CNIM PRACTICE QUESTIONS WITH
CORRECT ANSWERS 100% VERIFIED
2024/2025
Averaging a small amplitude signal, generated as response to a stimulus, that is buried
in noise will result in clarification of the signal of interest if which of these criteria are
met? (select all that apply)
a. the signal of interest (the response being measured) is the same for all repetitions of
the test (same amplitude, morphology and frequency)
b. the signal of interest is time locked to the stimulus, in other words, always at the
same time point relative to another event such as a stimulus
c. noise is different from, uncorrelated to and random compared to the signal of interest
- Answer- all of the above
Due to a smaller surface area, subdermal needle electrodes will have an impedance
that is:
a. improved by cleansing the skin with an abrasive gel before insertion
b. higher than surface electrodes, but usually equal and balanced when all subdermal
needle electrodes are used
c. lower than disk electrodes
d. unbalanced causing increased 60 Hz noise - Answer- b. higher than surface
electrodes, but usually equal and balanced when all subdermal need electrodes are
used
Glucose is monitored (and treated) during surgery because: (select all that apply)
a. glucose produces an intracellular acidosis during ischemia
b. low glucose levels are associated with worsened neurological injury
c. high glucose levels are associated with worsened neurological injury - Answer- all of
the above
In a medical legal case
a. having good supervision will get you off
b. a CNIM certification always protects the technologist from getting sued
c. none of the answers listed are correct
d. your lawyer will get you off
e. demonstrating knowledge of ASET literature will get you off - Answer- c. none of the
answers listed are correct
A stimulus pulse width that would tend to excite a larger population of motor fibers than
sensory fibers is:
a. 1 ms
,b. 0.05 ms
c. 0.5. ms
d. 0.2 ms - Answer- b. 0.05 ms
During a craniotomy for brain surgery which methods are used to reduce brain swelling
(select all that apply)
a. manitol
b. sodium thiopental
c. increase blood pressure
d. hyperventilation - Answer- a. manitol
b. sodium thiopental
d. hyperventilation
The median nerve in the normal population usually originates from nerve roots;
a. c3-c7
b. c5-t1
c. c4-c6
d. c5-c6 - Answer- b. c5-t1
ANASTAMOSIS? - Answer- -CONNECTION or opening BETWEEN two things
(especially cavities or passages) that are normally diverging or branching, such as
between blood vessels.
-COMMUNICATION BETWEEN ARTERIES
What causes the most airborne bacteria in OR?
a. blood on gown
b. blood spill
c. skin shed
d. patient vent - Answer- c. skin shed
Nerve that innervates 4th and 5th fingers? - Answer- Ulnar Nerve
Problem with Bilateral Synchronus Stim? - Answer- Can mask unilateral problems
No N20 at baseline could mean? - Answer- Stroke
What should you check 1st if you lose all waves? - Answer- Stimulator
Which of the following devices measures electrode resistance?
1. Ammeter
2. Ohmmeter
3. Voltmeter
4. Photometer - Answer- 2. Ohmmeter
,If an evoked potential has a voltage of 10uV and the associated noise has a voltage of
50uV, what is the signal to noise ratio after 100 averaged responses?
1. 1:1
2. 1:2
3. 2:1
4. 5:1 - Answer- 3. 2:1
To display median nerve SSEP response as an upward deflection, which of the
following must be known?
1. Waveform polarity and latency of the response
2. Waveform polarity and polarity convention of the amplifier inputs
3. Polarity convention of amplifier inputs and amplitude of the response
4. Latency of the response and polarity convention of the amplifier inputs - Answer- 2.
Waveform polarity and polarity convention of the amplifier inputs
If an amplifier is rated as having 120 dB common mode rejection rate, which of the
following ratios of in-phase to out-of-phase signals would be expected?
1. 10,000:1
2. 100,000:1
3. 500,000:1
4. 1,000,000:1 - Answer- 4. 1,000,000:1
Which of the following cranial nerves innervates the extraocular muscles?
1. Optic
2. Facial
3. Abducens
4. Trigeminal - Answer- 3. Abducens
Which of the following is an example of a SSEP far-field subcortical potential?
1. N20
2. N34
3. Erbs point
4. Popliteal Fossa - Answer- 2. N34
Which of the following opposes any change in current?
1. Capacitance
2. Impedance
3. Inductance
4. Resistance - Answer- 3. Inductance
, Which of the following electrode materials has little electrode potential drift and a long
time constant?
1. Tin
2. Gold
3. Silver
4. Stainless Steel - Answer- 2. Gold
Where should epidural electrodes be placed?
1. On the dura
2. In the spinal cord
3. Within the dural membrane
4. Between the dura and the spinal cord - Answer- 1. on the dura
With referential recording, maximal amplitude cortical evoked potentials following
stimulation of the left posterior tibial nerve usually would be found between?
1. C3 and CZ
2. C4 and P4
3. FZ and CZ
4. C4 and CZ - Answer- 1. C3 and CZ
For preoperative posterior tibial somatosensory evoked potentials, which of the
following would be the best ipsilateral location for the ground electrode?
1. Forearm
2. Calf
3. Shoulder
4. Palm - Answer- 2. Calf
To record the afferent volley after posterior tibial nerve stimulation, an electrode should
be placed on the?
1. Mastoid
2. Erbs point
3. T5 spine
4. Index Finger - Answer- 3. T5 spine
Impedances of applied electrodes should be?
1. balanced and below 5,000 ohms
2. balanced and above 5,000 ohms
3. unbalanced and below 5,000 ohms
4. unbalanced and above 5,000 ohms - Answer- 1. balanced and below 5,000 ohms
CORRECT ANSWERS 100% VERIFIED
2024/2025
Averaging a small amplitude signal, generated as response to a stimulus, that is buried
in noise will result in clarification of the signal of interest if which of these criteria are
met? (select all that apply)
a. the signal of interest (the response being measured) is the same for all repetitions of
the test (same amplitude, morphology and frequency)
b. the signal of interest is time locked to the stimulus, in other words, always at the
same time point relative to another event such as a stimulus
c. noise is different from, uncorrelated to and random compared to the signal of interest
- Answer- all of the above
Due to a smaller surface area, subdermal needle electrodes will have an impedance
that is:
a. improved by cleansing the skin with an abrasive gel before insertion
b. higher than surface electrodes, but usually equal and balanced when all subdermal
needle electrodes are used
c. lower than disk electrodes
d. unbalanced causing increased 60 Hz noise - Answer- b. higher than surface
electrodes, but usually equal and balanced when all subdermal need electrodes are
used
Glucose is monitored (and treated) during surgery because: (select all that apply)
a. glucose produces an intracellular acidosis during ischemia
b. low glucose levels are associated with worsened neurological injury
c. high glucose levels are associated with worsened neurological injury - Answer- all of
the above
In a medical legal case
a. having good supervision will get you off
b. a CNIM certification always protects the technologist from getting sued
c. none of the answers listed are correct
d. your lawyer will get you off
e. demonstrating knowledge of ASET literature will get you off - Answer- c. none of the
answers listed are correct
A stimulus pulse width that would tend to excite a larger population of motor fibers than
sensory fibers is:
a. 1 ms
,b. 0.05 ms
c. 0.5. ms
d. 0.2 ms - Answer- b. 0.05 ms
During a craniotomy for brain surgery which methods are used to reduce brain swelling
(select all that apply)
a. manitol
b. sodium thiopental
c. increase blood pressure
d. hyperventilation - Answer- a. manitol
b. sodium thiopental
d. hyperventilation
The median nerve in the normal population usually originates from nerve roots;
a. c3-c7
b. c5-t1
c. c4-c6
d. c5-c6 - Answer- b. c5-t1
ANASTAMOSIS? - Answer- -CONNECTION or opening BETWEEN two things
(especially cavities or passages) that are normally diverging or branching, such as
between blood vessels.
-COMMUNICATION BETWEEN ARTERIES
What causes the most airborne bacteria in OR?
a. blood on gown
b. blood spill
c. skin shed
d. patient vent - Answer- c. skin shed
Nerve that innervates 4th and 5th fingers? - Answer- Ulnar Nerve
Problem with Bilateral Synchronus Stim? - Answer- Can mask unilateral problems
No N20 at baseline could mean? - Answer- Stroke
What should you check 1st if you lose all waves? - Answer- Stimulator
Which of the following devices measures electrode resistance?
1. Ammeter
2. Ohmmeter
3. Voltmeter
4. Photometer - Answer- 2. Ohmmeter
,If an evoked potential has a voltage of 10uV and the associated noise has a voltage of
50uV, what is the signal to noise ratio after 100 averaged responses?
1. 1:1
2. 1:2
3. 2:1
4. 5:1 - Answer- 3. 2:1
To display median nerve SSEP response as an upward deflection, which of the
following must be known?
1. Waveform polarity and latency of the response
2. Waveform polarity and polarity convention of the amplifier inputs
3. Polarity convention of amplifier inputs and amplitude of the response
4. Latency of the response and polarity convention of the amplifier inputs - Answer- 2.
Waveform polarity and polarity convention of the amplifier inputs
If an amplifier is rated as having 120 dB common mode rejection rate, which of the
following ratios of in-phase to out-of-phase signals would be expected?
1. 10,000:1
2. 100,000:1
3. 500,000:1
4. 1,000,000:1 - Answer- 4. 1,000,000:1
Which of the following cranial nerves innervates the extraocular muscles?
1. Optic
2. Facial
3. Abducens
4. Trigeminal - Answer- 3. Abducens
Which of the following is an example of a SSEP far-field subcortical potential?
1. N20
2. N34
3. Erbs point
4. Popliteal Fossa - Answer- 2. N34
Which of the following opposes any change in current?
1. Capacitance
2. Impedance
3. Inductance
4. Resistance - Answer- 3. Inductance
, Which of the following electrode materials has little electrode potential drift and a long
time constant?
1. Tin
2. Gold
3. Silver
4. Stainless Steel - Answer- 2. Gold
Where should epidural electrodes be placed?
1. On the dura
2. In the spinal cord
3. Within the dural membrane
4. Between the dura and the spinal cord - Answer- 1. on the dura
With referential recording, maximal amplitude cortical evoked potentials following
stimulation of the left posterior tibial nerve usually would be found between?
1. C3 and CZ
2. C4 and P4
3. FZ and CZ
4. C4 and CZ - Answer- 1. C3 and CZ
For preoperative posterior tibial somatosensory evoked potentials, which of the
following would be the best ipsilateral location for the ground electrode?
1. Forearm
2. Calf
3. Shoulder
4. Palm - Answer- 2. Calf
To record the afferent volley after posterior tibial nerve stimulation, an electrode should
be placed on the?
1. Mastoid
2. Erbs point
3. T5 spine
4. Index Finger - Answer- 3. T5 spine
Impedances of applied electrodes should be?
1. balanced and below 5,000 ohms
2. balanced and above 5,000 ohms
3. unbalanced and below 5,000 ohms
4. unbalanced and above 5,000 ohms - Answer- 1. balanced and below 5,000 ohms
