Patent No. 5877627 Device for detecting secondary magnetic fields induced in an organism by pusled magnetic fields

 

Patent No. 5877627

Device for detecting secondary magnetic fields induced in an organism by pusled magnetic fields (Fischer, et al., Mar 2, 1999)

Abstract

A device for determining the effect of pulsed primary magnetic fields on an organism has a measuring pick-up for secondary magnetic field signals generated by the organism in response to the primary magnetic fields. An evaluation circuit for the secondary magnetic field signals is provided. The evaluation circuit has a first memory device with a memory unit. The evaluation circuit has a control device. The control device includes a device for processing sequential secondary magnetic field signals such that the sequential secondary magnetic field signals are combined to a cumulative signal in the memory unit. The cumulative signal is used as an output signal of the evaluation circuit.

Notes:

SUMMARY OF THE INVENTION

The device for determining the effect of pulsed primary magnetic fields on an organism according to the present invention is primarily characterized by:

a measuring pick-up for secondary magnetic field signals generated by the organism in response to the primary magnetic fields;

an evaluation circuit for the secondary magnetic field signals;

the evaluation circuit comprising a first memory device with a memory unit;

the evaluation circuit further comprising a control device;

the control device comprising a means for processing sequential secondary magnetic field signals such that the sequential secondary magnetic field signals are combined to a cumulative signal in the memory unit; and

wherein the cumulative signal is used as an output signal of the evaluation circuit.

The measuring pick-up is preferably a measuring coil.

The evaluation circuit has a suppression circuit connected between the measuring pick-up and the memory unit, the suppression circuit comprising a control unit for allowing processing of the sequential secondary magnetic field signals only in a periods of rest after the primary magnetic pulses.

Preferably, the control device is designed such that the cumulative signal is a mean value of the sequential secondary magnetic field signals.

Expediently, the control device comprises a correlator for calculating the mean value, wherein the correlator performs an algebraic addition for the sequential secondary magnetic field signals and a geometric addition for disruptive signals.

The evaluation circuit, the memory unit and the control device are designed such that an amplitude of the sequential secondary magnetic field signals is determined.

Advantageously, the evaluation circuit, the memory unit and the control device are designed such that an energy contents of the sequential secondary magnetic field signals is determined.

The evaluation circuit, the memory unit and the control device are designed such that differential signals are calculated from the sequential secondary magnetic field signals and the differential signals are saved.

The device preferably further comprises a second memory device for saving the cumulative signals.

The evaluation circuit and the control device are designed such that, at the beginning of subjecting the organism with the pulsed primary magnetic fields, the cumulative signals are sent to the second memory device.

The evaluation circuit and the control device are designed such that, at the end of subjecting the organism with the pulsed primary magnetic fields, the cumulative signals are sent to the second memory device.

The evaluation circuit and the control device are designed such that, at the beginning and the end of subjecting the organism with the pulsed primary magnetic fields, the cumulative signals are sent to the second memory device.

The second memory device is preferably detachable from the device, and, in a preferred embodiment, is a chip card.

The second memory device comprises a plurality of sectors, wherein a first one of the sectors saves the cumulative signals as measured values, a second sector saves treatment parameters, and a third sector saves personal data of the organism.

The device may also further comprise a circuit for deriving a trigger signal from movements of the organism in order to ensure comparability of the sequential secondary magnetic field signals, wherein the evaluation circuit has a trigger element and wherein the trigger signal is sent to the trigger element so that the evaluation circuit is operational only at specific times determined by the trigger signal.

For ensuring comparability of the sequential secondary magnetic field signals, the measuring coil comprises means for securely attaching the measuring coil to the organism.

The device also further comprises an auxiliary coil for ensuring comparability of the sequential secondary magnetic field signals, wherein the second measuring coil is positioned remote from the measuring coil such that the auxiliary coil is exposed only to disruptive fields that also penetrate the measuring coil and wherein the measuring coil and the auxiliary coil are connected to an input of the evaluation circuit such that output signals of the measuring coil and the auxiliary coil are sent via an electric differential circuit to the input.

The measuring coil comprises a means for shielding against exterior magnetic disruptive fields in order to increase the signal-to-noise ratio of the evaluation circuit.

The device may further comprise an auxiliary chemical (electrochemical) gas measuring device for detecting gases emanating from the organism.

The device also may comprise a breathing mask, wherein the gas measuring device is integrated into the breathing mask.

The breathing mask comprises three connectors, wherein a first one of the connectors supplies compressed breathing air, a second one of the connectors receives the gas measuring device, and a third one of the connectors receives a controller for ensuring a substantially constant pressure for gas flow form a gas inlet of the measuring device to the exterior of the breathing mask.

The gas measuring device is a sensor for detecting at least one gas selected from the group consisting of HCl and NO.

The device preferably further comprises an auxiliary chemical (electrochemical) measuring device for detecting organism-specific fluids.

The device may also include a radiation thermometer for detecting the temperature of the organism, wherein the thermometer has an output and provides the measured temperature value as an electric signal at the output.

The radiation thermometer is designed to measure the temperature of the organism in one the bodily orifices. Preferably, the radiation thermometer measures the temperature of the organism in the ear of the organism.

The device may also include a device for applying the pulsed magnetic fields to the organism.

A blocking device for allowing activation of the device only when the second memory device is operational may be provided.

The device may also further comprise a blocking device for allowing activation of the device only during late morning hours and late afternoon hours.

In a device for determining the effect of pulsed primary magnetic fields on an organism, in which an evaluation circuit is provided for the signals derived from the organism by means of a measurement (measuring) pick-up designed, in a preferred embodiment, as a measurement (measuring) coil for secondary field signals (secondary magnetic field signals), this is achieved in accordance with the present invention due to the facts that the evaluation circuit has a storage (memory) device, that the storage device has a storage medium (memory unit) to which a control device is allocated, which is designed in such a way that several consecutive individual secondary magnetic field signals are written into the storage medium so that they are combined into a cumulative signal in the storage medium, and that this cumulative signal consisting of several individual signals is the output signal of the evaluation circuit.

There are several advantageous evaluation methods available for determining the effect. For example, it is possible to determine the amplitude value of secondary field signals and/or the energy content of secondary field signals in the evaluation circuit. An advantageous form of this design is to allocate to the evaluation circuit a circuit for determining the average (mean) value of several individual values. In a preferred embodiment, this allocated circuit takes the form of a correlator which performs algebraic addition on the individual values and geometric addition on the disruptive signals. In this manner, it is possible to raise the signal-to-noise ratio considerably, thereby increasing the accuracy of the information conveyed in the measurement results.

The embodiment in accordance with the present invention also makes it possible to create the evaluation circuit in such a manner that it feeds to the storage medium the value occurring at the beginning and/or the end of each occasion when the organism is subjected to pulsed magnetic fields. In accordance with a further advantageous embodiment, the evaluation circuit is designed so as to produce differential signals from the secondary field signals and store (save) them.

In an advantageous embodiment, the storage medium used is a memory device which can be separated from the device, and which may also be an additional storage medium (money device), in particular a memory chip card. It is also possible to divide the storage medium into several areas, one of which is used for storing measured values which have been determined, another of which is used for storing treatment data (parameters), and another is intended as a storage medium area with restricted access for storing personal data related to the organism.

The secondary magnetic fields are very weak, and so it is to be recommended that precautions be taken to ensure that the individual signals can be evaluated in a comparable manner in the storage medium. Such comparability is directly proportional,to the quality of the signal-to-noise ratio. An advantageous solution for this consists, for example, in having an auxiliary coil conelated with the measurement coil used for picking up the secondary signal from the organism, whereby this other coil is located away from the measurement coil so that it is only principally affected by the disruptive magnetic fields which also affect the measurement coil, and so that both coils are connected to the evaluation circuit input using an electrical differential circuit with respect to their output signals which are derived from the disruptive fields. For example, the other coil can be positioned at a certain distance above the measurement coil, so that it only principally picks up the spatial disruptive signals but to all intents and purposes does not pick up any secondary signal, whereas the measurement coil not only picks up the spatial disruptive signal, but also the secondary signal. Provided that the dimensions and number of windings of both coils are arranged so that they produce output signals which are at least approximately identical from the spatial interference, the coils can be linked together in an inverse electrical connection and connected to the evaluation circuit input. This results in a considerably improved signal being fed to the storage medium for further processing. It is also possible to harmonise the signals received from both coils with regard to the spatial interference using damping elements or control amplifiers, which, in a preferred embodiment, are adjustable. In order to improve the signal-to-noise ratio in the evaluation circuit, it is also possible to provide the measurement coil with a magnetic shield to protect it from external disruptive magnetic fields (magnetic spatial interference).

In this connection, means by which to remove the influence of changes in distance between the measurement pick-ups and the organism during the measurement process, in particular changes due to breathing movements, are advantageous. One possibility of doing so involves fixedly connecting the measurement pick-up to the organism. Another possibility which can be used additionally if need be consists of a circuit which derives a trigger signal in response to the movements of the organism, and to provide the evaluation circuit with a trigger element to which the trigger signal is sent, whereby the evaluation circuit is only operational at specific times as determined by the trigger signal, at which times the distance between the measurement pick-up, for example the measurement coil, and the relevant part of the organism is the same. This derivation circuit can take the form of, for example, a photoelectric barrier.

In a further embodiment of the present invention, and in particular as an additional feature, an electrochemical recording device or sensor is provided as a measurement pick-up for gases evolved by the organism or for liquids specific to the organism. In the case of a measurement pick-up (gas measuring device) for gases, this is incorporated to best advantage within a breathing mask. In a beneficial configuration, this measurement pick-up is a sensor device for hydrogen chloride (HCl) and/or nitrogen monoxide (NO).

In another further embodiment of the present invention, and in particular as an additional feature, a radiation thermometer is provided as a measurement pick-up for the temperature of the organism, whereby the radiation thermometer gives the temperature value as an electrical signal at its output. It has proven to be an advantage to produce the radiation thermometer as a measurement organ for measuring the temperature of the organism in one of its bodily openings, in particular in the ear of the organism. It is beneficial if the device is designed in such a way that it forms a single device unit together with a device for subjecting an organism to pulsating magnetic fields.

Furthermore, it is beneficial if a blocking device is provided in a device whose evaluation circuit is connected to an additional storage medium, in particular a removable storage medium, whereby the blocking device only permits activation of the device when the additional storage medium is switched on.

It has proven to be advantageous if a blocking device is provided in the device which only permits the device to be activated during the late morning and/or late afternoon.

A device and a process of prior art for measuring weak magnetic fields which are dependent on location and time is familiar from U.S. Pat. No. 5,152,288, in which a number of measurement pick-ups, there referred to as "superconducting quantum interference devices (SQUIDS)" pick-up the weak magnetic fields given off by the organism to be studied. Amongst other objects, SQUIDS are described with respect to their design, method of operation and application in a book entitled "Mikroelektronische Sensoren" by Waldmann and Ahlers, VEB Verlag Technik/Berlin, 1st edition 1989, pages 148/149, with bibliographical references. As shown in FIG. 7 of the printed patent specification referred to above, the signals picked up using SQUIDS are fed to, amongst other things, a storage medium, from where the stored values can be used further to derive an anatomical image of the object under investigation or to derive a model of the object under investigation. In accordance with this description, and as demonstrated by further descriptions in the printed patent specification, this is a device for tomography and is not a device for determining the effect of pulsed primary magnetic fields on an organism, and furthermore this device does not include a significant feature of the present invention, namely the storage medium with its particular control device.

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The present invention is, of course, in no way restricted to the specific disclosure of the specification and drawings, but also encompasses any modifications within the scope of the appended claims.