High frequency high intensity transcutaneous electrical nerve stimulator and method of treatment

• US 5,052,391 A
• Filed: 10/22/1990
• Issued: 10/01/1991
• Est. Priority Date: 10/22/1990
• Status: Expired due to Term

• Current Assignee: RFP, Inc.
• Original Assignee: RFP, Inc.
• Inventors: Silberstone, Leon M., Halleck, Michael E.
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US07/601,150
• Time in Patent Office: 344 Days
• Field of Search: 128/419 R, 128/421, 128/422, 600/27, 606/32, 606/40, 606/52
• US Class Current: 607/46
• CPC Class Codes: A61N 1/06 for high-frequency therapy
• CPC Class Codes: A61N 1/36021 for treatment of pain

Abstract

A transcutaneous electrical nerve stimulation (TENS) device provides significantly improved patient results by supplying high frequency electrical pulses at frequencies in a range of 2.5 to 60 kilohertz. The frequency and intensity of the pulses can be adjusted, to treat the patient at the optimal frequency and amplitude in order to treat chronic or acute pain or to block the pain caused by a traumatic or medical procedure. Starting at a mid-level of intensity where no stimulation occurs, the frequency is adjusted downwardly until there is some nerse sensation. At this point, the procedure may be performed while the frequency is adjusted downwardly as needed to maintain nerve sansation. The wave form characteristic of the pulses is an AC wave form with a square wave portion with rapid rise time and slower fall time followed by a pulse portion of the opposite polarity compared to the square wave portion.

Claims

1. A method for blocking the pain caused by a traumatic or medical procedure on a patient with the use of transcutaneous electrical nerve stimulation, comprising the steps of:

(a) generating a series of electrical pulses at a frequency in the range of 2.5 to 60 kilohertz;

(b) applying said generated electrical pulses to a desired area on a patient'"'"'s body;

(c) electrically conducting the applied electrical pulses through the patient'"'"'s body to stimulate selected nerves; and

(d) performing the procedure.

2. A method as defined in claim 1 wherein generating the series of electrical pulses includes:

generating the electrical pulses with an electrically powered stimulator; and

electrically isolating the patient from the stimulator.

3. A method as defined in claim 2 wherein electrically isolating the patient from the stimulator comprises coupling a signal generated by the stimulator through a transformer to the patient.

4. A method as defined in claim 1 wherein the generating step further comprises adjusting the frequency of the electrical pulses within said range.

5. A method as defined in claim 4 further comprising adjusting the high frequency electrical pulses to 60 kilohertz.

6. A method as defined in claim 4 wherein generating the series of electrical impulses further comprises adjusting the intensity of the electrical pulses.

7. A method as defined in claim 6, further comprising the additional steps of:

(e) adjusting the frequency to the highest frequency within the frequency adjustment range;

(f) adjusting the intensity to the lowest intensity within the intensity adjustment range;

then

(g) adjusting the intensity to a level which is slightly below that level which achieves perceptible nerve sensation to the patient;

(h) adjusting the frequency downward from the highest frequency to a relatively lower frequency until the patient begins to perceive a nerve sensation; and

(i) continuing to adjust the frequency downwardly as necessary throughout the procedure to maintain the nerve sensation.

8. A method as defined in claim 1 further including forming the high frequency electrical pulses to include a square wave portion and an opposite polarity pulse centered about a zero reference potential.

9. A method as defined in claim 8 further comprising forming the square wave portion with a leading edge having a relatively rapid rise time and with a trailing edge having a relatively slower fall time.

10. An apparatus for blocking the pain caused by a traumatic or medical procedure on a patient with the use of transcutaneous electrical nerve stimulation, comprising:

source means for supplying a source of relatively high DC voltage;

voltage control means connected to said source means and receptive of the relatively high DC voltage and operative for supplying a controllable level of the DC voltage;

an output transformer means having a primary and a secondary winding, the primary winding connected to said voltage control means and receptive of the controlled DC voltage level supplied by said voltage control means, the transformer means operatively inducing in the secondary winding an electrically isolated output signal of approximately the same frequency as the signal in the primary winding and with an amplitude characteristic proportional t the amplitude characteristic of the signal in the primary winding;

oscillator means operative for generating a square wave oscillator signal;

power driver means connected to the other end of said primary winding of said output transformer means, the power driver means receptive of said square wave oscillator signal and operative for switching current through the primary winding at a frequency related to the frequency of the oscillator square wave signal;

the secondary winding of said transformer means supplying an output signal in response to the conduction of the power driver means, the output signal being a wave form which includes a square wave portion of one polarity having a leading edge with a relatively rapid rise time and a trailing edge with a relatively slower fall time and a pulse portion of the opposite polarity; and

a pair of electrodes connected to the secondary winding of said output transformer means for conducting the output signal to the skin of a patient.

11. Apparatus as defined in claim 10, further comprising:

adjustment means connected to said oscillator means and operative for adjusting the frequency of the oscillator square wave signal.

12. Apparatus as defined in claim 11, further comprising:

adjustment means connected to said voltage control means and operative for adjusting the level of the controlled voltage.

13. Apparatus as defined in claim 11 wherein said square wave oscillator signal is adjustable within a range of 2.5 kilohertz to 60 kilohertz.

14. Apparatus as defined in claim 10 wherein the power driver means conducts current through the primary winding during one state of the square wave oscillator signal and does not conduct current through the primary winding during the other state of the square wave oscillator signal, and said square wave signal has a predetermined frequency within the range of 2.5 kilohertz to 60 kilohertz.

15. Apparatus as defined in claim 14 further comprising:

a second pair of electrodes connected in parallel with said first electrodes.

16. Apparatus as defined in claim 14 further comprising:

a first output channel comprising the source means, the voltage control means, the output transformer means, the oscillator means, the power driver means, and the pair of electrodes, all as first aforesaid; and

a second output channel comprising the first said source means, a second said voltage control means, a second said output transformer means, a second said oscillator means, a second said power driver means, and a second pair of electrodes.

17. A method for blocking the pain caused by a traumatic or medical procedure on a patient with the use of transcutaneous electrical nerve stimulation, comprising the steps of:

(a) generating a high frequency series of electrical pulses;

(b) adjusting the frequency of the pulses to a relatively high rate;

(c) adjusting the intensity of the pulses to a relatively low level;

(d) applying said generated pulses to a desired area on a patient'"'"'s body;

(e) adjusting the intensity of the pulses to a desired level;

(f) adjusting the frequency of the pulses to a relatively lower frequency until the patient begins to perceive a nerve sensation; and

(g) continuing to adjust the frequency downwardly as necessary throughout the procedure to maintain the nerve sensation.

18. A method as defined in claim 17 wherein the high frequency electrical pulses can be adjusted within the frequency range of 2.5 to 60 kilohertz.

19. A method as defined in claim 17 further including forming the high frequency electrical pulses to include a square wave portion and an opposite polarity pulse centered about a zero reference potential.

20. A method as defined in claim 19 further comprising forming the square wave portion with a leading edge having a relatively rapid rise time and with a trailing edge having a relatively slower fall time.