The DS5 has been developed for the new and increasingly important field of Clinical Nerve Excitability Studies. These studies, including electrotonus and threshold electrotonus, are giving us added understanding of human nerve excitability and the pathophysiology of diseases such as diabetic neuropathy, carpal tunnel syndrome (CTS), amyotrophic lateral sclerosis (ALS), multifocal motor neuropathy (MMN), motor neurone disease (MND) taxolcisplatin neuropathy and neuromyotonia.

Multiple Applications

Although the DS5 has been primarily designed for clinical studies of peripheral nerves using threshold tracking techniques, because the unit provides a current output proportional to the voltage input and can deliver up to ±50mA (from a compliance voltage of greater than ±100V), it should appeal to any researchers wishing to safely apply a computer controlled constant current stimulus to a patient or research volunteer.

Unlimited Stimulus Profile Possibilities

Unlike other clinical stimulators, the DS5 is not a traditional “square wave pulse stimulator”. Instead, the DS5 will produce an isolated constant current stimulus proportional to a voltage applied at its input, with the shape of the input waveform describing the shape of the stimulus. As a result, when driven by a computer running appropriate software, the DS5 is capable of generating a stimulus consisting of multiple components including sine waves, ramps, square waves or totally arbitrary waveforms. Patient safety is assured at all times by the implementation of safety features which, amongst other things, also limit the amount of energy passed to the subject.

Stimulus Control via Commercial or Specialist Hardware / Software

The DS5 has been developed in collaboration with Professor Hugh Bostock at the Institute of Neurology in London, who uses the stimulator to facilitate the threshold tracking measurements alluded to above. Briefly, muscle action potentials evoked by a test stimulus from the DS5 are amplified and compared with a desired “target response”. The resultant “error signal” is used to modulate the amplitude of the test stimulus. Once a baseline level of excitability is established, conditioning pulses can be applied to examine their effect on the excitability of the nerve being studied. By carrying out this procedure using his own specialist software, diagnostic tests can be partially automated and completed more rapidly.