CNIM Instrumentation Exam Questions
and Answers All Correct
A constant current stimulator
A- Varies the output voltage in order to maintain a certain current level
B- Maintains a current level of 5 mA
C- Maintains a constant voltage of 250 volts
D- Varies the current level in order to maintain a certain voltage level - Answer-A-
Varies the output voltage in order to maintain a certain current level
In a somatosensory EP, how will changing the high frequency filter from 30 kHz to 1KHz
affect the cortical responses
A- Cause a phase lag and appear to prolong the latency
B- Increase the amplitude of the responses
C- Decrease the amplitude of the responses
D- Cause a phase lead and appear to shorten the latency - Answer-A- Cause a phase
lag and appear to prolong the latency
What is the required CMRR for an evoked potential system?
A- 80 dB
B- 100 dB
C- 60 dB
D- 120 dB - Answer-A- 80 dB
What is the resulting waveform from a differential amplifier? Choose the correct answer.
A- An upward signal into the second input will be displayed as an upward peak
B- An upward signal into the first input will be displayed as a upward peak
C- A downward signal into the first input will be displayed as a downward peak
D- A downward signal into the second input will be displayed as an upward peak -
Answer-A- An upward signal into the second input will be displayed as an upward peak
When an amplifier dwell time is too long, which of the following phenomenon can occur?
A- Clipping
B- Aliasing
C- Attenuation
D- Ringing - Answer-B- Aliasing
What is the voltage delivered to the patient if the constant current stimulator is set to 20
mA and the electrode impedance is 2 K ohms?
A- 100 V
,B- 20 V
C- 40 V
D- 10 mV - Answer-C- 40 V
What is the frequency of a waveform that has a wavelength of 10 mS?
A- 100 Hz
B- 1 KHz
C- 10 Hz
D- 10 KHz - Answer-A- 100 Hz
A unit of resistance is symbolized by
A- A
B- ohms
C- E
D- micro - Answer-B- ohms
The capacity to resolve amplitudes of 256 discrete steps would require an 8 bit A to D
converter. This can be represented by:
A- 8
B- 8/256
C- 256
D- 2^8 - Answer-D- 2^8
What is the minimum required bandpass for an EP system?
A- 1 - 1000 Hz
B- 0.1 ‐ 5000 Hz
C- 30 ‐ 1500 Hz
D- 1 Hz - 20 KHz - Answer-B- 0.1 ‐ 5000 Hz
The gain of an amplifier, set to give an output signal of 1 volt for an input signal of 10
microV, is
A- 100,000
B- 10,000
C- 100
D- 1,000 - Answer-A- 100,000
A 100 mS epoch is recorded with a 10 mS post ‐ stimulus triggering. Which of the
following best describes the resulting sweep?
A- A 100 mS sweep starting 10 mS after the stimulus
B- A 90 mS sweep starting 10 mS after the stimulus
C- A 100 mS sweep starting 10 mS prior to the stimulus
D- A 110 mS sweep starting 10 mS prior to the stimulus - Answer-A- A 100 mS sweep
starting 10 mS after the stimulus
SSEP recordings typically require a bandpass of
A- 1000 Hz to 5,000 Hz
, B- 30 Hz to 3,000 Hz
C- 100 Hz to 1,000 Hz
D- .5 Hz to 200 Hz - Answer-B- 30 Hz to 3,000 Hz
To accurately represent the amplitude of an EP waveform, a match must be made
between the
A- dwell time and sampling rate
B- signal size and the vertical capacity of the digitizer
C- high‐frequency noise and smoothing operation of the instrument
D- horizontal resolution and signal size - Answer-B- signal size and the vertical capacity
of the digitizer
In selecting the horizontal parameters of analysis, the
A- sampling rate should be the equivalent of the highest frequency in the signal
B- analysis period should be at least twice the Nyquist frequency
C- sampling rate should be at least two times greater than the highest frequency in the
signal
D- analysis period should approach the Nyquist frequency - Answer-C- sampling rate
should be at least two times greater than the highest frequency in the signal
The assumption that responses of excessive amplitude are likely to contain artifact
forms the basis for
A- digital filtering
B- artifact rejection
C- dwell time
D- digital averaging - Answer-B- artifact rejection
In a differential amplifier used for intraoperative monitoring, the common mode rejection
of in phase signals is typically
A- 100:1
B- 5:1
C- 10,000:1
D- 500:1 - Answer-C- 10,000:1
A differential amplifier records
A- the second half of the two inputs
B- only the first two inputs
C- the second half of the two inputs
D- the difference between the two inputs - Answer-D- the difference between the two
inputs
The Nyquist frequency is:
A- equal to the sampling rate
B- 1/3 the highest frequency
C- 1/2 the highest frequency
and Answers All Correct
A constant current stimulator
A- Varies the output voltage in order to maintain a certain current level
B- Maintains a current level of 5 mA
C- Maintains a constant voltage of 250 volts
D- Varies the current level in order to maintain a certain voltage level - Answer-A-
Varies the output voltage in order to maintain a certain current level
In a somatosensory EP, how will changing the high frequency filter from 30 kHz to 1KHz
affect the cortical responses
A- Cause a phase lag and appear to prolong the latency
B- Increase the amplitude of the responses
C- Decrease the amplitude of the responses
D- Cause a phase lead and appear to shorten the latency - Answer-A- Cause a phase
lag and appear to prolong the latency
What is the required CMRR for an evoked potential system?
A- 80 dB
B- 100 dB
C- 60 dB
D- 120 dB - Answer-A- 80 dB
What is the resulting waveform from a differential amplifier? Choose the correct answer.
A- An upward signal into the second input will be displayed as an upward peak
B- An upward signal into the first input will be displayed as a upward peak
C- A downward signal into the first input will be displayed as a downward peak
D- A downward signal into the second input will be displayed as an upward peak -
Answer-A- An upward signal into the second input will be displayed as an upward peak
When an amplifier dwell time is too long, which of the following phenomenon can occur?
A- Clipping
B- Aliasing
C- Attenuation
D- Ringing - Answer-B- Aliasing
What is the voltage delivered to the patient if the constant current stimulator is set to 20
mA and the electrode impedance is 2 K ohms?
A- 100 V
,B- 20 V
C- 40 V
D- 10 mV - Answer-C- 40 V
What is the frequency of a waveform that has a wavelength of 10 mS?
A- 100 Hz
B- 1 KHz
C- 10 Hz
D- 10 KHz - Answer-A- 100 Hz
A unit of resistance is symbolized by
A- A
B- ohms
C- E
D- micro - Answer-B- ohms
The capacity to resolve amplitudes of 256 discrete steps would require an 8 bit A to D
converter. This can be represented by:
A- 8
B- 8/256
C- 256
D- 2^8 - Answer-D- 2^8
What is the minimum required bandpass for an EP system?
A- 1 - 1000 Hz
B- 0.1 ‐ 5000 Hz
C- 30 ‐ 1500 Hz
D- 1 Hz - 20 KHz - Answer-B- 0.1 ‐ 5000 Hz
The gain of an amplifier, set to give an output signal of 1 volt for an input signal of 10
microV, is
A- 100,000
B- 10,000
C- 100
D- 1,000 - Answer-A- 100,000
A 100 mS epoch is recorded with a 10 mS post ‐ stimulus triggering. Which of the
following best describes the resulting sweep?
A- A 100 mS sweep starting 10 mS after the stimulus
B- A 90 mS sweep starting 10 mS after the stimulus
C- A 100 mS sweep starting 10 mS prior to the stimulus
D- A 110 mS sweep starting 10 mS prior to the stimulus - Answer-A- A 100 mS sweep
starting 10 mS after the stimulus
SSEP recordings typically require a bandpass of
A- 1000 Hz to 5,000 Hz
, B- 30 Hz to 3,000 Hz
C- 100 Hz to 1,000 Hz
D- .5 Hz to 200 Hz - Answer-B- 30 Hz to 3,000 Hz
To accurately represent the amplitude of an EP waveform, a match must be made
between the
A- dwell time and sampling rate
B- signal size and the vertical capacity of the digitizer
C- high‐frequency noise and smoothing operation of the instrument
D- horizontal resolution and signal size - Answer-B- signal size and the vertical capacity
of the digitizer
In selecting the horizontal parameters of analysis, the
A- sampling rate should be the equivalent of the highest frequency in the signal
B- analysis period should be at least twice the Nyquist frequency
C- sampling rate should be at least two times greater than the highest frequency in the
signal
D- analysis period should approach the Nyquist frequency - Answer-C- sampling rate
should be at least two times greater than the highest frequency in the signal
The assumption that responses of excessive amplitude are likely to contain artifact
forms the basis for
A- digital filtering
B- artifact rejection
C- dwell time
D- digital averaging - Answer-B- artifact rejection
In a differential amplifier used for intraoperative monitoring, the common mode rejection
of in phase signals is typically
A- 100:1
B- 5:1
C- 10,000:1
D- 500:1 - Answer-C- 10,000:1
A differential amplifier records
A- the second half of the two inputs
B- only the first two inputs
C- the second half of the two inputs
D- the difference between the two inputs - Answer-D- the difference between the two
inputs
The Nyquist frequency is:
A- equal to the sampling rate
B- 1/3 the highest frequency
C- 1/2 the highest frequency
