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Motor NCS electrode placement
•
The active recording electrode is placed over the endplate zone of a muscle innervated by the tested nerve.
•
The reference electrode is placed nearby in an electrically “quiet” area.
•
The ground electrode is usually placed between the stimulating and recording electrodes.
•
Using electrolytic gel between the skin and recording electrode improves the “electrical contact” and reduces noise.
•
Excessive noise may require abrading the skin to lower impedances.
•
The nerve is stimulated using surface electrodes at two or more sites where the nerve is located superficially. The stimulator is
commonly oriented so that the cathode of the stimulator faces the active recording electrode.
Sensory NCS electrode placement
1.
Surface disk or ring electrodes are placed over the skin where the tested nerve is located superficially.
2.
The nerve is stimulated at sites where it is located superficially.
The cathode of the stimulator is oriented towards the active recording electrode.
Acquire the data
Data is acquired by the instrument, displayed on-screen, and marked and saved automatically. The waveforms and
the measured values are then transferred to a Report.
1.
Set the stimulus intensity to
0
.
2.
Position the stimulator at the appropriate site.
3.
Press the
Single Stimulus
key on the control panel (or footswitch or the
Acquire
button above the wheel on the
stimulator probe) to stimulate and acquire responses.
4.
Use the
Stimulus Intensity
control knob or the Intensity wheel on the stimulator probe to gradually increase the
intensity of the electrical stimulus until the response is maximal.
5.
If using continuous stimulation, press the
Repetitive
key on the Control Panel or press and hold briefly the
Acquire
button on the stimulator probe. When an acceptable response is observed, press either button again to stop
stimulation.
6.
To average, press the
Average
function key on the Control Panel. The averager is then enabled. Press the
Repetitive
key on the Control Panel to acquire the defined number of sweeps.
7.
To advance to the next stimulus site, press the
Next Site
down arrow from the Navigation keys or the A button on the
probe.
8.
Follow the same procedure to obtain a response for each required site.
Marking data
1.
Markers are placed automatically as the responses are acquired.
2.
To adjust the markers, click the desired marker and drag it to its new location or use the Cursor Knob to move
the Red marker; push the Cursor Knob to advance to the next marker.
3.
Press the Cursor Knob to activate/advance through the markers. Turn the knob to position the active marker
(Red).
