Cnim Abret Questions And Answers

Scalp position of electrodes most critical? - Answer- Lower extremity SSEP evoked potential has a voltage of 10 uV and the associated noise has a voltage of 50 uV, what is the signal-to-noise ratio after 100 averaged responses? - Answer- 2:1 To display median nerve SSEP response as an upward deflection, which of the following must be known? - Answer- Waveform polarity and polarity convention of the amplifier inputs If an amplifier is rated at having 120dB common mode rejection ratio, which of the following ratios of in-phase to out-of-phase signals would be expected? - Answer- 1,000,000:1 Which of the following cranial nerves innervates the extraocular muscles? - Answer- Abducens Which of the following is an example of an SSEP far-field subcortical potential? - Answer- N34 What is the segmental motor innervation of the peroneus longus - Answer- L4, L5, and S1 Which of the following opposes any change in current? - Answer- Inductance The dorsal column pathways synapse at which loci on their way to the sensory cortex? - Answer- Nucleus cuneatus and thalamus With referential recording, maximal amplitude cortical evoked potentials following stimulation of the left posterior tibial nerve usually would be found between: - Answer- C3 and Cz For preoperative posterior tibial SSEPs, which of the following would be the best ipsilateral location for the ground electrode? - Answer- Calf To record the afferent volley after posterior tibial nerve stimulation, an electrode should be placed on the: - Answer- T5 spine