak latencies
The N18 subcortical response is a near-field or far-field response? - Answers Far-field response
After stimulation of the median nerve at the wrist, the response recorded at the Erb's point consists of: -
Answers An orthodromic sensory and antidromic motor action potentials
Obligatory waves of the posterior tibial nerve (PTN) are: - Answers PF, LP, P31, N34, P37
Obligatory waves of the median nerve (MN) are: - Answers N9, N13, P14, N18, N20
What is the location of injury if there is a loss of cortical SSEP responses but intact Erb's point responses?
- Answers Brainstem / Thalamus
Which of the following sensations are not transferred via dorsal column?
-proprioception
-stereognosis
-temperature - Answers temperature
What is the blood supply of cortical responses elicited by median nerve stimulation? - Answers Middle
Cerebral Artery (MCA)
Ohm's law is mathematically expressed as:
- V=I/R
- V=IR
- I=VR
- R=VI - Answers V=IR
Good insulating materials that inhibit the current flow are: - Answers Glass, rubber, wood
What is the maximum allowable chassis leakage current? - Answers Should be less than 300microA rms
with ground open
What is the maximum allowable leakage current through patient leads to ground with 120VAC applied?
- Answers 10microA rms
, In order to minimize filter-induced phase shift, the ratio of high-to-low frequency filter should be at
least? - Answers 100:1
A large current passing from an external surface to another is known as: - Answers Macroshock
A very low current as small as 10 microvolts that can be lethal to the patient if it passes through the
heart is known as: - Answers Microshock
A band-stop filter is also called: - Answers 60Hz notch filter
What is the electrical line frequency in the operating rooms in the USA? - Answers 60Hz
The inter stimulus interval (ISI) of a 40Hz stimulation will be: - Answers 25 milliseconds
Unequal electrode impedances may result in: - Answers increased noise
The electrical charge stored by a capacitor is known as: - Answers capacitance
Opposition to change in current flow is known as: - Answers Inductance
Subdermal electrodes made of platinum have what advantage? - Answers inert stability during
stimulation and MRI compatible
The impedances of subdermal needle electrodes are typically higher than scalp electrodes
-True
-False - Answers True
Where is the best place to put a ground electrode in order to reduce any stimulation artifact? - Answers
Between stimulation and recording electrodes
The cortical grid is made of what type of metal? - Answers Platinum
What is the electrical line frequency in the operating rooms in Europe? - Answers 50Hz
Electrocochleogram (ECochG) consists of combinations of which responses? - Answers Cochlear
microphonic (CM), Summating Potentials (SP), and Auditory nerve compound action potentials
Click stimulations should be delivered unilaterally or bilaterally? - Answers unilaterally
What is the recommended bandpass filter settings for BAEP recordings? - Answers 10-30Hz to 2500-
3000Hz
The filter roll-off for BAEP should not exceed what values for low and high frequency filters? - Answers
12bB/octave for low frequency filter
24dB/octave for high frequency filter
