ASET Certification in Neurophysiologic Intraoperative Monitoring (CNIM) Practice Exam

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• What is the impact of external interference on evoked potentials?
• During scoliosis surgery, SSEP monitoring may replace the need for which test?
• During which type of surgery are SSEPs primarily utilized?
• Why are dural or direct cord recordings advantageous when monitoring SSEPs?
• What is the suggested rate of stimulation for intraoperative posterior tibial nerve evoked potential monitoring?
• How does reducing the high-frequency filter affect evoked potential latency?
• From which nerve roots does the ulnar nerve originate?
• What should be the priority for a neurophysiologic monitoring professional during a surgical procedure?
• What is the maximum leakage current through patient leads to protect against shock during power-on and power-off?
• Universal precautions are designed to eliminate potential contact with body fluids that transmit what?
• What can help decrease stimulus artifact during SSEPs?
• What is the guidance for setting the stimulation intensity for activating a sensory nerve in the operating room?
• What is the goal of performing intraoperative neurophysiological monitoring (IONM)?
• Which response in the upper extremity somatosensory evoked potential (UE SSEP) is classified as a "stationary potential"?
• What is the primary function of the high-frequency filter in SSEP monitoring?
• Which instrumentation system is used to restore normal vertebral column alignment?
• Where does the vestibulocochlear nerve (CN VIII) appear?
• What does the BAER measurement of the III-V interpeak interval represent?
• Which pulse width would stimulate a larger population of motor fibers compared to sensory fibers?
• What could be a reason for a "false-negative" outcome during monitoring?
• Which electrode is recommended as a sensitive stimulator during facial nerve recordings?
• What is the ideal outcome when improving the signal-to-noise ratio through averaging?
• An advantage to using grid or strip electrodes over the "crown of thorns" for recording the ECoG is their ability to:
• What role do retraction devices play during neurophysiologic monitoring?
• What is the minimum input impedance required for a differential amplifier?
• What is a likely effect of a drop in temperature of the patient's legs during monitoring?
• Which section of the brainstem connects continuously with the spinal cord and includes the decussation of the pyramids?
• What type of recordings can be made using electrodes embedded in a thin sheet of plastic material?
• In SSEPs, what is a common source of interference that practitioners must monitor?
• Which type of electrode would typically exhibit lower impedance when properly placed?
• When using a C5 spine to Fpz montage with lower extremity stimulation, the expected response is generated at which location?
• What does a "false-negative" test indicate?
• To stimulate both tibial nerves asynchronously, what must be done?
• How does propofol affect the BAER at the stage of surgical anesthesia?
• Which anesthetic agent has the least effect on SSEP waveforms?
• Which of the following materials is considered a good insulating material that inhibits current flow?
• During a posterior fossa approach for acoustic neuroma removal, what most likely causes an increase in the latency of wave V?
• Which of the following is a common source of non-physiologic artifact in the OR?
• To reduce artifact from electrode wire movement during surgery, what is the best method?
• How will the amplifier display move in response to the difference between the voltages in input 1 and input 2?
• What term describes very low currents that may be lethal to patients with indwelling electrodes or catheters?
• What type of electrophysiologic changes can IONM detect during surgical procedures?
• What is the principal effect of etomidate on EPs during surgical anesthesia?
• What procedure has shown to relieve spasticity in some patients with MS, spinal cord injury, and brain trauma?
• The median nerve SSEP can provide helpful information regarding which aspect?
• Synaptic transmission is believed to produce which of the following potentials?
• During monitoring, what is critical to maintain the integrity of the recording?
• What is the best application for Luque rods?
• The posterior tibial nerve arises from which branch of the sciatic nerve?
• When monitoring median nerve SSEPs during posterior fossa exploration for tic douloureaux, what will it show?
• What is the purpose of placing electrodes during intraoperative monitoring of BAERs?
• For a patient with a herniated C5/6 disc, which nerves are most appropriate to monitor during surgery?
• Why is the correct placement of electrodes crucial in facial nerve monitoring?
• What is the expected cortical response time when stimulating the median nerve at the wrist in a normal adult?
• EP waveforms contralateral to the surgical site are monitored to differentiate between what factors?
• To record cortical SSEPs during intraoperative monitoring of cervical spinal cord surgery, where should electrodes be placed?
• The sound stimulus intensity at the tympanic membrane is influenced by which of the following?
• What are the effects of halogenated agents on the cortical SSEP?
• Which factor is critical when evaluating the timing of responses in evoked potentials?
• Which recommendation can minimize stimulus artifact while recording the BAER in the operating room?
• What is the effect of sublaminar wires during surgical procedures?
• When dealing with potential artifacts in waveforms, which approach is least effective?
• Sublaminar wires are typically used to apply which type of corrective force to the spinal column?
• Why is well-maintained documentation imperative throughout a surgical case?
• In SSEP monitoring, the amplitude of waveforms can be influenced by what?
• Which abnormality may be associated with vascular malformations of the posterior fossa alongside hemifacial spasm and facial paresis?
• An EP recording system should allow averaging of how many trials at a minimum?
• In a bipolar montage during EEG recording, what indicates a localizing sign?
• What is the sensitivity setting on an amplifier that produces a vertical deflection of 1 cm with an input of 10mV?
• When using constant voltage for facial nerve stimulation and the nerve is bathed in CSF, what occurs after the area is suctioned?
• The basis for artifact rejection is the assumption that responses of excessive amplitude likely contain what?
• What does the Fpz-C5s channel record when performing a posterior tibial nerve SSEP?
• P14 is a far-field response likely reflecting which of the following?
• What will direct focal electrical stimulation of a peripheral nerve lesion achieve?
• If you have a signal to noise ratio of 1:2, what will be the effect of averaging 64 responses?
• Which method is considered secure for applying surface cup electrodes?
• What is the recommended horizontal resolution for an evoked potential system?
• Intracranial cortical stimulation and recording can be utilized to achieve which of the following?
• What is a potential result of decreasing body temperature in a surgical patient monitored with EPs?
• Where should the electrode be placed to record the cervical cord response to median nerve stimulation?
• What type of change might monitoring somatosensory function fail to recognize?
• Which of the following best describes spectral edge?
• For monitoring, stimulation of the spinal cord to elicit MEPs is most useful for which function?
• How is "Hearing level" (HL) defined?
• What must be avoided when monitoring the facial nerve?
• In the selection of horizontal parameters for analysis, what should the sampling rate be?
• When can a nerve cell membrane depolarize?
• During MVD surgery to relieve a hemifacial spasm, which CN stimulation elicits a response from the mentalis muscle?
• Which of the following structures lies between adjacent vertebral bodies and connects them?
• What is the minimum common mode rejection ratio for amplifiers used in evoked potential recording?
• Why is it important to begin monitoring EEG early during a carotid endarterectomy?
• What is the effect of severe hypothermia on EP latencies?
• Maximum variability of cortical EP potentials will most likely occur?
• Spinal cord ischemia during aortic surgery is best detected by changes in which potential?
• What does a decreased nerve conduction velocity between the pop fossa and L3 potential indicate during tibial nerve stimulation?
• When used as an induction agent, which of the following drugs will have the least effect on the SSEP?
• What factor significantly affects the quality of the evoked potential data collected during monitoring?
• Which connective tissue membrane covers the brain's innermost layer?
• A patient under surgical anesthesia using N2O is likely to experience what change in SSEP amplitudes?
• The common peroneal nerve arises from which nerve?
• What is the primary function of capacitors in electronic devices?
• Which of the following is true regarding the use of etomidate on EPs?
• What is the consequence of changing the setting of the high-frequency filter during SSEP monitoring?
• What does a differential amplifier record?
• Cortical evoked potentials are largely produced by which of the following mechanisms?
• To optimally monitor CN VIII function in the OR, what should be performed simultaneously?
• What is the primary function of surface cup electrodes in neurophysiologic monitoring?
• During which phase of scoliosis surgery is the spinal cord most at risk for injury?
• To record the compound action potential of the median nerve intraoperatively, where should the electrode be placed?
• Which of the following is a key advantage of direct cord recordings when monitoring during procedures?
• Which neurotransmitter can inhibit the postsynaptic neuron?
• What is a goal of intraoperative neurophysiologic monitoring (IONM) of the sensory pathways?
• In what way can EMG artifacts be minimized when performing SSEPs?
• Why should raw EEG be available for review during quantitative EEG monitoring?
• Electrode impedance is defined as the opposition to which type of current flow?
• What change in the BAER would be expected when cerebral blood supply to the brainstem is significantly reduced?
• A major disadvantage of monitoring only posterior tibial nerve SSEP during scoliosis surgery is the inability to?
• What forms the peripheral nerves such as the ulnar and femoral nerves?
• Which structure generates Wave III of the Brainstem Auditory Evoked Response (BAER)?
• In patients showing clamp-related EEG changes during CEA, when do 80% of changes typically appear?
• Which surgical procedure carries the greatest risk for changes in cardiovascular and respiratory efforts?
• Which factor is least likely to create EMG artifact interference during nerve monitoring?
• What is the most likely reason for early changes to CMAPs during exposure of CN VII?
• What characteristic of subdermal needle electrodes results in higher impedance compared to surface electrodes?
• The signal-to-noise ratio pertains to the relationship between what two elements?
• How does severe hypotension affect the EP?
• What is the primary use of functional cortical stimulation during surgery?
• What does the phenomenon called aliasing refer to?
• What criteria should prompt a surgeon notification when monitoring BAERs during surgery?
• What effect does filtering have on the detail observed in an evoked potential waveform?
• Which factor can result in fluctuating amplitudes during monitoring?
• For median nerve stimulation, where is the cathode placed?
• Subdermal needle electrodes must be inserted symmetrically over homologous brain areas to avoid:
• What is the purpose of isolated amplifier inputs in neurophysiologic monitoring?
• The peroneal and tibial nerves are divisions of which nerve?
• Why is the use of the 60Hz notch filter discouraged during recording?
• What is the suggested masking level to eliminate crossover responses?
• Which of the following parameters is related to the performance of a differential amplifier?
• How does the amplitude of a cortical response change with increased stimulation rates?
• What can pharmacological or surgical manipulations be mimicked by?
• During Carotid Endarterectomy (CEA), which monitoring procedure is essential?
• What does spectral analysis of raw EEG data display as an upward deflection?
• For a patient with a burst fracture of the first lumbar vertebra, which nerves are most appropriate to monitor?
• In MEP studies, where should the anode be placed in relation to the cathode?
• What technique can help avoid crossover sound stimulation during BAER testing?
• Most evoked potentials (EPs) are considered to be what type of response?
• With exposure provided by laminectomy, where can needle electrodes record spinal activity?
• Brain activity recorded directly from the cortex (ECoG) typically requires sensitivities in which range?
• What is a key responsibility of the EP monitoring team?
• During the procedure of SSEPs, which method is effective in reducing EMG artifact?
• One effect of ketamine on the SSEP is to?
• What type of testing is most commonly utilized in the assessment of intraoperative monitoring?
• What does a constant voltage stimulator do?
• What is the recommended electrode placement for recording cortical SSEPs during intraoperative monitoring of the thoracolumbar spinal cord?
• For which condition is it most appropriate to monitor the median nerve?
• Which characteristic is most important for an evoked potential system's sampling rate?
• What is a contraindication for using transcranial magnetic stimulation?
• Where are the recording electrodes placed to monitor cranial nerve X?
• What is the single most important step taken to avoid contamination?
• What is the resting membrane potential of a typical neuron?
• Why should IONM continue despite electrical cautery obliterating EP waveforms?
• Given a circuit with a resistance of 1000 ohms and a voltage of 10 volts, what is the resultant current flow?
• What stimulation rate causes at least 80% attenuation of the cortical response to posterior tibial SSEP stimulation?
• All of the following are true of magnetic stimulation except:
• At a sampling rate of 10 kHz, what is the shortest sine wave that can be resolved?
• The median nerve originates from which nerve roots?
• A rarefaction click occurs when the initial movement of a transducer diaphragm is:
• What ion concentrations primarily create resting membrane potential?
• What is typically monitored to assess spinal cord function during surgeries?
• What effect does an increase in inhalation agents typically have on CMAPs during surgery?
• What artifact type can compromise data integrity during monitoring?
• On the SSEP, which electrode position records a spinal cord response?
• What is required for effective communication by the monitoring tech?
• Why is it important to monitor waveforms contralateral to the surgical site?
• What is an advantage of using a bipolar type stimulator over a monopolar stimulator for cranial nerve VII stimulation?
• What serves as a lever for muscle and ligaments projected laterally from the junction of the pedicle and lamina?
• What does prestimulus triggering include in its process?
• A ground loop occurs when...
• In the operating room, what potential issue can arise from using several inches of tubing to connect the transducer and ear inserts during BAER testing?
• An "after-discharge" can occur on the cortical EEG recording after what event?
• What type of artifact is most likely associated with blood warming equipment?
• What problem may arise from using compressible tubing during intraoperative BAERs?
• How is the median nerve SSEP-N18 potential typically recorded?
• Which of the following is most likely to cause airborne contamination in an operating room?
• Which condition is likely to make SSEPs highly variable and less reliable?
• What is the primary purpose of averaging in an EP recording system?
• To minimize pain during the recording of SSEPs, the contact impedance of the stimulator should be:
• What is the maximum voltage that should be measured across an impedance of 1000 ohms according to standard grounding procedures?
• Which method does the ISOLA type of spinal instrumentation typically use?
• What is an advantage of referential recording compared to bipolar recording for SSEPs?
• What symptoms would a patient likely present with prior to surgery for the removal of an acoustic neuroma?
• Which neurotransmitter is responsible for the excitation of the postsynaptic neuron?
• The facial nerve is cranial nerve ____ and it supplies muscle for _____.
• Which monitoring modality is most likely to be affected by a large bolus of muscle relaxant?
• Which type of instrumentation is most likely to cause trauma to the spinal cord?
• What is the gain of an amplifier set to yield an output signal of 1 volt for an input signal of 10µV?
• What does the term "broadband click" refer to in acoustic power?
• When stimulating the posterior tibial nerve at the ankle, how can stimulation be confirmed?
• What is the recommended impedance range for a scalp electrode during intraoperative EEG recording?
• Which method can achieve stimulation of the motor pathway with minimal movement in the surgical field?
• Which item should not be included in the techs data sheet during OR EP monitoring?
• In a patient with a hematocrit below 10%, how does the SSEP waveform typically change?
• Which of the following is an example of a non-physiologic artifact?
• What should the impedance levels be monitored for during a surgical procedure?
• To ensure proper functioning of the monitoring equipment, which aspect must be regularly checked?
• In neurophysiologic monitoring, what is the function of a grounding device?
• When performing MEP studies, what is the positioning of the anode in relation to the cathode important for?
• How does unstable blood pressure during SSEP monitoring in the OR affect cortical EPs?
• What do spinal nerves emerge through?
• What is true about the initial waveform recorded of a near-field potential?
• When monitoring SSEP waveforms, which change can help improve signal quality?
• Which of the following can affect both SSEP and BAER waveforms?
• What bench test is important for ensuring the functional reliability of monitoring equipment?
• What is the effect of volatile anesthetic agents on cortical EPs?
• An inhibitory transmitter affects the resting membrane potential of the post-synaptic neuron by causing it to:
• Why should electrodes be sealed with tape when recording intraoperative BAERs?
• What does the preservation of facial nerve CMAPs indicate?
• What must be matched to accurately represent the amplitude of an EP waveform?
• Why are preoperative baselines and SSEP values essential in Intraoperative Neurophysiologic Monitoring (IONM)?
• The effects of Harrington rod distraction on the spinal cord can be tested by all of the following except:
• What is a benefit of using a 10 kHz sampling rate in neuromonitoring?
• Facial nerve EMG responses are best recorded from which muscles?
• During intraoperative neuromonitoring, what does no change in the peripheral responses indicate with significant changes in cervical and cortical SSEPs?
• What is the primary function of a condensation click?