WO2002028477A1

WO2002028477A1 - Apparatus for applying electronic treatment

Info

Publication number: WO2002028477A1
Application number: PCT/GB2000/003838
Authority: WO
Inventors: Ifor Capel; Bernard Lim
Original assignee: Spes Patents Limited
Priority date: 2000-10-05
Filing date: 2000-10-05
Publication date: 2002-04-11
Also published as: AU2000275456A1

Abstract

An apparatus (10) for applying electronic treatment comprises a controller (18) and switch (16) which control an output from a current source (14) applied to a patient. A memory (20) stores a number of treatment loaded in a one-time procedure from a smart card (28). Control can thus be maintained over the patient's usage of the apparatus. The switch (16) comprises an electronically-controllable switch. The controlled is also arranged, at least in some embodiments, to disable the apparatus for a predetermined period between usages.

Description

APPARATUS FOR APPLYING ELECTRONIC TREATMENT

The present invention is concerned with electronic treatment or electrotherapy, particularly but not exclusively transcranial electrotherapy (TCET), and in particular to a method and apparatus for safely applying treatment to a patient in circumstances where supervision by medical personnel is not necessarily available.

The principles of TCET are set out particularly in US patent 4,646,744 and International patent application WO91/06340. The first document outlines the principles of TCET and emphasizes the distinction between this technique and that of transcutaneous electrical nerve stimulation (TENS), electro-acupuncture and invasive electrical treatments. The second document describes a number of refinements developed in respect of the TCET technique. In particular, the second document describes the low level currents required to obtain effective treatment - of the order of a few microamps (μA).

Unfortunately the stable and accurate delivery of such TCET treatment has proved extremely difficult to provide on a large scale and cost-effective basis.

It is an object of the present invention to ameliorate the above disadvantages.

According to a first aspect of the present application, there is provided apparatus for applying electronic treatment to a human being, the apparatus comprising: a waveform generator for applying electrical waveforms to the human being; a controller for controlling the pulse generator to provide a predetermined number of treatments, wherein at least the number of treatments are predeterminable by an external device. In the first aspect of the present invention the apparatus provided is concerned with addressing the problem of self medication either by the owner of the TCET device or somebody else. Since patients can become dependent upon the therapeutic effects of TCET, there is a need to control its delivery to the patient. Typically, a pharmaceutical treatment which may be habit-forming will only be administered by qualified medical personnel either to in- or out-patients at a medical facility. This solution can be used, and in certain circumstances may be appropriate, in the application of TCET or other treatments in accordance with embodiments of the present invention. However, the present inventors have appreciated that due to the electronic nature of the treatment delivery apparatus, it is possible to provide such apparatus to the patients for use unsupervised (at least for given time periods) in their own home, etc. The benefits of so doing are numerous. The reduction in workload on medical staff and the improved use of resources at medical facilities will save medical authorities substantial sums of money. The patient is also spared the inconvenience and expense of a long stay in hospital or the inconvenience and expense of frequent trips to a medical facility for treatment. Because the patients are provided with apparatus which can be used at home or place of work, they will be more readily able to fit the treatment schedule in around other commitments, thus severely reducing the likelihood of missed treatments or treatments delivered at non-optimal time intervals. Patients receiving TCET are often mobility-impaired, further reducing the necessity of travelling to receive treatment.

In a preferred embodiment of this aspect of the present invention the apparatus is further provided with a smart card reader which can read a smart card which carries instructions for providing a number of treatments to the patient. While it is possible to load dosages onto the apparatus at a hospital or other healthcare facility such as a pharmacy, this entails a degree of inconvenience to the patient. While in certain circumstances completion of a set of treatments will require further consultation with a physician or other medical personnel, this may not always be necessary. By providing a further set of dosages on a smart card the card may be delivered to the users (possibly following a telephonic consultation with their doctor, etc.). In a further preferred embodiment the series of dosages stored on the smart card are downloaded in a single operation to a memory within the apparatus. The smart card is then effectively "wiped" and may be discarded. The benefit of this arrangement is that the patient does not need to keep hold of two pieces of equipment, namely the apparatus and the smart card, while the benefits of the smart card, such as control over the number of treatments, are maintained.

As an alternative to a smart card or other physical source of dosages, in another embodiment messages may be downloaded from a remote computer, for example via a telephone line or the internet.

According to a second aspect of the present invention invention, there is provided a method of applying electronic treatment to a human being using an electronic treatment apparatus, wherein at least the number of treatments are predetermined by a further device external to the electronic treatment apparatus.

A problem addressed by third and fourth aspects of the present invention is that of providing the low-level currents required by TCET and as set out in WO91/06340. The present inventors have attempted numerous techniques for providing these currents to a patient (typically a positive current of around 12 μA, a negative current of less than 1 μA and a zero current). Various circuits have been provided by use of operational amplifiers, digital to analogue converters and so on. They have consistently and universally failed to cost-effectively provide the required currents to the variable impedance which a patient's head provides. This is typically in the range of 50 kΩ to 220 kΩ.

A third aspect of the present invention provides apparatus for applying electronic treatment to a human being, the apparatus comprising a waveform generator including at least a first signal generator and a first electronically-controllable switch, the first electronically-controllable switch having at least a first switched channel input, a switched channel output and a control electrode, whereby the first switched channel input is connected or disconnected from the switched channel output in response to a signal applied to the control electrode; the first signal generator having an output coupled to the switched channel input of the electronically-controllable switch; the switched channel output of the electronically-controllable switch being connectable to electrodes for connection to the human being, the apparatus further comprising a controller having an output connected to the control electrode of the electronically- controllable switch.

A fourth aspect of the present inventions provides method of applying electronic treatment to a human being using an electronic treatment apparatus, the method comprising generating at least one signal and controlling its application to the human being using an electronically-controlled switch.

The use of electonically-controllable switches such as analogue switches in conjunction with an accurate low-level current has been proved to provide accurate and reliable delivery of the necessary source (or sink) currents.

A problem addressed by fifth and sixth aspects of the present invention is that of preventing patients from over-treating themselves. In certain circumstances patients could become psychologically dependent on TCET and there is a risk that the user will receive too many treatments over too short a period of time. Additionally, those in chronic pain may be tempted to apply too many treatments in the hope of further alleviation of that pain.

A fifth aspect of the invention thus provides apparatus for applying electronic treatment to a human being, the apparatus comprising: a waveform generator for applying electrical waveforms to the human being; a controller for controlling the waveform generator to provide a predetermined number of treatments, the controller being adapted to disable the apparatus for a predetermined time period between treatments. A sixth aspect of the invention provided method of applying electronic treatment to a human being using an electronic treatment apparatus, the method comprising disabling the treatment apparatus for a predetermined time after a treatment is applied.

In a preferred embodiment the lock-out period is 3 hours. In another preferred embodiment the predetermined disabled period may be increased or decreased for a particular patient. The necessary prescription may be loaded by way of a smart card, other data carrier or remotely as discussed above in respect of the first aspect of the present invention.

The present invention will now be described by way of example, with reference to the accompanying drawings, in which:

Figure 1 shows a graph of current against time for the output current waveforms provided by an embodiment of the present invention;

Figure 2 shows a block diagram of the component parts of apparatus in accordance with an embodiment of the invention;

Figure 3 shows a more detailed block schematic diagram of the circuitry used in such apparatus; and

Figure 4 shows a flow chart illustrating operation of the apparatus.

As set out in prior art document WO91/06340 the waveform provided is preferably an asymmetric one having a large, but short positive-going pulse followed by a much smaller but longer negative-going pulse. In one embodiment net charge can be zero or a predetermined value close to zero. Following the negative-going pulse there is a period of zero current or a predetermined current value close to zero. Figure 1 shows a waveform for which the following table gives the values and tolerances of various currents and times.

This combination of positive and negative pulses are typically provided in trains of several hundred pulse pairs. In one embodiment each train is 750 pulse-pairs long and a treatment typically comprises 39 pulse trains.

While the figures show overshoot currents (i2, i3 and i5), and the size of such currents will usually be specified, it is often the type of overshoot rather than its magnitude that is of concern. Cnsequently no values are given for the overshoot values but the skilled person will be able to design circuitry that provides acceptable performance in this respect.

Figure 2 shows a block schematic diagram of a TCET apparatus in accordance with an embodiment of the present invention. The apparatus is shown overall at 10 connected to a patient 12 via his earlobes. Suitable electrodes are described in WO 91/06340. The apparatus comprises current source 14, a switch 16, a controller (CNTL) 18, a memory 20 and a card reader 22. An IC card for attachment to, and reading by, the card reader 22 is indicated at 28. The CNTL18 includes a clock CLK 26 and a counter (CNT) 24 which are used in the management of the disablement period discussed below. The apparatus will also include a regulated power supply, display circuitry and displa ed- driver circuitry, other visual and audible warnings, one or more buttons or switches to allow for user input and so on, but these are not shown in this diagram for reasons of clarity.

When power is applied to the unit the current source 14 generates the positive-going current and the negative-going current which are to be applied at various times to the patient 12. While a current source is shown, the current could equally be provided by a current sink or a supervisory controller (passive) device and so on. Lines carrying these currents are connected to a switch 16. In a preferred embodiment the switch comprises a semiconductor analogue switch but may comprise a number of suitable switching devices including field effect transistors and so on. The switch 16 applies the positive- going current, the negative-going current or a zero current (preferably a short circuit) to the user 12 under the control of CNTL 18. CNTL 18 is pre-programmed with certain limit parameters and actual parameters for use may then be derived from memory 20. For example, the controller 18 is programmed with a maximum number of pulses which may be used in each train. The memory 20 then stores a number less than or equal to this number and then, in operation, the control unit causes the correct number of pulses to be applied. One particularly significant parameter is the disabled period following a treatment. This is the time during which, following delivery of a treatment, the unit will refuse to operate. In a preferred embodiment this period is 3 hours. However, it may be that a prescribing physician wants this period to be longer. In this case, this element of the prescription (along with other defining parts of the treatment waveform) are stored on IC card 28 for storage in memory 20.

In accordance with another embodiment, special units are provided that have a smaller, or zero, disabled period. These are for use under medical supervision and are preferably identifiable as such, for example by being a different colour.

Figure 3 shows a more detailed block schematic diagram of the circuitry 50 for providing an apparatus in accordance with an embodiment of the invention. A controller (CNTL) 52 is connected to a smart card reader 60, a set of switches 54, 56, 58, a set of light emitting diodes (LEDs) 64, 66, 68, an audible warning device 70 and a writable, non-volatile memory 72. The controller 52 is further connected to a liquid crystal display 74 (whose associated driver circuitry is omitted for clarity). In addition, the circuit comprises a positive current source 76 connected via an analogue switch 80 to an output terminal 84 and a negative current source 78 connected via an analogue switch 82 to the output terminal 84. The two analogue switches 80, 82 are controlled by output lines from the controller 52. The current sources 76, 78 also comprise error detection circuitry (such as inability to supply the specified current into the load impedance) which are connected to inputs to the controller 52.

These switches may have the function ON/OFF, START TREATMENT, tamper detection and so on. The LEDs will typically indicate POWER ON, DISABLED MODE, CONNECTION TO PATIENT OK and so on. The audible warning device 70 is used to indicate disconnection of the device from the patient during treatment (typically by means of a rapid increase in load impedance). The unit generates current waveforms such as shown in Figure 1 by connecting the outputs of current generators 76 and 78 to the output terminal 84. The liquid crystal display 74 will display information such as the time remaining in the present treatment and, in disabled mode, the time before a further treatment can commence.

Also shown in Figure 3 is a smart card 62 for insertion into the smart card reader 60. Such smart cards are programmed with the number of treatments to be provided to a given patient and these are downloaded in a one-time procedure for storage in the memory 72.

The analogue switch must be selected to switch quickly enough to satisfy the requirements set out in the table above. The other current generator and analogue switch arrangement operates in an analogous manner and its output is connected to patient electrode plug.

Figure 4 shows a flowchart illustrating the steps of operation in more detail. The routine starts at step S10 and proceeds to decision step S12 at which it is determined whether the unit is in lockout, or disabled mode. If the answer is yes then the countdown until the unit may be re-used is displayed at step SI 4. At step S 16 the LED that indicates disabled or lockout mode is flashed. The LEDs are preferably flashed to save battery energy. After step S16 processing returns to decision step S12. If the unit is not in lockout mode then processing proceeds to step SI 8 at which it is determined whether the patient requires treatment. This may be determined from the impedance value across the electrodes or in response to a START TREATMENT button. If treatment is not required then processing proceeds to decision step S20. This step determines whether the unit has been inactive for three minutes and, if yes, proceeds to end the routine at step S22. Provided the unit is in use processing proceeds from step S20 to step S12.

If treatment is determined to be required at step SI 8 then processing proceeds to step S24. The appropriate treatment, both in terms of the number of pulses and the number of pulse trains to be applied to the patient is retrieved from non-volatile memory 72. The parameters for the current treatment are thus set and processing proceeds to step S26. At this step the unit determines whether the connection to the patient is OK, typically by determining whether the impedance at the output terminal 84 (Figure 3) is in the range of 50 kΩ to 220 kΩ. If the connection is deemed not to be adequate then the disconnect LED is flashed at step S28. The audible warning device 70 (Figure 3) may also be sounded. Processing proceeds to decision step S30 at which it is determined whether the unit has been disconnected from the user for more than eight minutes. If the answer is yes then the unit enters lockout mode at step S32 and processing returns to step SI 2. If the unit has not yet been disconnected for eight minutes then processing proceeds to step S26 to determine whether the patient has corrected the disconnected state.

Assuming that the connection to the patient is OK then processing proceeds to step S34 at which it is determined whether more pulse trains are to be applied. Provided there is still at least one more pulse train to be applied processing proceeds to step S36. If no more pulse trains are to be applied then the unit enters lockout mode at step S32 and processing proceeds to step S12. Otherwise processing proceeds to step S36 at which the number of pulse trains remaining is decremented.

At step S38, following step S36, the controller determines whether there are more pulses to be applied in the current pulse train. If the answer is no then processing proceeds to step S26 at which the connection to the patient is tested once more. Assuming that more pulses are to be applied, processing proceeds to step S40 at which the number of pulses is decremented and processing proceeds to step S42. At step S42 the controller generates an output pulse such as the one described with reference to Figure 1. The output pulse will generally comprise a short positive-going pulse followed by a longer negative-going pulse and then a period at or close to zero volt. Once the pulse has been generated processing proceeds to step S38 at which the controller determines whether there are more pulses to be provided.

The apparatus is preferably tamper proof or very nearly so. In particular, it should be extremely difficult for a user to open the case of the apparatus and modify the circuitry or contents of memory within the case, without it being obvious to a subsequent inspector of the case that it had been tampered with. One technique is for the case to be provided with a tamper detection switch that can be connected to the controller 52.

Claims

CLAIMS:

1. Apparatus for applying electronic treatment to a human being, the apparatus

comprising: a waveform generator for applying electrical waveforms to the human being;

a controller for controlling the pulse generator to provide a predetermined number of treatments, wherein at least the number of treatments are predeterminable by an external device.

2. Apparatus as claimed in claim 1, wherein the external device is a smart card and the apparatus is further provided with a smart card reader.

3. Apparatus as claimed in claim 1, wherein the external device is a remote computer and the apparatus is further provided with a connection to that remote computer.

4. Apparatus as claimed in claim 1, claim 2 or claim 3, further comprising an internal storage device and whereby the controller is arranged to download data corresponding to a plurality of treatments from the external device.

5. Apparatus as claimed in claim 4, wherein the controller is arranged to download data corresponding to a plurality of treatments during a single download.

6. Apparatus as claimed in any one of the claims 1 to 5, wherein a minimum time interval between treatments is also predeterminable by the external device.

7. Apparatus as claimed in any one of the claims 1 to 5, wherein the apparatus is

arranged to be responsive only to a limited number of external devices.

8. Method of applying electronic treatment to a human being using an electronic treatment apparatus, wherein at least the number of treatments are predetermined by a further device external to the electronic treatment apparatus.

9. Method as claimed in claim 8, wherein a minimum time interval between treatments is also predetermined by the external device.

10. Method as claimed in claim 8 or claim 9, wherein the external device is arranged to be connected to the electronic treatment apparatus once to predetermine a plurality of treatments.

11. Apparatus for applying electronic treatment to a human being, the apparatus comprising a waveform generator including at least a first signal generator and a first electronically-controllable switch, the first electronically-controllable switch having at least a first switched channel input, a switched channel output and a control electrode, whereby the first switched channel input is connected or disconnected from the switched channel output in response to a signal applied to the control electrode; the first signal generator having an output coupled to the switched channel input of the electronically-controllable switch;

the switched channel output of the electronically-controllable switch being

connectable to electrodes for connection to the human being, the apparatus further comprising a controller having an output connected to the

control electrode of the electronically-controllable switch.

12. Apparatus as claimed in claim 11, further comprising a second signal generator connected to a switched channel input of a second electronically-controllable switch, a

switched channel output of the second electronically-controllable switch being connectable to an electrode for connection to the living being and a control electrode of the second electronically-controllable switch being connected to the controller.

13. Apparatus as claimed in claim 11 , wherein the first electronically-controllable switch has a second switched channel input whereby the switched channel output is connected to the first switched channel input or the second switched channel input in response to a signal applied to the control electrode, the apparatus further comprising a second signal generator coupled to the switched channel input of the second electronically-controllable switch.

14. Apparatus as claimed in claim 12 or claim 13, wherein the first signal generator and second signal generator are arranged to generate currents of opposite polarity.

15. Apparatus as claimed in claim 12, claim 13 or claim 14, wherein the first signal generator and the second signal generator are arranged to generate currents of differing

magnitude.

16. Apparatus as claimed in any one of claims 11 to 15, wherein the currents have

values not exceeding 35 μA.

17. Method of applying electronic treatment to a human being using an electronic treatment apparatus, the method comprising generating at leat one signal and controlling its application to the human being using an electronically-controlled switch.

18. Apparatus for applying electronic treatment to a human being, the apparatus comprising: a waveform generator for applying electrical waveforms to the human being; a controller for controlling the waveform generator to provide a predetermined number of treatments, the controller being adapted to disable the apparatus for a predetermined time period between treatments.

19. Apparatus as claimed in claim 18, wherein the predetermined time period is at least three hours.

20. Apparatus as claimed in claim 18 or claim 19, further comprising means for providing an extended predetermined time between treatments.

21. Apparatus as claimed in claim 20, wherein the means for providing an extended predetermined period between treatments comprises a smart card reader for reading an extended time period from a smart card.

22. Method of applying electronic treatment to a human being using an electronic treatment apparatus, the method comprising disabling the treatment apparatus for a predetermined time after a treatment is applied.