JPH1147106A - Electrode for measuring biological signal and electrode aid for measuring biological signal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce noises generated in lead wires connected to the electrodes of an electroencephalograph or electrocardiograph, when they are used inside a strong magnetic field. SOLUTION: An electrode for measuring biological signals includes thin-foil electrodes 11a-11c each formed in the shape of a trapezoid, lead wires 12a-12c connected to the respective electrodes 11a-11c, and support 13 formed in the shape of a slender, thin plate made of a flexible material such as rubber or plastics and supporting the electrodes 11a-11c in a straight line at certain intervals, the lead wires 12a-12c being twisted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrode for measuring a biological signal and an electrode assisting device for measuring a biological signal suitable for use in a medical measuring device for measuring biological information such as an electroencephalograph and an electrocardiograph.

[0002]

2. Description of the Related Art Conventionally, MRI (Magnetic Resonance Ins.
In the diagnosis of trument), EEG and ECG are measured. FIG. 10 is a diagram showing a schematic configuration of the MRI. When taking an electroencephalogram or electrocardiogram in the diagnosis of MRI, M
Under the strong magnetic field formed in the RI gantry, the motion of the subject's body causes voltage due to Faraday's law to appear on the lead wires of the electrodes of the electroencephalograph and the electrocardiograph, resulting in noise, making it impossible to measure accurately. ing. Since this problem is also caused by minute body movements caused by the heartbeat of the subject, urgent measures are awaited. FIG. 11 shows waveforms of an electrocardiogram and noise. It can be seen that noise appears in synchronization with the electrocardiogram. The level of this noise varies depending on the electrode mounting portion and the way in which the lead wire is drawn from the electrode mounting portion, and is proportional to the number of magnetic fluxes interlinked.

[0003]

Conventionally, to solve this problem, the arrangement direction of the lead wires of the electrodes is adjusted to the direction of the magnetic field lines so that the opening area with respect to the magnetic field lines is reduced, or a filter is used in a signal processing circuit. Although it is provided,
This alone was not enough to suppress noise. Therefore, the present invention provides a biosignal measurement electrode and a biosignal measurement electrode auxiliary tool that can suppress noise generated in a lead wire connected to an electrode of an electroencephalograph or an electrocardiograph when used in a magnetic field. It is intended to provide.

[0004]

In order to achieve the above-mentioned object, according to the present invention, the electrode for measuring a biological signal according to the present invention is connected to a plurality of electrodes for extracting a biological signal and to each of these electrodes. A lead signal, an electrode for measuring a biological signal comprising a support member having flexibility and insulating properties such as plastic and rubber, respectively supporting the plurality of electrodes and the lead wires, wherein the plurality of lead wires are , Are tightly twisted in the support member and are arranged in a straight line. According to this configuration, since the lead wires connected to the respective electrodes are tightly twisted in the support member, they have almost no opening area with respect to the magnetic force lines even when placed in a magnetic field. Even when used with an apparatus that forms a magnetic field, the voltage induced on each lead wire is small, and an accurate measurement of an electrocardiogram or an electroencephalogram can be performed.

According to a second aspect of the present invention, there is provided an electrode for measuring a biological signal, comprising: a plurality of electrodes for extracting a biological signal; a plurality of leads connected to each of the electrodes;
While having flexibility and insulating properties such as plastic and rubber, each of the plurality of electrodes is stacked so as not to overlap each other, and each of the plurality of lead wires is stacked so as to overlap each other in a non-contact state. And a supporting member to be made. According to this configuration, each of the plurality of electrodes is stacked so as not to overlap each other, and each of the plurality of lead wires is stacked so as to overlap each other in a non-contact state. Thus, even when used with an apparatus for forming a strong magnetic field such as MRI, the voltage induced in each lead wire is small, and an accurate measurement of an electrocardiogram or an electroencephalogram becomes possible.

It is to be noted that the support member may further be provided with a sensor for generating a voltage corresponding to the number of magnetic fluxes interlinked when placed in a magnetic field. In this sensor, for example, a conductive wire is arranged in a loop shape with a predetermined width in a support member.

According to a fifth aspect of the present invention, there is provided an electrode assisting device for measuring a biological signal, which is made of plastic, rubber, or the like, has flexibility and insulating properties, and accommodates a plurality of electrodes for extracting a biological signal. And a groove portion for linearly leading each of the lead wires connected to each electrode to the outside. According to this structure, each lead wire can be fixed in a straight line, so that the opening area in the stacking direction with respect to the magnetic force lines can be reduced, thereby inducing each lead wire even when used together with a device for forming a strong magnetic field such as MRI. The voltage is very low, which enables accurate measurement of electrocardiograms and brain waves. It should be noted that a housing for housing a sensor that generates a voltage corresponding to the number of magnetic fluxes interlinked may be provided in the electrode assisting device for measuring a biological signal.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of a biological signal measuring electrode and a biological signal measuring electrode assisting tool according to the present invention. (I) First Embodiment of Biosignal Measurement Electrode FIG. 1 is a first embodiment of a biosignal measurement electrode according to the present invention.
2 is a perspective view seen from above, and FIG.
It is the perspective view seen from. The biological signal measurement electrode 10 of the first embodiment is a thin foil electrode 11a formed in a square shape.
To 11c, lead wires 12a to 12c connected to each of the electrodes 11a to 11c, and a thin and long plate made of a flexible material such as rubber or plastic, and the electrodes 11a to 11c are fixed in a straight line. Support part 1 to support at intervals
3 is provided.

The electrodes 11a and 11c are electrodes for extracting biological signals, one of which is a positive electrode (+) and the other is a negative electrode (-). The electrode 11b is a reference electrode (E). The lead wires 12a to 12c are tightly twisted with each other so as not to have an opening area with respect to the magnetic force lines. Support part 13
Are two plate-like members 13a, 13a as shown in the sectional view of FIG.
b, which are bonded together with an adhesive. An extremely fine groove 15 (see FIG. 1) for passing the lead wires 12a to 12c is formed in the plate-like body 13a in the longitudinal direction, and the lead wires 12a to 12c are inserted into the groove 15 in a twisted state. ing. In addition, lead wires 12a-1
An insulating coating is formed on 2c, and no short circuit occurs even when twisted with each other. The portions of the lead wires 12a to 12c protruding from the support portion 13 are also tightly twisted with each other so that the opening area with respect to the lines of magnetic force is reduced.

[0010] The biological signal measuring electrode 10 is configured as described above, and since the lead wires 12a to 12c connected to the respective electrodes 11a to 11c are closely twisted with each other,
It has almost no opening area for the magnetic field lines, and this
Even when used with an apparatus for forming a strong magnetic field such as I, only a small voltage is generated on these lead wires 12a to 12c, and almost no noise is generated.

(II) Second Embodiment of Biosignal Measurement Electrode FIG. 3 shows a second embodiment of a biosignal measurement electrode according to the present invention.
FIG. 4 is a perspective view as viewed from above, and FIG.
It is the perspective view seen from.

In this case, as shown in FIG. 3 and FIG. 4, the electrodes 11a to 11c are arranged so as to be shifted from each other so as to be at a constant interval in a straight line. Also, the lead wires 22a to 22a
c are arranged so as to overlap each other in the thickness direction of the electrode body. By disposing the lead wires 22a to 22c so as to overlap each other in the thickness direction of the electrode main body and molding and fixing them with rubber or plastic, displacement can be prevented and the vertical opening area with respect to the magnetic force lines can be reduced. For the opening area in the width direction, the lead wires 22a to 22
By making each of c thin, the size can be reduced.

As described above, the biological signal measuring electrode 20 according to the second embodiment is arranged such that the lead wires 22a to 22c overlap each other in the thickness direction of the electrode body, so that the thickness of the lead wires 22a to 22c with respect to the magnetic force lines is reduced. The opening area in the direction is small, so that even when used with an apparatus for forming a strong magnetic field such as MRI, only a small voltage is generated in the lead wires 22a to 22c, and almost no noise is generated. In addition,
When the electrodes 11a to 11c and the lead wires 22a to 22c are formed by a flexible printed board or the like, the opening area in the thickness direction can be made smaller and the whole can be made thinner.

(III) Third Embodiment of Biosignal Measurement Electrode FIG. 5 shows a third embodiment of a biosignal measurement electrode according to the present invention.
FIG. 4 is a perspective view showing a view from above. The electrode 30 for measuring a biological signal according to the third embodiment is connected to the lead wire 12a in a strong magnetic field.
1 to 12c is provided with a noise detection sensor 31 for detecting a current flowing through .about.12c. The sensor 31 has a conductive wire formed in a loop shape with a predetermined width in the support portion 13, and is inserted into a groove 32 formed along the periphery of the electrodes 11 a to 11 c of the plate-like body 13 a of the support portion 13. I have. By forming the lead wire into a loop and having an opening area for the magnetic force lines, a voltage large enough to detect noise is generated, and the noise can be detected reliably.

FIG. 6 is a block diagram showing a configuration of a signal processing circuit using the biological signal measuring electrode 30. As shown in FIG. In this figure, the biological signal obtained by the electrodes 11a to 11c is amplified by the amplifier 40, while the signal obtained by the sensor 31 is amplified by the amplifier 41. The output of the amplifier 40 is supplied to a non-inverting input terminal of a comparator 42, and the output of the amplifier 41 is supplied to an inverting input terminal of the comparator 42 via an attenuator 43. An output corresponding to the difference between the output of the amplifier 40 and the output of the amplifier 41 is obtained from the comparator 42, and this output is supplied to a measurement circuit (not shown) and to a noise detection unit 44. The noise detection unit 44 detects a noise component from the output of the comparator 42 and adjusts the attenuation rate of the attenuator 43 so that the value becomes zero.

(IV) Embodiment of Biological Signal Measuring Electrode Auxiliary Tool FIG. 7 is a perspective view showing an embodiment of a biological signal measuring electrode auxiliary tool according to the present invention, and FIG. 8 is a plan view showing a part thereof. It is. The biological signal measurement electrode assisting device (hereinafter, referred to as an electrode assisting device) 50 of this embodiment includes two rectangular portions (hereinafter, referred to as a plate-like body) 50a formed of a flexible material such as rubber or plastic. , 50b, of which the plate-shaped body 50b has a receiving portion 53a for receiving electrodes 60a to 60c (see FIG. 8) for extracting a biological signal.
To 53c, and elongated grooves 54 for accommodating lead wires 61a to 61c connected to the respective electrodes 60a to 60c. The electrodes 60a to 60c are conventionally used independently.

As shown in the plan view of FIG. 8, the groove 54 is formed in the same direction as the arrangement direction of the housing portions 53a to 53c and adjacent to the housing portions 53a to 53c. Plate 50
As shown in the perspective view of FIG. 7, a and 50b are hingedly connected at one end in the longitudinal direction, and are openable and closable. In order to prevent the plate-shaped members 50a and 50b from being easily opened when closed, a locking piece 5 is provided at the central portion of each opening side end.
1, 52 are formed. As shown in the cross-sectional view of FIG. 9, a concave portion is formed in the central portion inside the locking piece 51, and the locking piece 52 fits into this concave portion. By fitting the locking pieces 52 into the recesses of the locking pieces 51, the plate-like bodies 50a and 50b can be reliably closed.

The electrode assisting device 50 is configured as described above, and when used, the plate-like members 50a and 50b are opened to open the plate-like member 5a.
The electrodes 60a to 60c are put into the accommodating portions 53a to 53c of Ob, and then the lead wires 61a to 61c are put into the groove 54. At this time, the lead wires 61a to 61c are twisted. Electrodes 60a-60c and lead wires 61a-61
After inserting c, the plate-like bodies 50a and 50b are closed. Since the lead wires 61a to 61c are housed in a state in which they are in close contact with each other, the lead wires 61a to 61c have almost no opening area for the magnetic force lines. Also lead wire 6
Only a small voltage is generated in 1a to 61c, and almost no noise is generated.

The electrode assisting tool 50 may be provided with a groove for accommodating the noise detecting sensor 31 described above. Also, the shape is not limited to this embodiment,
Electrodes 60a to 60c can be accommodated and lead wire 61a
To 61c may be any shape as long as it can accommodate linearly.

[0020]

According to the biological signal measuring electrode of the present invention, the lead wires connected to each of the plurality of electrodes are densely twisted so that the opening area with respect to the magnetic force lines is minimized. Even if placed in such a strong magnetic field, noise is hardly generated, and accurate measurement results can be obtained in electrocardiograms and brain waves.

According to the second aspect of the present invention, the lead wires connected to each of the plurality of electrodes are arranged so as to overlap each other in the thickness direction of the electrode body so that the opening area with respect to the lines of magnetic force is minimized. Therefore, even when the device is placed in a strong magnetic field such as an MRI, almost no noise is generated, and accurate measurement results can be obtained in electrocardiograms and brain waves.

According to the third aspect of the present invention, since the sensor for detecting a voltage corresponding to the number of interlinking magnetic fluxes is provided, an electrocardiogram is obtained when the biosignal measuring electrode is placed in a magnetic field. Can be picked up, and can be used for canceling out slight noise contained in the biological signal obtained from the biological signal measuring electrode.

According to the biological signal measuring electrode assisting device of the fifth and sixth aspects, the lead wires connected to the respective electrodes can be fixed in a straight line, so that the opening area in the stacking direction with respect to the magnetic force lines can be reduced, thereby reducing the MRI. Even when used with an apparatus that forms such a strong magnetic field, it is possible to suppress the generation of noise due to the current generated in each lead wire. In addition, by providing a sensor that detects a voltage corresponding to the number of interlinking magnetic fluxes, when this biosignal measurement electrode is placed in a magnetic field, noise synchronized with the electrocardiogram can be picked up. It can be used for canceling slight noise contained in the obtained biological signal.

[Brief description of the drawings]

FIG. 1 is a perspective view of a biological signal measuring electrode according to a first embodiment of the present invention, as viewed from above.

FIG. 2 is a perspective view seen from an arrow A in FIG.

FIG. 3 is a perspective view, viewed from above, of a biological signal measurement electrode according to a second embodiment of the present invention.

FIG. 4 is a perspective view as viewed from an arrow B in FIG. 3;

FIG. 5 is a perspective view of a biological signal measuring electrode according to a third embodiment of the present invention, as viewed from above.

FIG. 6 is a block diagram illustrating a configuration of a signal processing circuit using the biological signal measurement electrode according to the third embodiment.

FIG. 7 is a perspective view showing an embodiment of the electrode assisting device for measuring a biological signal according to the present invention.

FIG. 8 is a plan view of a part of the embodiment of the electrode assisting device for measuring a biological signal.

FIG. 9 is a cross-sectional view of a part of the embodiment of the electrode assisting device for measuring a biological signal.

FIG. 10 is a schematic configuration diagram of MRI.

FIG. 11 is a waveform diagram showing an electrocardiogram and a current generated in a lead wire.

[Explanation of symbols]

10, 20, 30 Biological signal measurement electrodes 11a to 11c, 60a to 60c Electrodes 12a to 12c, 22a to 22c Lead wire 13 Supports 13a, 13b, 21a to 21d, 50a, 50b Plate 15, 32, 54 Grooves Reference Signs List 31 sensor 50 biological signal measurement electrode auxiliary tool 51, 52 locking pieces 53a to 53c accommodation portion

Claims (6)

[Claims] 1. A plurality of electrodes for extracting a biological signal, a lead wire connected to each of these electrodes, and a flexible and insulating material such as plastic, rubber or the like that supports the plurality of electrodes and the lead wire, respectively. A biosignal measurement electrode comprising: a biosignal measurement electrode comprising: a plurality of lead wires that are closely twisted and arranged in a straight line in the support member. Electrodes. 2. A plurality of electrodes for extracting a biological signal, a plurality of lead wires connected to each of the electrodes, and a flexible and insulating material such as plastic or rubber. A supporting member for arranging each of the plurality of lead wires so as to overlap each other in a non-contact state while arranging each of the plurality of lead wires so as not to overlap with each other; 3. The sensor according to claim 1, further comprising a sensor supported by the support member and configured to generate a current corresponding to the number of magnetic fluxes interlinked when the sensor is placed in a magnetic field. For measuring biological signals. 4. The electrode for measuring a biological signal according to claim 3, wherein the sensor has a conductive wire arranged in a loop with a predetermined width in a support member. 5. A plurality of storage sections, each of which has flexibility and insulation properties such as plastic and rubber, and stores each of a plurality of electrodes for extracting a biological signal, and a lead wire connected to each electrode. And a groove for pulling out the electrode in a straight line to the outside. 6. An electrode assisting device for measuring a biological signal according to claim 5, further comprising a housing for housing a sensor for generating a current corresponding to the number of magnetic fluxes linked by being placed in a magnetic field. .