Muscle tone

• US 5,158,080 A
• Filed: 01/23/1992
• Issued: 10/27/1992
• Est. Priority Date: 11/08/1990
• Status: Expired due to Term

• Current Assignee: Inspire Medical Systems, Inc.
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Kallok, Michael J.
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US07/824,308
• Time in Patent Office: 278 Days
• Field of Search: 128/848, 128/421, 128/783
• US Class Current: 607/42
• CPC Class Codes: A61N 1/3601 of respiratory organs

Abstract

An apparatus for and method of improving muscle tone of a patient using chronic sub-tetanic electrical stimulation. For patients suffering from obstructive sleep apnea, for example, the muscles of the upper airway are provided the chronic stimulation to mitigate or prevent the adverse medical condition caused in part by excessively flaccid muscle tissue around and in the airway.

A stimulation generator supplies pulses to the muscle to be treated through insulated leads which are coupled to electrodes directly in contact with the appropriate neuro-muscular tissue. The output of the stimulation generator is adjusted to a frequency of sufficiently low level as to prevent fused tetanic contraction of the stimulated muscle. The adjustment may be made manually by attending medical personnel or may be done automatically using electrodes to sense the tension of the stimulated muscle. In the automatic mode, the sensing system insures the stimulation frequency level is decreased below the threshold of muscle tetanus.

Stimulation may be accomplished at a particular site or may be multiplexed to a number of sites. Chronic stimulation will enhance muscle tone to an individual degree and then will simply maintain the desired status.

Claims

1. A method of treating obstructive sleep apnea comprising:

a. coupling electrodes to muscle tissue of the upper airway; and

b. chronically stimulating said muscle tissue at a stimulus level of less than that producing fused tetanic contraction.

2. A method according to claim 1 further comprising:

chronically monitoring said muscle tissue of said upper airway for occurrence of fused tetanic contraction.

3. A method according to claim 2 further comprising:

decreasing frequency of said stimulation of said muscle tissue if said chronically monitoring step indicates fused tetanic contraction.

4. An apparatus for treating obstructive sleep apnea comprising:

a. an electrode coupled to muscle tissue of the upper airway of a patient;

b. means coupled to said electrode for supplying stimulation pulses to said muscle tissue via said electrode;

c. means coupled to said muscle for sensing tetanic contraction of said muscle tissue; and

d. means coupled to said sensing means and said supplying means for adjusting said stimulation pulses in response to said supplying means to ensure that said stimulation pulses do not stimulate fused tetanic contraction of said muscle tissue.

5. An apparatus according to claim 4 wherein said adjusting means further comprises means for decreasing the frequency of said stimulation pulses.

6. An apparatus according to claim 5 further comprising a plurality of electrodes coupled to said supplying means.

7. An apparatus according to claim 6 wherein said adjusting means further comprises means for increasing said frequency of said stimulation pulses.