natus XLTEK Protektor32, Инструкция по эксплуатации

Страница: 33 / 81

XLTEK Protektor32 Instructions for Use
31
Current Density
When using TcMEP mode you must be aware of the Current density . Current density is dependent on
the stimulation strength (voltage) and number of pulses. In order to achieve current densities less than 2
mA rms / cm 2 you can use the parameter settings-setup appearing in Table 4.
Table 4: Maximum voltage - number of pulses combinations to achieve less than 2 mA rms/cm 2 .
Maximum voltage settings per pulse setting per electrode configuration to avoid current densities above
2mA
RMS
/cm 2
Pulses per second 1 2 3 4 5 6 7 8 9
One EEG disc electrode (0.9cm 2 )
Voltage Settings [V] 255 180 147 127 114 104 96 90 85
DISPOSABLE SILVER EEG DISC ELECTRODES - Diameter of cup: 10 mm; Height of cup: 3 mm;
Surface area = 90 mm 2 (Part #105191 in the Natus Neurodiagnostic Accessories Catalogue)
If you use settings-setups combinations exciding those detailed in Table 4 above, stimulation
may result in skin burns and will require special attention of the operator.
t = Pulse Duration – Fixed at 50us
i = Interpulse Interval (pulse rate)
Note: Num Priming Num Test Pulses cannot exceed 9 total.
1
2
num priming
pulses
... ...
num test
pulses
1 2
t
i
Priming Gap
Priming Pulses Test Pulses
i