Facial nerve EMG responses are best recorded from - ANSWER orbicularis oris and
orbicularis oculi muscles
What intravenous drug is used to maintain hypotension? - ANSWER Nutroprusside
At the stage of surgical anesthesia, propofol affects the BAEP by - ANSWER increasing
the latencies of waves I, III, and V without changing their amplitudes
If you have a signal to noise ratio of 1:2, averaging 64 responses will: - ANSWER improve
the ratio to 4:1
The central conduction time for MN SSEP is: - ANSWER P14 - N20
Spinal cord ischemia during aortic surgery is best detected by changes in the -
ANSWER posterior tibial nerve somatosensory evoked potential
At the end of an acoustic neuroma surgery you would test the facial nerve by
stimulating: - ANSWER Proximal to site of the tumor
In the operating room the stimulus intensity for activating a sensory nerve: - ANSWER
does not have established boundary
The effects of pharmacological or surgical manipulations can be mimicked by the
inappropriate manipulation of: - ANSWER filter settings
Elicit a motor twitch with PTN stimulation you would expect to see: - ANSWER Plantar
flexion of the toes
,What is the effect of fluid in the external auditory canal? - ANSWER Increase of absolute
latencies
Early changes to CMAPs during the exposure of CN VII are most likely due to - ANSWER
heating from the electrical cautery device
During microvascular decompression surgery to relieve a hemifacial spasm - ANSWER
a stimulation of CN VII elicits a response from the mentalis muscle
Of the following, the peak equivalent SPL of a click should be calibrated at: - ANSWER
1000 Hz
An unstable blood pressure during SSEP monitoring in the OR affects cortical EPs
resulting in - ANSWER fluctuating amplitudes
Multiple sclerosis, spinal cord injury, and brain trauma are some of the causes of
debilitating spasticity that has been relieved in some patients following: - ANSWER
selective dorsal rhizotomy
If a 10 microvolt signal inside 50 microvolts of noise is averaged for 100 traces, the final
signal to noise ratio will be: - ANSWER 2:1
A patient in a state of surgical anesthesia with nitrous oxide is likely to have a drop in
SSEP amplitudes of - ANSWER 0.75
Minimum bandpass filter for an evoked potential system? - ANSWER 0.1-5000 Hz
A patient is brought to the operating room with a diagnosis of a burst fracture of the first
lumbar vertebra. The most appropriate nerve(s) to monitor would be the: - ANSWER
posterior tibial and ulnar nerves
, If a sound intensity is decreased from 80 dB to 60 dB then the sound pressure has been
decreased by a factor of: - ANSWER 10
The "broadband click" refers to a - ANSWER peak acoustic power of 2 - 4 kHz
What is a rhizotomy? - ANSWER A procedure to selectively destroy problematic nerve
roots
If you are getting shocked from the system console, the first thing to do is: - ANSWER
Disconnect the patient
Which montage should be used optimally to assess the activity of the dorsal column? -
ANSWER Cs5-EPc
The earliest obligate component of the median nerve SSEP that is measured far-field is
generated in the: ANSWER Medial lemniscus
Preservation of facial nerve CMAPs - ANSWER does not always indicate a good surgical
outcome
The purpose of preoperative evoked potential testing is to: ANSWER Compare to
post-induction responses
Isolated amplifier inputs are for: - ANSWER prevent a flow of stray currents through
connecting lines to the patient
A secure method for applying surface cup electrodes requires: - ANSWER collodion and
compressed air
Nyquist Frequency - ANSWER Minimum sampling rate to prevent aliasing