Patterned electrical tissue stimulator

• US 4,390,023 A
• Filed: 04/30/1981
• Issued: 06/28/1983
• Est. Priority Date: 04/30/1981
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Rise, Mark T.
• Primary Examiner(s): Kamm, William E.
• Assistant Examiner(s): Shein, Mitchell J.
• Application Number:
  US06/259,099
• Time in Patent Office: 789 Days
• Field of Search: 128/419 P, 128/419 F, 128/419 E, 128/419 G, 128/421, 128/422, 128/423, 128/795, 128/796, 128/1 B, 128/419 R, 364/413, 364/770
• US Class Current: 607/66
• CPC Class Codes: A61N 1/36021 for treatment of pain

Abstract

A patterned electrical tissue stimulator includes a current source and analog multiplexers connected to an array of electrodes attached to the body. Microprocessor control of the multiplexer and the current source provides automatic selection of electrode stimulation pairs whereby spatial patterns of electrical stimulation are produced. Temporal summation and temporal patterns of electrical stimulus are provided through microprocessor control of the current source.

Claims

1. A portable automatically controlled electrical tissue stimulator comprising:

means for producing electrical stimulation current, the polarity of said current controllable by a current control signal;

a plurality of electrodes for attachment in an array to a patient to be treated;

multiplexing means operatively connected between said current means and said electrodes, and responsive to a multiplexing signal for selectively connecting any pair of electrodes to said current means; and

presettable automatic control means including memory means for storing presettable digitally encoded information indicative of a desired sequence of electrode pair connections and a desired number of current pulses to be applied to each of the pairs connected in the sequence and further including means responsive to said information stored in said memory means to produce said multiplexing signal and said current control signal to cause said electrodes to be sequentially connected to said current means automatically and stimulation current pulses of alternating polarity to be delivered to said pairs of said electrodes automatically.

3. An apparatus according to claim 1, wherein said presettable automatic control means includes means for causing a plurality of electrode pairs to be connected in sequence to said means for producing electrical stimulation current, within a 4 msec period, so that the electrical stimulation delivered to each of said electrode pairs is temporarily indistinguishable to the patient.

4. An apparatus according to claim 1, wherein each of the current pulses produced by said means for producing said stimulation current are generated at an intensity level substantially equal to or less than the level of human perception.

5. An apparatus according to claim 4, wherein said presettable automatic control means includes means for causing a plurality of said current pulses to be delivered to a connected electrode pair within a duration of time short enough to cause said pulses to be temporarily summed in the stimulated tissue.

2. An apparatus according to claim 2 wherein said presettable automatic control means comprises a microprocessor.