ACNS Guidelines Questions with Verified Correct
Answer
Monitoring physician
Should be licensed in the state and privileged to interpret neurophysiologic testing in the
hospital. They are responsible for interpretation of data.
How many cases is it recommended the online physician monitor at once?
No more than three cases concurrently
What should monitoring system include?
the capacity to:
display raw data and continuous trends
store time/date of recorded waveforms
trigger stim of potentials such as EMG, peripheral or cranial nerve
record free run signals
record technologist's notes with waveform data
retrieve and review recorded data for post-hoc analysis
automatic artifact rejection
remote, real time display of data
Can post-hoc analysis replace real time interpretation by physician?
No
What is the limit on total chassis leakage?
,100 uA
What is the limit on chassis leakage for isolated patient connections?
10 uA
The grounding system should ensure that no voltage greater than ________ can be
measured across an impedance of ______________, typically at _____ Hz, between any
combo of exposed or conductive surfaces or grounding conductors that may be in contact
with patient or personnel.
20 mV rms, 1000 ohms, 60 Hz
How often must IONM systems be inspected?
At least twice a year
True or false: interpreter should be cognizant that changes in data may be just as marked
with hypotension and cardiovascular collapse as with surgical manipulation or
compression of neural pathways
True
True or false: N20 and halogenated inhalational agents can have even more prominent
attenuation effects on lower extremity SSEPs and in young children
True
When are baseline IONM values established?
,Following induction of anesthesia and positioning of patient, and prior to surgical intervention.
Baseline values may need to be reestablished if changes in anesthetic medications or other
physiological parameters occur during the case.
True or false: In cases where it is determined that there is little or no risk to neural
structures during a specific portion of a particular procedure, the interpreting physician
may, in consulation with the surgeon , elect to suspend IONM
true
True or false: In general, surgical injury more often produced waveform amplitude or
morphology changes, than latency prolongation.
True
True or false: Gain should be adjustable in steps of not more than 2.5 to 1
True
Differential input impedance of amplifier must be at least ___________
100 megaOhm
Common mode rejection should be _________
at least 80 dB (10,000:1)
True or false: With filters wide open, the amplifier bandpass measured at the -3 dB points
must be at least 0.1-5,000 Hz. The rolloff slops must be specified.
True
The noise level of the amplifier must not exceed _______
, 2 uV rms with all the inputs connected to neutral and with a bandpass of 0.1-5,000 Hz
Time (horizontal) resolution of the EP system should be ____ us/data point of less
20 us/data point
Amplitude resolution of eight bits or 12 bits at the A-D converted?
eight bits adequate for many applications, but 12 bit converters are preferred because they are
usable across a broader dynamic range
How many addresses of memory should be available for each channel?
500
How many trials should the evoked potential system allow for?
at least 4,000
True or false: excessive analog filtering will alter the latency, amplitude, and morphology of
evoked potential components.
True
True or false: Excessive low-frequency filtering will cause a peak or valley to appear
earlier, leading to falsely normal results.
True (Phase lead)
True or false: Excessive high-frequency filtering will delay (prolong) a peak or valley
leading to a possible falsely abnormal study
True: phase lag
Answer
Monitoring physician
Should be licensed in the state and privileged to interpret neurophysiologic testing in the
hospital. They are responsible for interpretation of data.
How many cases is it recommended the online physician monitor at once?
No more than three cases concurrently
What should monitoring system include?
the capacity to:
display raw data and continuous trends
store time/date of recorded waveforms
trigger stim of potentials such as EMG, peripheral or cranial nerve
record free run signals
record technologist's notes with waveform data
retrieve and review recorded data for post-hoc analysis
automatic artifact rejection
remote, real time display of data
Can post-hoc analysis replace real time interpretation by physician?
No
What is the limit on total chassis leakage?
,100 uA
What is the limit on chassis leakage for isolated patient connections?
10 uA
The grounding system should ensure that no voltage greater than ________ can be
measured across an impedance of ______________, typically at _____ Hz, between any
combo of exposed or conductive surfaces or grounding conductors that may be in contact
with patient or personnel.
20 mV rms, 1000 ohms, 60 Hz
How often must IONM systems be inspected?
At least twice a year
True or false: interpreter should be cognizant that changes in data may be just as marked
with hypotension and cardiovascular collapse as with surgical manipulation or
compression of neural pathways
True
True or false: N20 and halogenated inhalational agents can have even more prominent
attenuation effects on lower extremity SSEPs and in young children
True
When are baseline IONM values established?
,Following induction of anesthesia and positioning of patient, and prior to surgical intervention.
Baseline values may need to be reestablished if changes in anesthetic medications or other
physiological parameters occur during the case.
True or false: In cases where it is determined that there is little or no risk to neural
structures during a specific portion of a particular procedure, the interpreting physician
may, in consulation with the surgeon , elect to suspend IONM
true
True or false: In general, surgical injury more often produced waveform amplitude or
morphology changes, than latency prolongation.
True
True or false: Gain should be adjustable in steps of not more than 2.5 to 1
True
Differential input impedance of amplifier must be at least ___________
100 megaOhm
Common mode rejection should be _________
at least 80 dB (10,000:1)
True or false: With filters wide open, the amplifier bandpass measured at the -3 dB points
must be at least 0.1-5,000 Hz. The rolloff slops must be specified.
True
The noise level of the amplifier must not exceed _______
, 2 uV rms with all the inputs connected to neutral and with a bandpass of 0.1-5,000 Hz
Time (horizontal) resolution of the EP system should be ____ us/data point of less
20 us/data point
Amplitude resolution of eight bits or 12 bits at the A-D converted?
eight bits adequate for many applications, but 12 bit converters are preferred because they are
usable across a broader dynamic range
How many addresses of memory should be available for each channel?
500
How many trials should the evoked potential system allow for?
at least 4,000
True or false: excessive analog filtering will alter the latency, amplitude, and morphology of
evoked potential components.
True
True or false: Excessive low-frequency filtering will cause a peak or valley to appear
earlier, leading to falsely normal results.
True (Phase lead)
True or false: Excessive high-frequency filtering will delay (prolong) a peak or valley
leading to a possible falsely abnormal study
True: phase lag
