| Amplitude:
The magnitude or intensity of
the current. Measured in peak mA. |
| Phase
Duration: The time elapsed from
the beginning to the termination of one
phase of a pulse. Measured in
microseconds (µsec.) |
| Pulse
Duration: (Pulse Width) The time
elapsed from the beginning to the end of
all phases plus the interphase interval
within one pulse. Measured in
microseconds (µsec.) |
| Interphase
Interval: (Intrapulse Interval) The
time between two successive components of
pulse when no electrical activity occurs.
Measured in microseconds (µsec.) |
| Interpulse
Interval: The time between two
successive pulses. |
Pulse
Rate: The number of pulses per
measure of time (one second). Also
referred to as frequency. Measured in
hertz (Hz).
|
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| Symmetrical
Biphasic |
Asymmetrical
Biphasic |
|
Most TENS units utilize an asymmetrical
biphasic waveform. With biphasic
waveforms there is not the problem of
producing a net skin charge which
could lead to possible burns.
Asymmetrical biphasic waveforms have two
phases, an active phase and a balancing
(usually passive) phase. In the active
phase the positive going current travels
through the positive electrode into the
tissue, and during the balancing phase
the current returns out the negative
electrode. A mirror image of the waveform
at the positive electrode occurs at the
negative electrode.
Neurons depolarize more readily to
negative current.
|
NERVE
CELLS ARE POLARIZED; INSIDE IS NEGATIVE
AND OUTSIDE IS POSITIVE
|
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