Apparatus for measuring the transport time of nerve signals

• US 5,313,956 A
• Filed: 08/04/1992
• Issued: 05/24/1994
• Est. Priority Date: 12/04/1990
• Status: Expired due to Fees

• Current Assignee: Dorsograf AB
• Original Assignee: Dorsograf AB
• Inventors: Gransberg, Lennart, Knutsson, Evert
• Primary Examiner(s): HINDENBURG, MAX F
• Application Number:
  US07/915,994
• Time in Patent Office: 658 Days
• Field of Search: 128/732, 128/741, 128/734, 128/783, 128/795, 128/797, 128/905
• US Class Current: 600/554
• CPC Class Codes: A61B 5/389 Electromyography [EMG]
• CPC Class Codes: A61B 5/407 Evaluating the spinal cord A61B5/4896 takes precedence

Abstract

The invention relates to apparatus which includes stimulating electrodes (2,3) through which electrical signals are applied to an extremity of a patient (1). Detecting electrodes (30,40) are disposed along the patient'"'"'s spine and on the crown of the patient'"'"'head. The apparatus also includes signal amplifiers (7,8), a loudspeaker (9) or the like to which an amplified signal is applied for physiological feedback purposes, an A/D-converter and a computer (20). Samples of signals are collected so as to obtain from the distributed electrodes means value curves from which the transport time of the nerve signals from respective extremities can be determined.

Claims

1. An apparatus for measuring the transport time of nerve signals of a patient, said apparatus comprising:

(a) a plurality of stimulating electrodes capable of transmitting an electrical signal to the patient;

(b) a plurality of detecting electrode-pairs adapted for attachment to the patient'"'"'s skin;

(c) amplifying means connected to said electrode-pairs capable of amplifying the electrical signals detected by said electrode-pairs;

(d) an A/D-converter capable of receiving the amplified electrical signals generated by said amplifying means;

(e) a computer capable of processing the amplified electrical signals received by said A/D-converter and storing said signals as numerical sequences at specific time points;

(f) means for excluding select numerical sequences;

(g) means for summating the numbers in the numerical sequences that are not excluded in step (f);

(h) means for determining the mean values for said summated numbers; and

(i) means for signalling the output signals of said amplifying means to the patient'"'"'s consciousness.

2. The apparatus according to claim 1 wherein said means for signalling to the patient'"'"'s consciousness comprises a sound generator.

3. The apparatus according to claim 2 wherein said sound generator is a loudspeaker or headphones.

4. The apparatus according to claim 1 wherein said means for signalling to the patient'"'"'s consciousness comprises an image generator.

5. The apparatus according to claim 4 wherein said image generator is an oscilloscope.

6. The apparatus according to claim 1 wherein said electrode-pairs comprise an electrode-pair adapted for attachment to the crown of the patient'"'"'s head, and from 4 to 9 electrodes adapted for attachment along the patient'"'"'s spine.

7. The apparatus according to claim 1 wherein the signals that are transmitted by said stimulating electrodes are stored and recorded separately.

8. A method of measuring the transport time of nerve impulses as the nerve impulses travel from an extremity of a patient to the cortex of said patient, said method comprising:

(a) attaching a plurality of stimulating electrodes capable of transmitting an electrical signal to said patient;

(b) attaching a plurality of detecting electrode-pairs to said patient;

(c) amplifying the electrical signals detected by said electrode-pairs;

(d) transmitting the amplified electrical signals of (c) to an A/D-converter;

(e) processing and storing the amplified electrical signals received by said A/D converter in a computer as numerical sequences at specific time points;

(f) excluding select numerical sequences;

(g) summating the numbers in the remaining numerical sequences;

(h) determining the mean values of said summated numbers;

(i) signalling the amplified signals to said patient.

9. The method according to claim 8 wherein said stimulating electrodes are attached to said patient'"'"'s extremities.

10. The method according to claim 8 wherein said detecting electrode-pairs are attached to said patient'"'"'s cortex.

11. The method according to claim 8 wherein said detecting electrode-pairs are attached to said patient'"'"'s spine.

12. The method according to claim 11 wherein said detecting electrode-pairs are attached at nine or more different locations on said patient'"'"'s spine.

13. The method according to claim 8 wherein said amplified signals are signalled to said patient audibly, visually or a combination thereof.

14. A method of comparing the nerve impulses generated by the left side of a patient with the nerve impulses generated by the right side of a patient, said method comprising:

(a) attaching a plurality of stimulating electrodes capable of transmitting an electrical signal to the left side of said patient;

(b) attaching a plurality of stimulating electrodes capable of transmitting an electrical signal to the right side of said patient;

(c) attaching a plurality of detecting electrode-pairs to said patient;

(d) alternately activating the stimulating electrodes so that while one side of said patient is being stimulated the opposite side of said patient is not being stimulated;

(e) amplifying the electrical signals detected by said electrode-pairs;

(f) transmitting the amplified electrical signals of (e) to an A/D-converter;

(g) processing and storing the amplified electrical signals received by said A/D-converter in a computer as numerical sequences at specific time points;

(h) excluding select numerical sequences;

(i) summating the numbers in the remaining numerical sequences;

(j) signalling the amplified signals to said patient.

15. The method according to claim 14 wherein the electrical signals generated by the right side of said patient are stored and processed separately from the electrical signals generated by the left side of said patient.

16. The method according to claim 14 wherein said stimulating electrodes are attached to said patient'"'"'s extremities.

17. The method according to claim 14 wherein said detecting electrode-pairs are attached to said patient'"'"'s cortex.

18. The method according to claim 14 wherein said detecting electrode-pairs are attached to said patient'"'"'s spine.

19. The method according to claim 18 wherein said detecting electrode-pairs are attached to said patient'"'"'s spine at nine or more different locations.

20. The method according to claim 14 wherein said amplified signals are signalled to said patient audibly, visually, or a combination thereof.