CNIM FINAL EXAM AND PRACTICE
EXAM LATEST ACTUAL EXAM
QUESTRIONS AND CORRECT DETAILED
ANSWERS (VERIFIED ANSWERS)
|ALREADY GRADED A+
1. If an amplifier is rated as having 120dB common mode rejection ratio,
which of the following ratios of in-phase to out-of-phase signals would
be expected?
A) 100:1
B) 1,000:1
C) 10,000:1
D) 1,000,000:1
Correct ,,,,answer,,,: D
Rationale: CMRR in dB = 20 log (Vc/Vo). 120dB converts to
1,000,000:1 ratio. Higher CMRR means better rejection of common-
mode noise.
2. The vertical resolution of an evoked potential system depends
primarily on:
A) Sampling rate
B) Number of bits in the A/D converter
,C) Amplifier gain
D) Filter settings
Correct ,,,,answer,,,: B
Rationale: Vertical resolution is determined by the analog-to-digital
converter’s bit capacity (e.g., 8 bits = 256 amplitude steps). Higher bits
= finer resolution.
3. How frequently should EP machines be calibrated and safety tested?
A) Every 3 months
B) Every 6 months
C) Every 12 months
D) Every 24 months
Correct ,,,,answer,,,: B
Rationale: Regular calibration and safety testing every 6 months ensures
equipment accuracy and patient safety in the OR environment per
ABRET and facility guidelines.
4. A unit of resistance is symbolized by:
A) Volts
B) Amperes
C) Ohms
D) Siemens
,Correct ,,,,answer,,,: C
Rationale: Resistance is measured in ohms (Ω), representing opposition
to current flow in a circuit.
5. In a differential amp for intraoperative monitoring, common mode
rejection of in-phase signals is typically:
A) 100:1
B) 1,000:1
C) 10,000:1
D) 1,000,000:1
Correct ,,,,answer,,,: C
Rationale: Standard differential amplifiers reject common-mode signals
with a ratio of approximately 10,000:1, reducing noise from
environment.
6. An increase in stimulation intensity causes a linear increase of which
SSEP component?
A) N20
B) P37
C) P31
D) N50
Correct ,,,,answer,,,: C
Rationale: The P31 far-field potential demonstrates a linear increase in
amplitude with increasing stimulation intensity in SSEP.
, 7. The P31 response to posterior tibial nerve stimulation:
A) Is only seen in the lumbar spine
B) Is recordable over a generalized region of the scalp
C) Requires contralateral recording
D) Is a myogenic response
Correct ,,,,answer,,,: B
Rationale: P31 is a far-field potential generated from
brainstem/thalamus, recordable over broad scalp regions, not focal.
8. Lower extremity SSEPs are transmitted through the:
A) Cuneate nucleus
B) Gracilis nucleus
C) Ventral spinothalamic tract
D) Lateral corticospinal tract
Correct ,,,,answer,,,: B
Rationale: The gracile nucleus receives sensory input from lower
extremities via dorsal column pathway (proprioception/vibration).
9. The lumbar potential (LP) is generated from:
A) Dorsal root entry
B) Post-synaptic responses
C) Peripheral nerve
D) Brainstem
EXAM LATEST ACTUAL EXAM
QUESTRIONS AND CORRECT DETAILED
ANSWERS (VERIFIED ANSWERS)
|ALREADY GRADED A+
1. If an amplifier is rated as having 120dB common mode rejection ratio,
which of the following ratios of in-phase to out-of-phase signals would
be expected?
A) 100:1
B) 1,000:1
C) 10,000:1
D) 1,000,000:1
Correct ,,,,answer,,,: D
Rationale: CMRR in dB = 20 log (Vc/Vo). 120dB converts to
1,000,000:1 ratio. Higher CMRR means better rejection of common-
mode noise.
2. The vertical resolution of an evoked potential system depends
primarily on:
A) Sampling rate
B) Number of bits in the A/D converter
,C) Amplifier gain
D) Filter settings
Correct ,,,,answer,,,: B
Rationale: Vertical resolution is determined by the analog-to-digital
converter’s bit capacity (e.g., 8 bits = 256 amplitude steps). Higher bits
= finer resolution.
3. How frequently should EP machines be calibrated and safety tested?
A) Every 3 months
B) Every 6 months
C) Every 12 months
D) Every 24 months
Correct ,,,,answer,,,: B
Rationale: Regular calibration and safety testing every 6 months ensures
equipment accuracy and patient safety in the OR environment per
ABRET and facility guidelines.
4. A unit of resistance is symbolized by:
A) Volts
B) Amperes
C) Ohms
D) Siemens
,Correct ,,,,answer,,,: C
Rationale: Resistance is measured in ohms (Ω), representing opposition
to current flow in a circuit.
5. In a differential amp for intraoperative monitoring, common mode
rejection of in-phase signals is typically:
A) 100:1
B) 1,000:1
C) 10,000:1
D) 1,000,000:1
Correct ,,,,answer,,,: C
Rationale: Standard differential amplifiers reject common-mode signals
with a ratio of approximately 10,000:1, reducing noise from
environment.
6. An increase in stimulation intensity causes a linear increase of which
SSEP component?
A) N20
B) P37
C) P31
D) N50
Correct ,,,,answer,,,: C
Rationale: The P31 far-field potential demonstrates a linear increase in
amplitude with increasing stimulation intensity in SSEP.
, 7. The P31 response to posterior tibial nerve stimulation:
A) Is only seen in the lumbar spine
B) Is recordable over a generalized region of the scalp
C) Requires contralateral recording
D) Is a myogenic response
Correct ,,,,answer,,,: B
Rationale: P31 is a far-field potential generated from
brainstem/thalamus, recordable over broad scalp regions, not focal.
8. Lower extremity SSEPs are transmitted through the:
A) Cuneate nucleus
B) Gracilis nucleus
C) Ventral spinothalamic tract
D) Lateral corticospinal tract
Correct ,,,,answer,,,: B
Rationale: The gracile nucleus receives sensory input from lower
extremities via dorsal column pathway (proprioception/vibration).
9. The lumbar potential (LP) is generated from:
A) Dorsal root entry
B) Post-synaptic responses
C) Peripheral nerve
D) Brainstem
