EDT Device Setup & Operation 2

Question 1

When performing a median nerve motor study, which filter settings are most appropriate for recording the CMAP?

Accepted Answer

High-pass 2 Hz, low-pass 10 kHz

Answer

Motor NCS uses a bandpass of 2–10,000 Hz to capture the full frequency range of compound muscle action potentials.

Question 2

A technician notices 60 Hz artifact on the EMG display. Which step should be taken FIRST?

Accepted Answer

Check and improve electrode impedance and ground connections

Answer

Poor electrode contact and inadequate grounding are the most common causes of 60 Hz artifact, and correcting these is preferred before using the notch filter.

Question 3

For an F-wave study, how should sweep speed typically be adjusted compared to a standard distal motor latency recording?

Accepted Answer

Increased to 100 ms/div or more

Answer

F-waves travel to the spinal cord and back, requiring a longer time window (100 ms or more) to capture the late response.

Question 4

Which electrode configuration is used for the active (E1) recording electrode in a standard nerve conduction study?

Accepted Answer

Placed over the motor point or muscle belly

Answer

E1 is placed over the motor point (belly) of the target muscle to maximize CMAP amplitude.

Question 5

During repetitive nerve stimulation, at what frequency is slow repetitive stimulation typically performed to assess neuromuscular junction disorders?

Accepted Answer

1–3 Hz

Answer

Slow repetitive stimulation at 2–3 Hz reveals decremental responses characteristic of postsynaptic NMJ disorders such as myasthenia gravis.

(EDT) Electrodiagnostic Technician Certification Practice Test

(EDT) Electrodiagnostic Technician Certification Practice Test

EDT Device Setup & Operation 2