Digital automated current perception threshold (CPT) determination device and method

• US 5,806,522 A
• Filed: 08/15/1995
• Issued: 09/15/1998
• Est. Priority Date: 08/15/1995
• Status: Expired due to Term

• Current Assignee: Jefferson Jacob Katims
• Original Assignee: Jefferson Jacob Katims
• Inventors: Katims, Jefferson Jacob
• Primary Examiner(s): Millin, Vincent
• Assistant Examiner(s): WIELAND, ROBERT N
• Application Number:
  US08/515,302
• Time in Patent Office: 1,127 Days
• Field of Search: 128/733, 128/740, 128/741, 128/744, 128/779, 128/630
• US Class Current: 600/554
• CPC Class Codes: A61B 5/4824 Touch or pain perception evaluation A61B5/4821 takes precedence
• CPC Class Codes: G16H 20/30 relating to physical therapies or activities, e.g. physiotherapy, acupressure or exercising
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems

Abstract

A method of quantitatively determining and recording constant alternating current conscious perception threshold or current conscious pain perception threshold for the purposes of determining normality or abnormality or corresponding or related anticipated therapy or drug therapy or for monitoring nerve regeneration or functional integrity, comprising the steps of, specifically placing electrodes on the patient according to a predetermined test involving a patient'"'"' conscious response, activating a power source, using an integral micro-controller operated digital stimulator, that monitors conscious responses and does not respond to unconscious or vegetative responses and computes the threshold value and registers it after application of a constant current having regard for frequency, waveform, intensity, duration of presentation, and electrode size, calculating and registering data which may be determinative or non-determinative as produced by the integral micro-controller operated unit.

Claims

1. A method of quantitatively determining and recording constant alternating current conscious perception threshold or current conscious pain perception threshold for the purposes of determining normality or abnormality or corresponding or related anticipated therapy or drug therapy or for monitoring nerve regeneration or functional integrity,

comprising,

specifically placing electrodes on the patient according to a predetermined test involving a patient'"'"'s conscious response,

activating a power source using an integral micro-controller operated digital stimulator that monitors conscious responses that are more effective as data for analysis as compared to unconscious or vegetative responses and that computes the threshold value and registers it after application of a constant current having regard for frequency, waveform, intensity, duration of presentation, and electrode size, and

calculating and registering data which may be determinative or non-determinative as produced by the integral micro-controller operated unit.

2. The method of claim 1 and a further included step, when automatically noted data is non-determinative,

of varying the constant alternating current intensity, and a further step of again monitoring responses and computing the threshold value and registers it,

effecting automatic comparison with normal statistical data, registering determination of diagnosis based on said comparison,

and registering suggested or recommended treatment.

3. The method of claims 1 or 2 and varying the amperage of the constant alternating current.

4. The method of claims 1 or 2 and varying the frequency of the constant alternating current.

5. The method of claims 1 2 or 3 presenting said electrical current stimuli in a series of steps and including a rest interval between at least between two steps.

7. The method of any of the preceding claims and varying the size of the area of contact being stimulated.

8. A diagnostic method which includes determining separate perception thresholds at frequency levels related to the major nerve subpopulations that comprise the typical sensory nerve of a body

comprising the steps of first testing in accordance with claim 1 using a first predetermined frequency and varying the amperage of the constant current then, testing in accordance with the steps of claim 1 using a second predetermined frequency and varying the amperage of the constant current

effecting automatic comparison with normal data, registering determination of diagnosis based on said comparison

and registering suggested or recommended treatment.

6. The method of any of the preceeding claims and varying the placement site of the electrodes.

9. An apparatus for quantitative determination and recording of conscious perception thresholds for the purpose of determining diagnosis of normalcy or abnormality and producing visual record of suggested or recommended treatment comprising a power source connected to,

a digital micro-controller including a control panel, a display screen associated therewith,

circuitry for the production of an alternating constant current of high voltage compliance, electrodes connected to said circuitry,

said electrodes being adapted to be applied cutaneously to a patient or an orifice of a patient, said micro-controller including manual operating means for setting up automatic testing operation including varying output parameters encompassing varying constant alternating current amperage intensity, varying frequency, varying waveform, and varying duration of presentation, and for selecting pre-determined tests involving conscious perception including ranges of intensity and ranges of frequency and testing sites and medical conditions,

said micro-controller including a programmed read only memory chip programmed with statistical data related to normalcy, abnormalities and testing procedures,

whereby a clinician, technician, or an instructed patient may apply the electrodes to a cutaneous site, activate the power source, set up a test procedure, cause the application of current stimuli, record obtained data, determine conscious response threshold, produce automatic or classification comparison of conscious response threshold perception with regard to programed data, determination of diagnosis and suggested treatment.

10. An apparatus as in claim 9 where in said control panel includes a display screen, a power control means, a frequency selector means, a manual test mode selection means, an automatic mode selection means, a manual intensity control means, automatic intensity control means.

11. An apparatus for the accurate production of a controlled alternating constant current output from a voltage input for producing said controlled alternating constant current over a wide voltage compliance range without excessive power supply dissipation or cross-over distortion suitable for application in testing equipment for determining threshold perception of applied stimulus comprising an initial single-ended to push/pull transconductance stage consisting of an opamp, a novel bias network, 2 MOSFETs and a common sensing resistor, which produces 2 half currents, one being sunk, one being sourced, and capable of being referenced to the high voltage supplies, said apparatus also including two current mirrors, one referenced to the top supply and one referenced to the bottom supply, said apparatus being capable of extremely accurate reproduction of current and very high voltage capability and said mirrors being constructed with opamps, a single MOSFET, and two precisely matched or ratioed resistors.

12. A method of quantitatively determining and recording constant alternating current perception threshold or current pain perception threshold for the purposes of determining normality or abnormality or corresponding or related anticipated therapy or drug therapy or for monitoring nerve regeneration or functional integrity, comprising

specifically placing electrodes on the patient according to a predetermined test, activating a power source using an integral micro-controller operated digital stimulator that monitors responses and that computes the threshold value and registers it after application of a constant current having regard for frequency, waveform, intensity, duration of presentation, and electrode size,

calculating and registering data which may be determinative or non-determinative as produced by the integral micro-controller operated unit, and if automatically noted data is non-determinative,

varying the constant alternating current intensity, again monitoring responses and computing the threshold value and registering it, effecting automatic comparison with normal statistical data, registering determination of diagnosis based on said comparison and registering suggested or recommended treatment.

13. A method of quantitatively determining and recording constant alternating current perception threshold or current pain perception threshold for the purposes of determining normality or abnormality or corresponding or related anticipated therapy or drug therapy or for monitoring nerve regeneration or functional integrity, comprising,

specifically placing electrodes on the patient according to a predetermined test, activating a power source using an integral micro-controller operated digital stimulator that monitors responses and that computes the threshold value and registers it after application of a constant current having regard for frequency, waveform, intensity, duration of presentation, and electrode size,

calculating and registering data which may be determinative or non-determinative as produced by the integral micro-controller operated unit, and varying the amperage of the constant alternating current.

14. A method of quantitatively determining and recording constant alternating current perception threshold or current pain perception threshold for the purposes of determining normality or abnormality or corresponding or related anticipated therapy or drug therapy or for monitoring nerve regeneration or functional integrity, comprising,

specifically placing electrodes on the patient according to a predetermined test, activating a power source using an integral micro-controller operated digital stimulator that monitors responses and that computes the threshold value and registers it after application of a constant current having regard for frequency, waveform, intensity, duration of presentation, and electrode size,

calculating and registering data which may be determinative or non-determinative as produced by the integral micro-controller operated unit and varying the frequency of the constant alternating current.

15. A method of quantitatively determining and recording constant alternating current perception threshold or current pain perception threshold for the purposes of determining normality or abnormality or corresponding or related anticipated therapy or drug therapy or for monitoring nerve regeneration or functional integrity, comprising,

specifically placing electrodes on the patient according to a predetermined test, activating a power source using an integral micro-controller operated digital stimulator that monitors responses and that computes the threshold value and registers it after application of a constant current having regard for frequency, waveform, intensity, duration of presentation, and electrode size, calculating and registering data which may be determinative or non-determinative as produced by the integral micro-controller operated unit and presenting said electrical current stimuli in a series of steps and including a rest interval between at least two steps.

16. A method of quantitatively determining and recording constant alternating current perception threshold or current pain perception threshold for the purposes of determining normality or abnormality or corresponding or related anticipated therapy or drug therapy or for monitoring nerve regeneration or functional integrity, comprising,

specifically placing electrodes on the patient according to a predetermined test, activating a power source using an integral micro-controller operated digital stimulator that monitors responses and that computes the threshold value and registers it after application of a constant current having regard for frequency, waveform, intensity, duration of presentation, and electrode size,

calculating and registering data which may be determinative or non-determinative as produced by the integral micro-controller operated unit and varying the placement site of the electrodes.

17. A method of quantitatively determining and recording constant alternating current perception threshold or current pain perception threshold for the purposes of determining normality or abnormality or corresponding or related anticipated therapy or drug therapy or for monitoring nerve regeneration or functional integrity, comprising,

specifically placing electrodes on the patient according to a predetermined test, activating a power source using an integral micro-controller operated digital stimulator that monitors responses and that computes the threshold value and registers it after application of a constant current having regard for frequency, waveform, intensity, duration of presentation, and electrode size,

calculating and registering data which may be determinative or non-determinative as produced by the integral micro-controller operated unit and varying the size of the area of contact being stimulated.

18. A double blind method of quantitatively determining and recording constant alternating current perception threshold or current pain perception threshold for the purposes of determining normality or abnormality or corresponding or related anticipated therapy or drug therapy or for monitoring nerve regeneration or functional integrity, comprising,

specifically placing electrodes on the patient according to a predetermined test, activating a power source using an integral micro-controller operated digital stimulator that monitors responses and that computes the threshold value and registers it after application of a constant current having regard for frequency, waveform, intensity, duration of presentation, and electrode size, calculating and registering data which may be determinative or non-determinative as produced by the integral micro-controller operated unit

wherein neither the operator nor the patient know the exact stimulation output parameters of the test device during the testing sequence comprising

(a) presenting a first test to the patient;

(b) presenting a non-test rest period to the patient;

(c) presenting a second test to the patient;

one of said tests being a true test with device output stimulation and the other of said tests being a false or placebo test without device output stimulation;

(d) inquiring of the patient whether the patient could discriminate between sensations perceived from the first and second tests by indicating which one felt stronger;

(e) if the patient'"'"'s response indicates that the stronger stimulus was perceived during the true test in which the device output stimulation was being presented, then presenting the testing sequence again at a lower device output stimulation intensity, or if the patient'"'"'s response indicates any inability to perceive any difference between the two tests in the testing sequence or indicates that the stronger stimulus was perceived during the false test without device output stimulation, then presenting the testing sequence again at a higher device output stimulation intensity and

(f) repeating steps (a)-(e).

19. A diagnostic method which includes determining separate perception thresholds at frequency levels related to the major nerve subpopulations that comprise the typical sensory nerve of a body comprising

(a) testing in accordance with a method of quantitatively determining and recording constant alternating current perception threshold or current pain perception threshold for the purposes of determining normality or abnormality or corresponding or related anticipated therapy or drug therapy or for monitoring nerve regeneration or functional integrity, comprising, specifically placing electrodes on the patient according to a predetermined test, activating a power source using an integral micro-controller operated digital stimulator that monitors responses and that computes the threshold value and registers it after application of a constant current having regard for frequency, waveform, intensity, duration of presentation, and electrode size, calculating and registering data which may be determinative or non-determinative as produced by the integral micro-controller operated unit

using a first predetermined frequency and varying the amperage of the constant current,

(b) testing in accordance with the method of (a) except using a second predetermined frequency and varying the amperage of the constant current,

(c) effecting automatic comparison with normal data,

(d) registering determination of diagnosis based on said comparison and

(e) registering suggested or recommended treatment.

20. An apparatus for quantitative determination and recording of perception thresholds for the purpose of determining diagnosis of normalcy or abnormality and producing visual record of suggested or recommended treatment comprising

a power source connected to, a digital micro-controller including a control panel,

a display screen associated therewith, circuitry for the production of an alternating constant current of high voltage compliance, electrodes connected to said circuitry,

said electrodes being adapted to be applied cutaneously to a patient or an orifice of a patient, said micro-controller including manual operating means for setting up automatic testing operation including varying output parameters encompassing varying constant alternating current amperage intensity, varying frequency, varying waveform, and varying duration of presentation, and for selecting predetermined tests involving ranges of intensity and ranges of frequency and testing sites and medical conditions,

said micro-controller including a programmed read only memory chip programmed with statistical data related to normalcy, abnormalities and testing procedures,

whereby a clinician, technician, or an instructed patient may apply the electrodes to a cutaneous site, activate the power source, set up a test procedure, cause the application of current stimuli, record obtained data, determine threshold, produce automatic or classification comparison of threshold perception with regard to programed data, determination of diagnosis and suggested treatment, wherein said control panel includes a display screen, a power control means, a frequency selector means, a manual test mode selection means, an automatic mode selection means, a manual intensity control means and automatic intensity control means.