An overlapping stimulation coil assembly and system for bioelectromagnetic stimulation

Abstract

The present invention discloses an overlapping stimulation coil assembly and system for bioelectromagnetic stimulation, which relates to the field of bioelectromagnetic stimulation technology. The assembly includes a lower stimulation coil and an upper stimulation coil for vertical placement above a bioelectromagnetic stimulation target area, wherein the upper and lower stimulation coils have the same and similar geometric structure of a semicircular coil structure, the upper and lower stimulation coils are arranged overlappingly, and the arc portion of the lower stimulation coil, the arc portion of the upper stimulation coil, the straight long axis portion of the lower stimulation coil, and the straight long axis portion of the upper stimulation coil are arranged in sequence from bottom to top, and the upper and lower stimulation coils are used to respectively access excitation currents through different discharge circuits to jointly exert bioelectromagnetic stimulation on the target area. In this way, while ensuring that the stimulation intensity reaches the stimulation threshold, the focusing of the stimulation coil is improved, the stimulation depth within the skull is enhanced, the adverse effects on non-target areas are effectively reduced, and the safety of transcranial electromagnetic stimulation treatment is ensured.

Description

Technical Field

[0001] The present invention belongs to the technical field of bioelectromagnetic stimulation, and in particular relates to an overlapping stimulation coil assembly and system for bioelectromagnetic stimulation. Background Art

[0002] Bio / transcranial electromagnetic stimulation (BEM) technology emerged from interdisciplinary fields, encompassing medicine, neuroelectrophysiology, and electromagnetics. It has made significant contributions to the treatment of neurological diseases and the exploration of brain structure and function. To achieve precise and effective stimulation of intracranial target areas while minimizing side effects, the geometric design optimization of the stimulation coil has always been a focus.

[0003] The fundamental physical principle of transcranial electromagnetic stimulation (TES) is Faraday induction, which involves passing a rapidly varying excitation current through a stimulation coil. This time-varying current generates a time-varying magnetic field, which in turn induces currents in brain tissue. This induced current then generates an induced electric field, stimulating neural tissue within the brain, causing hyperpolarization or depolarization of neuronal membrane potentials, resulting in a series of physiological changes. The therapeutic effectiveness of TES depends on numerous parameters, such as stimulation time, intensity, duration, and the type of stimulation current. Currently, there are still issues such as poor focus, insufficient stimulation depth, and limited pulse width and frequency adjustment. Furthermore, application safety is a key research priority.

[0004] The focusing of the induced electric field of the stimulation coil is a key parameter in transcranial electromagnetic stimulation technology. By designing and optimizing the coil geometry, material selection, and spatial arrangement, studying the distribution of the magnetic field and induced electric field, and determining the stimulation range, the precision of stimulation of the target area can be effectively improved, the impact on surrounding non-target areas can be reduced, and the risk of inducing symptoms can be reduced. Currently, most research on stimulation coils is based on the design of a figure-eight coil to improve the focusing of the induced electric field. Transcranial electromagnetic stimulation generates a strong magnetic field through a strong current passing through the coil, and uses magnetic field gradient control and focusing positioning technology for stimulation. However, due to the complexity of magnetic field gradient control and positioning control, low-frequency stimulation is used to avoid overheating of the coil due to high-frequency stimulation. Therefore, flexible control of multiple stimulation parameters is important in application.

[0005] The magnetic stimulation coil is an important carrier for realizing transcranial magnetic stimulation and converting time-varying current into specific magnetic fields and induced electric fields. It is the core of the entire transcranial electromagnetic stimulation and also the difficulty of design. It determines the stimulation intensity, stimulation depth and focus of the magnetic stimulation. By improving the stimulation focus of the target area and reducing the stimulation of non-target areas, the occurrence of complications can be reduced. The size, shape, and material of the coil, the waveform, intensity, and frequency of the stimulation current in the coil, and its placement, direction, and angle will all affect the stimulation effect. Specifically, it can affect the distribution shape, focus, stimulation depth, stimulation position, equipment energy utilization, and safety of the induced electric field. Therefore, the design and research of the coil is the key to this technology. At present, the performance of the stimulation coil is mainly improved from multiple aspects such as coil shape structure, coil array design, and adding auxiliary materials such as shielding plates.

[0006] In summary, how to provide a new stimulation coil that can induce a more concentrated induced electric field, improve focus, and have more balanced stimulation performance, so as to minimize the impact on non-target tissues while effectively stimulating the target point and ensure the effectiveness and safety of transcranial electromagnetic stimulation treatment, is a topic that technicians in this field urgently need to study. Summary of the Invention

[0007] The purpose of the present invention is to provide an overlapping stimulation coil assembly and a coil overlapping stimulation system for bioelectromagnetic stimulation, so as to solve the problem that traditional stimulation coils have characteristics such as stimulation depth and focusing that cannot be taken into account at the same time. In addition, while ensuring that the stimulation intensity reaches the stimulation threshold, the focusing of the stimulation coil can be improved, the stimulation depth in the skull can be enhanced, and the adverse effects on non-target areas can be effectively reduced, thereby ensuring the safety of transcranial electromagnetic stimulation treatment.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] In a first aspect, an overlapping stimulation coil assembly for bioelectromagnetic stimulation is provided, comprising a lower stimulation coil and an upper stimulation coil for vertical placement above a target area of bioelectromagnetic stimulation, wherein the lower stimulation coil and the upper stimulation coil have the same geometric structure similar to a semicircular coil structure;

[0010] The lower stimulation coil and the upper stimulation coil are arranged in an overlapping manner, and the arc portion of the lower stimulation coil, the arc portion of the upper stimulation coil, the straight long axis portion of the lower stimulation coil and the straight long axis portion of the upper stimulation coil are arranged in sequence from bottom to top;

[0011] The lower stimulation coil and the upper stimulation coil are used to respectively access the excitation current through different discharge circuits to jointly exert a bioelectromagnetic stimulation effect on the bioelectromagnetic stimulation target area.

[0012] Based on the above invention, a new stimulation coil design scheme is provided which can induce a more concentrated induced electric field, improve focusing and have a more balanced stimulation performance, namely, a lower stimulation coil and an upper stimulation coil for vertically placing above the target area of biological electromagnetic stimulation, wherein the upper and lower stimulation coils have the same and similar geometric structure of the semicircular coil structure, the upper and lower stimulation coils are arranged in an overlapping manner, and the arc portion of the lower stimulation coil, the arc portion of the upper stimulation coil, the straight long axis portion of the lower stimulation coil and the straight long axis portion of the upper stimulation coil are arranged in sequence from bottom to top, and the upper and lower stimulation coils are arranged in an overlapping manner. The excitation coils are used to access the excitation current through different discharge circuits to jointly exert bioelectromagnetic stimulation on the target area. In this way, the mutual influence and superposition of the electromagnetic fields generated by the excitation currents of the upper and lower stimulation coils can produce a strong and focused stimulation effect in the target area, effectively suppressing the negative peak of the coil's induced electric field, and at the same time enhancing the aggregation of the induced electric field. As a result, while ensuring that the stimulation intensity reaches the stimulation threshold, the focusing of the stimulation coil can be improved, the stimulation depth in the skull can be enhanced, and the adverse effects on non-target areas can be effectively reduced, thereby ensuring the safety of transcranial electromagnetic stimulation treatment and facilitating practical application and promotion.

[0013] In one possible design, the lower stimulation coil or the upper stimulation coil adopts a multi-layer multi-turn coil structure, and the excitation current flows into the lead-in end of the outer straight long axis segment of the multi-layer multi-turn coil structure, and then flows out from the lead-out end of the inner circular arc segment of the multi-layer multi-turn coil structure.

[0014] In a possible design, the lower stimulation coil and the upper stimulation coil are further used to adjust the stimulation intensity and stimulation focus of the bioelectromagnetic stimulation target area through different overlapping angles and / or coil widths.

[0015] In a possible design, the lower stimulation coil and the upper stimulation coil are further used to adjust the degree of directional deviation of the bio-electromagnetic stimulation target area through excitation currents of different magnitudes.

[0016] In a possible design, it further includes an annular shielding plate for wrapping the lower stimulation coil and the upper stimulation coil and having an opening at the bottom.

[0017] In a possible design, the annular shielding plate is formed by stacking thin silicon steel sheets.

[0018] In a second aspect, a coil overlapping stimulation system is provided, comprising a control module, a first charging power module, a second charging power module, a first energy storage capacitor, a second energy storage capacitor, a first discharge switch, a second discharge switch, a first discharge circuit, a second discharge circuit, and the overlapping stimulation coil assembly for bioelectromagnetic stimulation as described in the first aspect, wherein the output end of the control module is electrically connected to the controlled ends of the first charging power module, the second charging power module, the first discharge switch, and the second discharge switch, respectively;

[0019] The positive output terminal of the first charging power module is electrically connected to one end of the first energy storage capacitor and one end of the first discharge switch, respectively; the other end of the first discharge switch is electrically connected to the positive input terminal of the first discharge circuit; the negative output terminal of the first charging power module is electrically connected to the other end of the first energy storage capacitor and the negative input terminal of the first discharge circuit, respectively; the positive output terminal of the first discharge circuit is electrically connected to the excitation current introduction terminal of the lower stimulation coil in the overlapping stimulation coil assembly, and the negative output terminal of the first discharge circuit is electrically connected to the excitation current lead-out terminal of the lower stimulation coil;

[0020] The positive output terminal of the second charging power module is electrically connected to one end of the second energy storage capacitor and one end of the second discharge switch, respectively; the other end of the second discharge switch is electrically connected to the positive input terminal of the second discharge circuit; the negative output terminal of the second charging power module is electrically connected to the other end of the second energy storage capacitor and the negative input terminal of the second discharge circuit, respectively; the positive output terminal of the second discharge circuit is electrically connected to the excitation current introduction terminal of the upper stimulation coil in the overlapping stimulation coil assembly; and the negative output terminal of the second discharge circuit is electrically connected to the excitation current lead-out terminal of the upper stimulation coil;

[0021] The first charging power module is used to convert the alternating current into a first direct current and output it under the control of the control module;

[0022] The second charging power module is used to convert the AC power into a second DC power and output it under the control of the control module;

[0023] The control module is configured to control the first discharge switch to be turned on when the voltage across the first energy storage capacitor reaches a first expected value, so as to discharge the first energy storage capacitor through the first discharge circuit; and to control the second discharge switch to be turned on when the voltage across the second energy storage capacitor reaches a second expected value, so as to discharge the second energy storage capacitor through the second discharge circuit;

[0024] The first discharge circuit is configured to send a first excitation current to the lower stimulation coil when the first energy storage capacitor is discharged;

[0025] The second discharge circuit is used to send a second excitation current to the upper stimulation coil when the second energy storage capacitor is discharged.

[0026] In a possible design, a first clamping diode connected in parallel with the first energy storage capacitor and / or a second clamping diode connected in parallel with the second energy storage capacitor is further included.

[0027] In one possible design, an information acquisition module is further included that is communicatively connected to the control module, wherein the information acquisition module is used to acquire electrophysiological response information generated by the stimulation when the bio-electromagnetic stimulation target area is stimulated, and transmit the electrophysiological response information to the control module for information analysis.

[0028] In a possible design, the first discharge switch or the second discharge switch is a thyristor.

[0029] Beneficial effects of the above scheme:

[0030] (1) The present invention provides a novel stimulation coil design scheme that can induce a more concentrated induced electric field, improve focusing and have a more balanced stimulation performance, namely, a lower stimulation coil and an upper stimulation coil for vertically placing above the target area of biological electromagnetic stimulation, wherein the upper and lower stimulation coils have the same and similar geometric structure of the semicircular coil structure, the upper and lower stimulation coils are arranged in an overlapping manner, and the arc portion of the lower stimulation coil, the arc portion of the upper stimulation coil, the straight long axis portion of the lower stimulation coil and the straight long axis portion of the upper stimulation coil are arranged in sequence from bottom to top, and the upper and lower stimulation coils are arranged in a manner that is consistent with the above. The coils are used to connect to the excitation current through different discharge circuits to jointly exert bioelectromagnetic stimulation on the target area. In this way, the electromagnetic fields generated by the excitation currents of the upper and lower stimulation coils interact and overlap, which can produce a strong and focused stimulation effect in the target area, effectively suppressing the negative peak of the coil-induced electric field and enhancing the concentration of the induced electric field. This can improve the focusing of the stimulation coil while ensuring that the stimulation intensity reaches the stimulation threshold, enhance the stimulation depth within the skull, effectively reduce adverse effects on non-target areas, ensure the safety of transcranial electromagnetic stimulation treatment, and facilitate practical application and promotion.

[0031] (2) Compared with the limitation of traditional parallel placement of coils, the vertical placement of overlapping coils effectively increases the contact area with the air, which is beneficial to the heat dissipation of the coils during operation;

[0032] (3) Different stimulation combinations can achieve directional target deviation and focusing, while taking into account the improvement of focus depth and stimulation range, and reducing the impact on non-target areas;

[0033] (4) By adding an annular shielding plate made of thin silicon steel sheets on the outside, the eddy current loss inside the overlapping stimulation coil can be effectively reduced, the magnetic energy loss can be reduced, and the focusing effect of the coil can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0035] Figure 1 This is a schematic diagram of the arrangement relationship between the overlapping stimulation coil assembly for bio-electromagnetic stimulation provided in an embodiment of the present application and the human head, wherein: Figure 1 (a) shows a schematic diagram of the three-dimensional structure of the arrangement relationship, Figure 1 (b) in the figure shows a schematic diagram of the top view of the arrangement relationship.

[0036] Figure 2 A schematic diagram of the three-dimensional structure of the multi-layer and multi-turn coil structure in the overlapping stimulation coil assembly provided in an embodiment of the present application.

[0037] Figure 3 A side view schematic diagram of the multi-layer and multi-turn coil structure in the overlapping stimulation coil assembly provided in an embodiment of the present application.

[0038] Figure 4 Schematic diagram of the positional relationship between the annular shielding plate and the human head in the overlapping stimulation coil assembly provided in an embodiment of the present application, wherein: Figure 4 (a) shows a schematic diagram of the three-dimensional structure of the positional relationship, Figure 4 (b) shows a side view of the positional relationship. Figure 4 (c) in the figure shows a schematic diagram of the top view of the positional relationship.

[0039] Figure 5 This is a comparative example diagram of the stimulation effects produced by different coil widths and different overlap angles provided in the embodiment of the present application, wherein: Figure 5 (a) shows an example comparison of the stimulation intensity of the intracranial target area generated by different coil widths and different overlap angles. Figure 5 (b) shows an example comparison of the focal area of the intracranial target region generated based on different coil widths and different overlap angles.

[0040] Figure 6 This is an example diagram comparing the differences in electric field strengths generated by stimulation currents of different sizes provided in an embodiment of the present application.

[0041] Figure 7 This is a comparative example diagram of the induced electric field distribution generated by the overlapping stimulation coil assembly and the traditional coil provided in the embodiment of the present application, wherein: Figure 7 (a) shows a comparative example of the distribution of the induced electric field generated by the overlapping stimulation coil assembly and the traditional coil along the X test line. Figure 7 (b) shows an example comparison of the distribution of the induced electric field intensity in the target area generated by the overlapping stimulation coil assembly and the traditional coil in the Z direction within the skull.

[0042] Figure 8 This is a comparative example diagram of the induced electric field distribution generated by the overlapping stimulation coil assembly and the traditional coil in the intracranial target plane provided in the embodiment of the present application, wherein: Figure 8 (a) shows the three-dimensional structure of the traditional figure-eight coil and the human skull. Figure 8 (b) shows the distribution of the induced electric field generated by the traditional figure-eight coil on the target plane at a stimulation depth of 20 mm from the scalp vertex. Figure 8 (c) in FIG. 4 shows a three-dimensional structure diagram of the overlapping stimulation coil assembly and the human skull. Figure 8 (d) shows the distribution of the induced electric field generated by the overlapping stimulation coil assembly on the target plane at a stimulation depth of 20 mm from the scalp vertex.

[0043] Figure 9 This is a schematic diagram of the structure of the coil overlapping stimulation system provided in an embodiment of the present application, wherein: Figure 9 (a) shows a schematic diagram of the circuit connection relationship between the control module, the first charging power module, the first energy storage capacitor, the first discharge switch, the first discharge circuit and the overlapping stimulation coil assembly in the coil overlapping stimulation system. Figure 9 (b) shows a schematic diagram of the circuit connection relationship between the control module, the second charging power module, the second energy storage capacitor, the second discharge switch, the second discharge circuit and the overlapping stimulation coil assembly in the coil overlapping stimulation system. DETAILED DESCRIPTION

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the present invention will be briefly introduced below in conjunction with the drawings and the description of the embodiments or the prior art. Obviously, the following description of the structure of the drawings is only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention.

[0045] It should be understood that although the terms first, second, etc. may be used herein to describe various objects, these objects should not be limited by these terms. These terms are merely used to distinguish one object from another. For example, a first object can be referred to as a second object, and similarly, a second object can be referred to as a first object without departing from the scope of the exemplary embodiments of the present invention.

[0046] It should be understood that the term "and / or" that may appear in this document is merely a description of the association relationship between associated objects, indicating that there may be three relationships. For example, A and / or B can indicate three situations: A exists alone, B exists alone, or A and B exist at the same time. For another example, A, B and / or C can indicate the existence of any one of A, B and C or any combination of them. The term " / and" that may appear in this document describes another type of association object relationship, indicating that there may be two relationships. For example, A / and B can indicate two situations: A exists alone or A and B exist at the same time. In addition, the character " / " that may appear in this document generally indicates that the previous and next associated objects are in an "or" relationship.

[0047] Example:

[0048] like Figures 1 to 3 As shown, the overlapping stimulation coil assembly provided in the first aspect of this embodiment and used for bioelectromagnetic stimulation includes but is not limited to a lower stimulation coil 1 and an upper stimulation coil 2 for vertically placing above the bioelectromagnetic stimulation target area 100, wherein the lower stimulation coil 1 and the upper stimulation coil 2 have the same and similar geometric structure of a semicircular coil structure; the lower stimulation coil 1 and the upper stimulation coil 2 are arranged overlappingly, and the arc portion of the lower stimulation coil 1, the arc portion of the upper stimulation coil 2, the straight long axis portion of the lower stimulation coil 1 and the straight long axis portion of the upper stimulation coil 2 are arranged in sequence from bottom to top; the lower stimulation coil 1 and the upper stimulation coil 2 are used to respectively access the excitation current through different discharge circuits to jointly exert a bioelectromagnetic stimulation effect on the bioelectromagnetic stimulation target area 100.

[0049] like Figures 1 to 3 As shown, in the specific structure of the overlapping stimulation coil assembly, the lower stimulation coil 1 and the upper stimulation coil 2 respectively adopt a multi-layer multi-turn coil structure, and the excitation current flows into the lead-in end of the outer straight long axis segment of the multi-layer multi-turn coil structure, and then flows out from the lead-out end of the inner circular arc segment of the multi-layer multi-turn coil structure. The current direction of the excitation current is as shown in FIG. Figure 2As shown by the black solid arrow in the figure. According to the principle of electromagnetic field superposition, the electromagnetic fields generated by the excitation currents (specifically pulsed currents) of the upper and lower stimulation coils will influence and superimpose each other, thereby producing a strong and focused stimulation effect in the target area, effectively suppressing the negative peak of the coil-induced electric field and enhancing the aggregation of the induced electric field. In addition, the semicircular coil structure specifically includes but is not limited to a semicircular coil structure, a semi-elliptical coil structure, a U-shaped coil structure, and an inverted parabolic coil structure.

[0050] like Figure 2 As shown, the arc portion of the multi-layer multi-turn coil structure is placed vertically close to the human head 200, which will stimulate the intracranial target area (i.e., the bio-electromagnetic stimulation target area 100 can be, but is not limited to, for example, the area Figure 1 The distribution and formation of the induced electric field (as shown) play an important role: Figure 3 As shown in the figure, compared with coils of other shapes, arc-shaped coils have greater advantages in terms of safety and stimulation effect. The degree of curvature of this part will also affect the superposition effect of the intracranial induced electric field. Figure 3 The coil segment parallel to the X axis is the straight long axis segment, its length is Rx, and let Figure 3 The relative height of the arc segment placed vertically with the scalp from top to bottom and parallel to the Z axis is Rh. These two parameters determine the degree of curvature of the arc part of the coil; the structure of a single stimulation coil is determined by these four main characteristic parameters: the length Rx of the straight long axis segment, the relative height Rh, the coil winding height Rz and the coil width Width. In addition to these four main characteristic parameters, the height difference d of the upper and lower coils will also affect the superposition and focusing of the induced electric field generated by the overlapping coils in the skull. The excitation current of the lower stimulation coil 1 and the upper stimulation coil 2 is as follows: Figure 1 As shown by the black arrow in (a), the excitation current passed through the lower stimulation coil 1 is represented as i1, and the excitation current passed through the upper stimulation coil 2 is represented as i2, and the angles between the upper and lower stimulation coils and the Y axis are equal. The angle of overlap between the lower stimulation coil 1 and the upper stimulation coil 2 is the sum of the angles between the two coils and the Y axis. Let the overlap angle be α, as shown in FIG. Figure 1 In addition, the lower stimulation coil 1 and the upper stimulation coil 2 can overlap at different angles, and the sizes of the two coils can be the same or different (coils of different sizes and overlapping angles will have different stimulation effects).

[0051] Preferably, it also includes but is not limited to an annular shielding plate 3 for wrapping the lower stimulation coil 1 and the upper stimulation coil 2 and having an opening 30 at the bottom. Figure 4As shown, overlapping coils can be placed inside the annular shielding plate 3 to form a package to achieve the effect of improving the focusing. Specifically, the annular shielding plate 3 can be, but is not limited to, made of thin silicon steel sheets stacked together, so that by taking advantage of the characteristics of the silicon steel sheets, not only the resistivity is improved and the loss of eddy current is reduced, but also the focusing effect is improved. Assuming the scalp vertex as the origin, in order to meet the stimulation depth requirements, the XY plane 20 mm below the scalp is taken as the bio-electromagnetic stimulation target area 100, and along the X test line (y = 0, z = -20 mm), the Y test line (x = 0, z = -20 mm), and the Z test line (x = 0, y = 0), the distribution characteristics of the induced electric field space of the target area induction plane are extracted: the induced electric field value generated by the stimulation coil in the brain is called the stimulation intensity, and the maximum value E of the Y component of the induced electric field in the target area is used. ymax Indicates that the stimulation depth indicates the penetration ability of the induced electric field in the brain. The intracranial induced electric field decays from the scalp vertex along the Z test line. When the induced electric field intensity decays to Times E ymax The stimulation depth can be extracted from the Z test line; focusing refers to the ability of the induced electric field to focus on a certain area, which can be used when the maximum induced electric field value E on the target area is greater than ymax of The smaller the ratio, the better the focusing. To evaluate the stimulation effect, we generally compare the above aspects, and by properly selecting the above performance indicators, we can improve the stimulation effect to a greater extent.

[0052] Examples of comparisons of stimulation effects based on different coil widths and different overlap angles are shown below. Figure 5 As shown: Take the overlapping coil with specific parameters, whose parameters are Rx = Rh = 40mm, Rz = 6mm, keep d = 1mm, the excitation current amplitude I1 = I2 = 5000A, and the frequency f = 5000Hz unchanged. Figure 5 As shown in (a), horizontal observation: for a certain stimulation coil width Width, the stimulation intensity of the intracranial target area decreases with the increase of the stimulation coil overlap angle α. When Width = 12mm, α increases from 60° to 120°, and the stimulation intensity of the intracranial target area decreases from 168.12V / m to 102.36V / m; longitudinal observation: for each certain overlap angle α, the stimulation intensity of the intracranial target area also shows an increasing trend with the increase of the coil width Width. When α = 90°, Width increases from 9mm to 15mm, and the stimulation intensity of the intracranial target area increases from 108.23V / m to 171.53V / m, with an overall increase of 58.46%. Figure 5As shown in (b), when viewed laterally, for a given stimulation coil width, the focal area of the intracranial target decreases with the increase of the stimulation coil overlap angle α. When Width = 12 mm, α increases from 60° to 120°, and the focal area of the intracranial target decreases from 26.33 cm 2 Reduced to 25.25cm 2 , an overall improvement of 4.1%; longitudinal observation: for each determined overlap angle α, the focal area of the intracranial target area gradually increases with the increase of width Width. When α=90°, the width increases from 9mm to 15mm, and the focal area of the intracranial target area increases from 25.21cm 2 Increased to 26.54cm 2 In summary, changes in the coil width Width and the overlap angle α not only change the stimulation intensity, but are also beneficial to the focus of the stimulation. Therefore, preferably, the lower stimulation coil 1 and the upper stimulation coil 2 are also used to adjust the stimulation intensity and stimulation focus of the bio-electromagnetic stimulation target area 100 through different overlap angles and / or coil widths.

[0053] An example of comparing the difference in electric field strength generated by different stimulation currents is shown below. Figure 6 As shown: Take the overlapping coils with specific parameters, whose parameters are Rx = Rh = 40mm, Rz = 6mm, keep d = 1mm, overlap angle α = 90°, frequency f = 5000Hz unchanged, the excitation current amplitude of the upper stimulation coil 2 remains unchanged and i2 = 5000A, take the excitation current amplitude i1 of the lower stimulation coil 1 from 5000A to 2500A, and the difference between the two excitation currents Δi = [0kA, 0.5kA, 1kA, 1.5kA, 2kA, 2.5kA]. Figure 6 As shown, as the difference between the two pulse currents increases, the intensity of the intracranial induced electric field decreases accordingly, from 141.05 V / m to 97.67 V / m, indicating that as the amplitude of the pulse current of the upper and lower stimulation coils changes, the directional shift of the target area can also be effectively achieved. Preferably, the lower stimulation coil 1 and the upper stimulation coil 2 are also used to adjust the degree of directional shift of the bio-electromagnetic stimulation target area 100 through excitation currents of different sizes.

[0054] An example of a comparison of the induced electric field distribution generated by the overlapping stimulation coil assembly and the traditional coil is shown below. Figure 7 As shown: When the excitation current amplitude is 5000A and the total number of coil turns n=8, Figure 7 (a) in the figure shows that compared with the traditional figure eight coil, the overlapping coil effectively suppresses the negative peak of the induced electric field, making it more advantageous in generating a more concentrated induced electric field. Figure 7Figure (b) shows that under the same stimulation conditions, at the same stimulation depth point a, the attenuation of the induced electric field with the overlapping coil is significantly less than that with the traditional figure-eight coil. Assuming 50 V / m as the minimum stimulation intensity required to reach the nerve stimulation threshold, it can be seen that the stimulation depth point b with the traditional figure-eight coil is less than the stimulation depth point c with the overlapping coil, indicating that the overlapping coil can achieve both improved stimulation depth and improved stimulation depth.

[0055] An example of a comparison of the induced electric field distribution generated by the overlapping stimulation coil assembly and the traditional coil in the intracranial target plane is shown below. Figure 8 As shown in the figure: When the excitation current amplitude is 5000A, the inner diameter of the coil is 34mm, and the total number of turns is n=8, Figure 8 As shown in (a) and (b), the stimulation intensity of the figure-eight coil is E max =169.22V / m, stimulation area 27.27cm 2 When the excitation current amplitude of the upper and lower stimulation coils is 5000A, Rx=Rh=40mm, Rz=6mm, d=1mm, overlap angle α=90°, and total number of turns n=8, Figure 8 As shown in (c) and (d), the stimulation intensity of the overlapping coil is E ymax =144.74V / m, stimulation area 24.44cm 2 It can be seen that under the premise of reaching the nerve stimulation threshold, the induced electric field distribution generated by the overlapping coil is more ideal than that of the traditional figure-eight coil, and its focusing is improved by 10.4%, that is, the stimulation area is effectively reduced while the stimulation depth is increased.

[0056] like Figure 9As shown, the second aspect of this embodiment provides a coil overlapping stimulation system using the overlapping stimulation coil assembly described in the first aspect, including but not limited to a control module AD1, a first charging power module DC1, a second charging power module DC2, a first energy storage capacitor C1, a second energy storage capacitor C2, a first discharge switch K1, a second discharge switch K2, a first discharge circuit FD1, a second discharge circuit FD2 and the overlapping stimulation coil assembly for bio-electromagnetic stimulation as described in the first aspect, wherein the output end of the control module AD1 is electrically connected to the controlled ends of the first charging power module DC1, the second charging power module DC2, the first discharge switch K1 and the second discharge switch K2 respectively; The positive output end of the first charging power module DC1 is electrically connected to one end of the first energy storage capacitor C1 and one end of the first discharge switch K1, respectively. The other end of the first discharge switch K1 is electrically connected to the positive input end of the first discharge circuit FD1. The negative output end of the first charging power module DC1 is electrically connected to the other end of the first energy storage capacitor C1 and the negative input end of the first discharge circuit FD1, respectively. The positive output end of the first discharge circuit FD1 is electrically connected to the excitation current introduction end of the lower stimulation coil 1 in the overlapping stimulation coil assembly, and the negative output end of the first discharge circuit FD1 is electrically connected to the excitation current lead-out end of the lower stimulation coil 1. The second charging power module DC1 is electrically connected to the positive input end of the first discharge circuit FD1. The positive output end of the module DC2 is electrically connected to one end of the second energy storage capacitor C2 and one end of the second discharge switch K2, the other end of the second discharge switch K2 is electrically connected to the positive input end of the second discharge circuit FD2, the negative output end of the second charging power module DC2 is electrically connected to the other end of the second energy storage capacitor C2 and the negative input end of the second discharge circuit FD2, the positive output end of the second discharge circuit FD2 is electrically connected to the excitation current introduction end of the upper stimulation coil 2 in the overlapping stimulation coil assembly, and the negative output end of the second discharge circuit FD2 is electrically connected to the excitation current lead-out end of the upper stimulation coil 2; the first charging power module DC1 is used The first discharge circuit FD1 is configured to control the first discharge switch K1 to conduct when the voltage across the first energy storage capacitor C1 reaches a first expected value, thereby discharging the first energy storage capacitor C1 through the first discharge circuit FD1; and the second discharge switch K2 is configured to conduct when the voltage across the second energy storage capacitor C2 reaches a second expected value, thereby discharging the second energy storage capacitor C2 through the second discharge circuit FD2;The first discharge circuit FD1 is used to send a first excitation current to the lower stimulation coil 1 when the first energy storage capacitor C1 is discharged; the second discharge circuit FD2 is used to send a second excitation current to the upper stimulation coil 2 when the second energy storage capacitor C2 is discharged.

[0057] like Figure 9 As shown, in the specific structure of the coil overlapping stimulation system, the control module is used as the system control center, which can adjust the excitation current of the upper and lower stimulation coils within a certain range to shift the stimulation area to the left or right, and it can achieve the purpose of repeated stimulation by controlling the charging power module and the discharge switch, and it can be specifically implemented by a microcontroller of the STM32F105 series. In addition, the aforementioned first charging power module DC1, the second charging power module DC2, the first energy storage capacitor C1, the second energy storage capacitor C2, the first discharge switch K1, the second discharge switch K2, the first discharge circuit FD1 and the second discharge circuit FD2 can all be implemented using existing devices or corresponding circuits. Preferably, it also includes a first clamping diode D1 connected in parallel with the first energy storage capacitor C1 and / or a second clamping diode D2 connected in parallel with the second energy storage capacitor C2, such as Figure 9 As shown, the diode clamping can be used to prepare for subsequent stimulation. Preferably, an information acquisition module SC1 is further included that is communicatively connected to the control module AD1. The information acquisition module SC1 is configured to acquire electrophysiological response information generated by the stimulation when the bioelectromagnetic stimulation target area 100 is stimulated, and transmit the electrophysiological response information to the control module for information analysis. Furthermore, the first discharge switch K1 or the second discharge switch K2 preferably utilizes a thyristor to take advantage of its low loss and facilitate energy conservation.

[0058] The working process, working details and technical effects of the aforementioned system provided in the second aspect of this embodiment can be found in the overlapping stimulation coil assembly described in the first aspect, and will not be described in detail here.

[0059] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A coil overlapping stimulation system, characterized in that: The invention comprises a control module (AD1), a first charging power module (DC1), a second charging power module (DC2), a first energy storage capacitor (C1), a second energy storage capacitor (C2), a first discharge switch (K1), a second discharge switch (K2), a first discharge circuit (FD1), a second discharge circuit (FD2), and an overlapping stimulation coil assembly for bio-electromagnetic stimulation, wherein the output end of the control module (AD1) is electrically connected to the controlled ends of the first charging power module (DC1), the second charging power module (DC2), the first discharge switch (K1), and the second discharge switch (K2); The overlapping stimulation coil assembly comprises a lower stimulation coil (1) and an upper stimulation coil (2) for vertically placing above a bioelectromagnetic stimulation target area (100), wherein the lower stimulation coil (1) and the upper stimulation coil (2) have the same geometric structure and a semicircular coil structure; the lower stimulation coil (1) and the upper stimulation coil (2) are arranged in an overlapping manner, and the arc portion of the lower stimulation coil (1), the arc portion of the upper stimulation coil (2), the straight long axis portion of the lower stimulation coil (1) and the straight long axis portion of the upper stimulation coil (2) are arranged in sequence from bottom to top; the lower stimulation coil (1) and the upper stimulation coil (2) are used to respectively access an excitation current through different discharge circuits to jointly exert a bioelectromagnetic stimulation effect on the bioelectromagnetic stimulation target area (100); The positive output end of the first charging power module (DC1) is electrically connected to one end of the first energy storage capacitor (C1) and one end of the first discharge switch (K1), the other end of the first discharge switch (K1) is electrically connected to the positive input end of the first discharge circuit (FD1), the negative output end of the first charging power module (DC1) is electrically connected to the other end of the first energy storage capacitor (C1) and the negative input end of the first discharge circuit (FD1), the positive output end of the first discharge circuit (FD1) is electrically connected to the excitation current introduction end of the lower stimulation coil (1) in the overlapping stimulation coil assembly, and the negative output end of the first discharge circuit (FD1) is electrically connected to the excitation current lead-out end of the lower stimulation coil (1); The positive output end of the second charging power module (DC2) is electrically connected to one end of the second energy storage capacitor (C2) and one end of the second discharge switch (K2), the other end of the second discharge switch (K2) is electrically connected to the positive input end of the second discharge circuit (FD2), the negative output end of the second charging power module (DC2) is electrically connected to the other end of the second energy storage capacitor (C2) and the negative input end of the second discharge circuit (FD2), the positive output end of the second discharge circuit (FD2) is electrically connected to the excitation current introduction end of the upper stimulation coil (2) in the overlapping stimulation coil assembly, and the negative output end of the second discharge circuit (FD2) is electrically connected to the excitation current lead-out end of the upper stimulation coil (2); The first charging power module (DC1) is used to convert alternating current into a first direct current and output it under the control of the control module (AD1); The second charging power module (DC2) is used to convert the alternating current into a second direct current and output it under the control of the control module (AD1); The control module (AD1) is configured to control the first discharge switch (K1) to be turned on when the voltage across the first energy storage capacitor (C1) reaches a first expected value, so as to discharge the first energy storage capacitor (C1) through the first discharge circuit (FD1); and to control the second discharge switch (K2) to be turned on when the voltage across the second energy storage capacitor (C2) reaches a second expected value, so as to discharge the second energy storage capacitor (C2) through the second discharge circuit (FD2); The first discharge circuit (FD1) is used to send a first excitation current to the lower stimulation coil (1) when the first energy storage capacitor (C1) is discharged; The second discharge circuit (FD2) is used to send a second excitation current to the upper stimulation coil (2) when the second energy storage capacitor (C2) is discharged.

2. The coil overlapping stimulation system according to claim 1, wherein: It also includes a first clamping diode (D1) connected in parallel with the first energy storage capacitor (C1) and / or a second clamping diode (D2) connected in parallel with the second energy storage capacitor (C2).

3. The overlapping coil stimulation system according to claim 1, wherein: The invention also includes an information acquisition module (SC1) communicatively connected to the control module (AD1), wherein the information acquisition module (SC1) is used to acquire electrophysiological response information generated by the stimulation when the bioelectromagnetic stimulation target area (100) is stimulated, and transmit the electrophysiological response information to the control module for information analysis.

4. The overlapping coil stimulation system according to claim 1, wherein: The first discharge switch (K1) or the second discharge switch (K2) is a thyristor.

5. The overlapping coil stimulation system according to claim 1, wherein: The lower stimulation coil (1) or the upper stimulation coil (2) adopts a multi-layer multi-turn coil structure, and the excitation current flows into the lead-in end of the outer straight long axis segment of the multi-layer multi-turn coil structure, and then flows out from the lead-out end of the inner circular arc segment of the multi-layer multi-turn coil structure.

6. The overlapping coil stimulation system according to claim 1, wherein: The lower stimulation coil (1) and the upper stimulation coil (2) are also used to adjust the stimulation intensity and stimulation focus of the bioelectromagnetic stimulation target area (100) through different overlapping angles and / or coil widths.

7. The overlapping coil stimulation system according to claim 1, wherein: The lower stimulation coil (1) and the upper stimulation coil (2) are also used to adjust the degree of directional deviation of the bio-electromagnetic stimulation target area (100) through excitation currents of different magnitudes.

8. The overlapping coil stimulation system according to claim 1, wherein: It also includes an annular shielding plate (3) for wrapping the lower stimulation coil (1) and the upper stimulation coil (2) and having an opening (30) at the bottom.

9. The overlapping coil stimulation system according to claim 8, wherein: The annular shielding plate (3) is formed by stacking thin silicon steel sheets.

Images