In a transcutaneous electric nerve stimulator for producing in a predetermined sequence of different types of waveforms (in which the frequency varies, the signal is successively and/or intermittently created, etc.), when the user depresses a predetermined switch while a desired waveform is being outputted, a low-frequency signal of the waveform is thereafter continuously produced. In a transcutaneous electric nerve stimulator capable of selectively producing low-frequency signals of at least tw...

The present invention pertains to a portable non-invasive electronic apparatus which can be used to relieve pain or alter the symptoms of certain neurological dysfunctions. A specifically contoured constant current and current limited waveform is generated and applied to selectively positioned electrodes. A program controlled processor tracks usage of the unit to prevent abuse and monitor progress. An overall treatment regimen centered on the stimulator may be effected simply and safely.

Heart stimulation apparatus, which is constructed as an implantable unit including a heart stimulator, terminal electrodes of the heart stimulator connectable to a patient's heart and a number of different shunts connected in parallel across the terminal electrodes each shunt having a separate remotely operable isolating switch, operable magnetically and a Zener diode, the known trigger voltage of each Zener diode being different. In use the shunts are remotely switched magnetically from the ext...

This invention relates to an instrument for disintegrating calculi in the urinary tract by hydraulic impacts formed by electrical discharges in the liquid medium surrounding the calculi. Instruments employing this general principle are well known and they usually consist of a lithotrite having two electrodes, and a pulse forming network connected to the electrodes to provide electrical energy for forming discharge between the lithotrite electrodes. In the lines connecting the pulse forming netwo...

A method and apparatus are provided for electrically stimulating muscle of individuals having little or no nerve damage so the muscle can be power contracted with little pain to the individual. A therapeutic current is applied to the muscle which includes alternating desensitizing and stimulus currents. The desensitizing current is a high frequency, low amplitude current to desensitize the muscle and the stimulus current is a low frequency, high amplitude current to stimulate the muscle. The cur...

An electric circuit arrangement for an electric muscle stimulator comprising a surging waveform generator, a pulse generator of higher frequency than the surging waveform generator, and a gating circuit connected to the surging waveform generator and the pulse generator and from which bursts of unidirectional pulses are obtained, the repetition frequency of the bursts being that of the surging waveform generator. A transformer has at least one primary winding and at least one secondary winding, ...

A method and apparatus for eliciting a physiologically significant cough reflex, such as in a quadriplegic patient. The apparatus preferably at least one pair of electrodes which are positioned about or near the abdominal muscles. A pushbutton switch is preferably used to generate an input signal. An oscillator is preferably used to generate a stimulus pulse signal. The input signal and the stimulus pulse signal are computed into an output signal. The output signal is transformed into a pulse el...

An apparatus for transcutaneous electric nerve stimulation (TNS) with a power supply, a frequency generator and an electric circuit for the generation of different output frequencies of variable intensity at the output electrodes which may be connected to the apparatus and to an output short circuit to improve the pulse form emitted. The output short circuit network comprises a transistor T1, which upon actuation by a triggering pulse activates with its collector the base of a subsequent transis...

A dual channel neuromuscular stimulator. Pulses developed by a pulse generator are transmitted alternately on both channels to involuntarily contract muscles. The stimulator has variable on/off cycling capability to provide flexibility in meeting the stimulation needs of patients and has output current adjustments and other variable parameter settings to achieve optimum neuromuscular stimulation. To enhance patient comfort, the stimulation output of the stimulator can be slowly "ramped up" to it...

An implant for stimulating the vagus nerve receives commands over a radio frequency link. The implant disables a voltage convertor used in providing the stimulation signal at periodic intervals to monitor for communications attempts. The implant provides radio frequency marker pulses before providing stimulation signals of certain frequencies. During the providing of stimulation signals the implant monitors the voltage overhead present between the voltage source and the load and adjusts the over...