CNIM Somatosensory Evoked Potentials (SSEP) 3

Question 1

Interpeak latency between N20 and N13 reflects conduction through which segment of the somatosensory pathway?

Accepted Answer

Cervical spinal cord to cortex

Answer

Peripheral nerve to spinal cord

Answer

Thalamus to cortex

Answer

Cortex to cortex

Question 2

Which stimulation parameter is most important for obtaining optimal SSEP responses during intraoperative monitoring?

Accepted Answer

Pulse duration and current intensity sufficient to produce a motor twitch

Answer

Frequency of stimulation

Answer

Phase of stimulation

Answer

Electrode impedance above 20 kΩ

Question 3

A unilateral loss of SSEP with the contralateral side intact during cervical spine surgery most likely suggests:

Accepted Answer

Ipsilateral posterior spinal cord or nerve root compromise

Answer

Global hypotension

Answer

Equipment malfunction affecting one channel

Answer

Anesthetic effect

Question 4

What is the typical stimulation pulse duration used for median nerve SSEP in intraoperative monitoring?

Accepted Answer

0.2 ms

Answer

0.01 ms

Answer

5 ms

Answer

20 ms

Question 5

Why are reference baselines obtained after anesthetic induction but before surgical incision in SSEP monitoring?

Accepted Answer

To establish anesthetic-state baselines that account for drug effects before comparing surgical changes

Answer

To test electrode integrity only

Answer

To satisfy regulatory documentation requirements

Answer

To calibrate the amplifier gain

Question 6

Which condition is SSEP monitoring LEAST sensitive for detecting during spinal cord surgery?

Accepted Answer

Anterior cord syndrome

Answer

Posterior column injury

Answer

Nerve root compression

Answer

Brachial plexus traction