[Development, optimization and evaluation of new instruments for magnetomotor stimulation of nerve fibers]

Over the past few years, magnetomotive nerve stimulation--an almost painless procedure--has become increasingly important for both diagnosis and therapy. However, the actual efficiency of this method is highly dependent on the technology available. For this reason, current research programmes are focussed on the development of new devices. Individual components can be optimized only with respect to a particular application. As a means of stimulating deeper-lying nerve fibres, a powerful air coil was developed. A second, optimally focussed, air coil permits the selective stimulation of closely defined areas. For the operation of the two coils, a power source has been specially designed to provide particularly high-energy pulses, as well as an option for repetitive stimulation. This unit was designed to comply with relevant regulations, and incorporates effective safety functions, some employing redundancy backup. Within the performance limits of the device, the configuration of the stimulation pulses is to a large extent freely programmable. In addition to standard applications, this power supply unit opens up new fields of application for magnetomotive stimulation. The first series of tests carried out with this new stimulation system confirmed--among other things--the achievement of the desired depth effect of the air coil. By virtue of its highly focussed effect, the second coil has proved to be particularly suitable for stimulating the motor cortex.