A Transcranial Magnetic Stimulation System and Method

Abstract

The present application discloses a transcranial magnetic stimulation system and method. First, three-dimensional reconstruction is performed on the acquired medical image data; then, a corresponding relationship is established between the reconstructed virtual three-dimensional model and the spatial positioning coordinate system of the positioning and fixing connection device; then, according to the spatial position relationship between the three-dimensional model of the landmark area and the three-dimensional model of the target area in the virtual three-dimensional model, the target coordinates of the target area to be magnetically stimulated inside the skull in the spatial positioning coordinate system are obtained; finally, the magnetic stimulation device is fixedly connected to the positioning and fixing connection device, so as to perform magnetic stimulation on the target area through the first electromagnetic generating coil group of the magnetic stimulation device. Because the target area deep in the brain is accurately positioned based on medical images, and then the magnetic stimulation intensity is accurately controlled through the dual-focus magnetic stimulation coil, the transcranial magnetic stimulation is more accurate, and the stimulation depth and range are more controllable. On the premise of greatly improving the treatment effect of transcranial magnetic stimulation, the complications caused by magnetic stimulation are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of biomedical engineering, and particularly to a transcranial magnetic stimulation system and method. Background Art

[0002] Transcranial magnetic stimulation (TMS) is an important technology in the field of biomedical engineering. It is a technology based on the principle of electromagnetic induction of the brain electric field. Through high-field pulsed electromagnetic fields, it can penetrate the skull and act on nerve tissues at deeper positions for nerve stimulation and nerve regulation. Moreover, it does not require installing devices through the skin and has advantages such as non-invasive and painless. The magnetic field used for TMS can have an intensity and density sufficient to depolarize neurons. And when TMS pulses are repeatedly applied, when the selected magnetic stimulation parameters (frequency, amplitude, pulse width, pulse width gradient, etc.) are used, transcranial magnetic stimulation can regulate the excitability of the cerebral cortex, and even regulate the excitability of the cortex throughout the stimulation period. In the past few decades, the application of TMS in studying the cognition of various nervous system and mental diseases, the relationship between brain and behavior, and pathophysiology has increased rapidly.

[0003] In the existing transcranial magnetic stimulation systems used in the prior art, during actual use, transcranial magnetic stimulation may have adverse side effects such as slight pain, discomfort, mental fluctuations, fainting, syncope, and even induce epileptic seizures. The main reasons for these adverse side effects are that the stimulation range of TMS is large, and the selection of magnetic stimulation power and magnetic stimulation method is inappropriate, etc. Among them, the most important reason is that the magnetic stimulation target is not accurately positioned, and it cannot accurately target the magnetic stimulation target or area for accurate positioning, and thus cannot achieve accurate quantitative and range-defined magnetic stimulation. Summary of the Invention

[0004] The main technical problem to be solved by the present invention is that the magnetic stimulation coil in the existing transcranial magnetic stimulation device has a shallow stimulation depth and cannot perform magnetic focusing, thus unable to achieve precise magnetic stimulation of the deep target area and precise control of the magnetic stimulation intensity.

[0005] According to a first aspect, in one embodiment, a transcranial magnetic stimulation system is provided, including:

[0006] An image acquisition module, configured to acquire medical image data; the medical image data includes images of the target area to be magnetically stimulated inside the skull and images of the marker area for target positioning;

[0007] A model reconstruction module, configured to perform three-dimensional reconstruction on the medical image data to obtain a virtual three-dimensional model; the virtual three-dimensional model includes a three-dimensional model of the target area after three-dimensional reconstruction of the target area, and the virtual three-dimensional model further includes a three-dimensional model of the marker area after three-dimensional reconstruction of the marker area;

[0008] A positioning and fixing connection device is used to establish a spatial positioning coordinate system and fixedly connect the head in the spatial positioning coordinate system;

[0009] A target point coordinate acquisition module is used to establish a corresponding relationship between the three-dimensional model of the marked area in the virtual three-dimensional model and the marked area in the spatial positioning coordinate system, and obtain the coordinate value of the target area to be magnetically stimulated inside the head in the spatial positioning coordinate system according to the spatial position relationship between the three-dimensional model of the marked area and the three-dimensional model of the target area in the virtual three-dimensional model, and use this coordinate value as the target point coordinate;

[0010] A magnetic stimulation device is used to be fixedly connected to the positioning and fixing connection device; the magnetic stimulation device includes a first electromagnetic generating coil group, the first electromagnetic generating coil group includes two first coils with the same structure, the two first coils are symmetrically arranged about the center on the positioning and fixing connection device, and the center of symmetry is located at the target point coordinate; the two symmetrically arranged first coils of the first electromagnetic generating coil group form a pair of dual-focusing magnetic stimulation coil pairs, emitting electromagnetic waves towards the center of symmetry to magnetically stimulate the target area.

[0011] In one embodiment, the positioning and fixing connection device includes a spherical fixing frame that can be disassembled into two completely identical hemispherical shapes. At least one circular guide rail is provided on the spherical fixing frame, and the center of each circular guide rail is located on the same straight line passing through the center point of the spherical fixing frame; the first electromagnetic generating coil group is fixedly connected to the positioning and fixing connection device through the circular guide rail.

[0012] In one embodiment, three circular guide rails are provided on the spherical fixing frame, and the circular planes where each circular guide rail is located are 60 degrees to each other.

[0013] In one embodiment, at least two coil fixing interfaces are provided on each guide rail, and each coil fixing interface is evenly distributed on the circular guide rail. The coil fixing interface is used to fixedly connect the first coil and the circular guide rail.

[0014] In one embodiment, the magnetic stimulation device includes a second electromagnetic generating coil group, the second electromagnetic generating coil group includes two second coils with the same structure, the two second coils are symmetrically arranged about the center on the positioning and fixing connection device, and the center of symmetry is located at the target point coordinate; the diameter of the second coil is smaller than that of the first coil; the two symmetrically arranged second coils of the second electromagnetic generating coil group form a pair of dual-focusing magnetic stimulation coil pairs, emitting electromagnetic waves towards the center of symmetry to magnetically stimulate the target area.

[0015] In one embodiment, the shape of the first coil is oval, circular or figure-eight;

[0016] and / or, the shape of the second coil is oval, circular or figure-eight.

[0017] In one embodiment, the magnetic stimulation device further includes a stimulation driving and control module, electrically connected to the first electromagnetic generating coil group; the magnetic stimulation device is configured to perform timing control of the driving current on the two first coils or one of the first coils according to a preset coil stimulation intensity and stimulation timing.

[0018] In one embodiment, the acquisition formula of the coil stimulation intensity includes:

[0019] B = 0.5×μ 0 ×N×I×R 2 ×[R 2 + (d / 2 + x) 2 -（3 / 2） ;

[0020] μ 0 = 4×π×10 -7 Tm / A;

[0021] wherein, N is the number of turns of the first coil, I is the coil current, R is the radius of the effective equivalent circular area of the first coil, x is the distance from the central symmetry point of the first coil to the center of the effective circle of the first coil, and d is the width of the first coil.

[0022] According to a second aspect, in one embodiment, a transcranial magnetic stimulation system method is provided, including:

[0023] Obtaining medical image data; the medical image data includes images of the target area to be magnetically stimulated inside the skull and images of the marker area for target positioning;

[0024] Performing three-dimensional reconstruction on the medical image data to obtain a virtual three-dimensional model; the virtual three-dimensional model includes the three-dimensional model of the target area after three-dimensional reconstruction of the target area, and the virtual three-dimensional model further includes the three-dimensional model of the marker area after three-dimensional reconstruction of the marker area;

[0025] Establishing a spatial positioning coordinate system through a positioning and fixing connection device, and fixing and connecting the skull in the spatial positioning coordinate system;

[0026] ​Establish a corresponding relationship between the three-dimensional model of the marked area in the virtual three-dimensional model and the marked area in the spatial positioning coordinate system; then, based on the spatial position relationship between the three-dimensional model of the marked area and the three-dimensional model of the target area in the virtual three-dimensional model, obtain the coordinate value of the target area to be magnetically stimulated inside the skull in the spatial positioning coordinate system, and use this coordinate value as the target coordinate;

[0027] Fix the magnetic stimulation device to the positioning and fixing connection device; the magnetic stimulation device includes a first electromagnetic generating coil group, the first electromagnetic generating coil group includes two first coils with the same structure, and the two first coils are symmetrically arranged on the positioning and fixing connection device in a central symmetry manner, and the central symmetry point is located at the target coordinate;

[0028] Form a pair of dual-focus magnetic stimulation coil pairs through the first electromagnetic generating coil group of the magnetic stimulation device, and emit electromagnetic waves to the central symmetry point to magnetically stimulate the target area.

[0029] According to the transcranial magnetic stimulation system of the above embodiment, due to the precise positioning of the target area in the depth of the brain based on medical images, and then the precise control of the magnetic stimulation intensity through the pair of dual-focus magnetic stimulation coil pairs, the transcranial magnetic stimulation is more accurate, and the stimulation depth and stimulation range are more controllable. On the premise of greatly improving the treatment effect of transcranial magnetic stimulation, the complications caused by magnetic stimulation are reduced. Description of the Drawings

[0030] Figure 1 It is a schematic structural connection diagram of a transcranial magnetic stimulation system in an embodiment;

[0031] Figure 2 It is a schematic structural diagram of a positioning and fixing connection device in an embodiment;

[0032] Figure 3 It is a schematic structural diagram of a circular guide rail in an embodiment;

[0033] Figure 4 It is a schematic flow diagram of a transcranial magnetic stimulation method in an embodiment;

[0034] Figure 5 It is a schematic diagram of transcranial magnetic stimulation in another embodiment;

[0035] Figure 6 It is a schematic flow diagram of a transcranial magnetic stimulation method in another embodiment;

[0036] Figure 7 It is a schematic flow diagram of a transcranial magnetic stimulation method in another embodiment. Detailed Embodiments

[0037] The present invention will be further described in detail below in conjunction with the accompanying drawings through specific embodiments. Similar elements in different embodiments are denoted by related similar element numbers. In the following embodiments, many details are described to enable a better understanding of the present application. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other elements, materials, or methods. In some cases, some operations related to the present application are not shown or described in the specification in order to avoid the core part of the present application being overwhelmed by excessive description. For those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0038] In addition, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can also be reordered or adjusted in a manner obvious to those skilled in the art. Therefore, the various sequences in the specification and drawings are only for clearly describing a certain embodiment and do not mean that they are the necessary sequences, unless it is stated that a certain sequence must be followed.

[0039] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the described objects and do not have any sequential or technical meaning. And the "connection" and "coupling" mentioned in the present application, unless otherwise specified, both include direct and indirect connection (coupling).

[0040] In the prior art, the usual depth of transcranial magnetic brain stimulation is generally about 1-3 cm, which can only stimulate the superficial areas of the brain and is difficult to reach the deep areas of the brain such as the frontal lobe, thalamus, cingulate gyrus, putamen, caudate nucleus, hippocampus, ventral striatum, and amygdala, or it is difficult to perform precise magnetic stimulation on the deep areas of the brain. Just by increasing the magnetic field strength of the transcranial magnetic stimulation coil, adverse effects such as headache, syncope, and even induced epilepsy limit the application of transcranial magnetic brain stimulation. It is of great significance to urgently develop a new type of transcranial magnetic stimulator device with the ability of deep brain magnetic stimulation or deep focus type magnetic stimulation function.

[0041] In TMS technology, brief magnetic pulses are used to cause depolarization of targeted neurons in the brain using Faraday's law of electromagnetic induction. When TMS is performed in a repetitive manner (referred to as rTMS), long-term potentiation-like or depression-like effects on the nervous system can be achieved. Conventional magnetic stimulation techniques and coils are mostly designed for surface stimulation of brain tissue, but generally cannot apply deeper stimulation. Since surface stimulation does not cause effective stimulation of the ventral prefrontal cortex and other reward- and emotion-related brain structures (such as the nucleus accumbens (ventral striatum)), it is predictable that deeper brain stimulation can more effectively treat major depressive disorder and other psychiatric and neurological diseases. Stimulating deep brain regions (dTMS), known as deep TMS, requires high intensity and accuracy, which cannot be achieved by current available conventional magnetic stimulators using standard coil configurations without causing unwanted side effects (such as seizures or other problems associated with overstimulating cortical regions). In the past, the rTMS process could not directly stimulate targets more than 2 cm below the skull surface. Deep rTMS technology is being developed to improve the depth penetration of the electromagnetic field using an H-coil, in which multiple windings are arranged such that the resulting magnetic fields converge to allow direct simulation up to 4 cm below the skull surface.

[0042] Over the past decade, advances in functional imaging have identified specific brain regions with altered activity and volume associated with specific psychiatric symptoms and syndromes, which may bridge the theoretical gap between the diseases of psychiatry and the neurological diseases of the brain for both patients and caregivers (Downar and Daskalakis 2013; Zhang et al., 2014). Corresponding advances in bioengineering have enabled non-invasive modulation of these altered brain regions via dTMS, thus forming an effective and logical treatment widely used in psychiatric patients and overall reducing the stigma of mental illness.

[0043] Although deep stimulation can also be accomplished with large circular coils or double-cone coils, their electromagnetic fields decay more severely than those of the H-coil and to reach deep targets, higher intensities must be used on the surface than with the H-coil (Roth et al., 2007; Pell et al., 2011). Higher intensities may be unpleasant and potentially unsafe for patients. The H-coil stimulates a wider area than the figure-eight coil, which eliminates the need for imaging and neuronavigation; without navigation, conventional rTMS misses the target in 27 - 32% of patients, making conventional rTMS treatment expensive due to the high number needed to achieve remission (number needed to treat (NNT)) (Johnson et al., 2013; George et al., 2010). The H-coil stimulates a larger area (18 cm compared to 3 cm for conventional coils) 3 compared to 3 cm for conventional coils).3 ) and the ability of deeper structures are the reasons for effectively treating dTMS synchronously with the H-coil.

[0044] In an embodiment of the present invention, a transcranial magnetic stimulation system is disclosed, which includes an image acquisition module, a model reconstruction module, a positioning and fixing connection device, a target coordinate acquisition module, and a magnetic stimulation device. The image acquisition module is used to acquire medical image data, the model reconstruction module is used to perform three-dimensional reconstruction on the medical image data to obtain a virtual three-dimensional model, the positioning and fixing connection device is used to establish a spatial positioning coordinate system and fix and connect the head in the spatial positioning coordinate system, the target coordinate acquisition module is used to obtain the coordinate values of the target area to be magnetically stimulated inside the head in the spatial positioning coordinate system according to the virtual three-dimensional model, and the magnetic stimulation device is used to perform magnetic stimulation on the target area. Since the target area in the depth of the brain is accurately positioned based on medical images, and then the magnetic stimulation intensity is accurately controlled by an even-focusing magnetic stimulation coil, the transcranial magnetic stimulation is more accurate and the stimulation range is more controllable. On the premise of greatly improving the treatment effect of transcranial magnetic stimulation, the complications caused by magnetic stimulation are reduced, which is of great significance in the research of brain science and neuroscience.

[0045] Embodiment 1

[0046] Please refer to Figure 1, which is a schematic structural connection diagram of a transcranial magnetic stimulation system in an embodiment. The transcranial magnetic stimulation system includes an image acquisition module 1, a model reconstruction module 2, a positioning and fixing connection device 3, a target coordinate acquisition module 4, and a magnetic stimulation device 5. The image acquisition module 1 is used to acquire medical image data. The medical image data includes images of the target area to be magnetically stimulated inside the skull and images of the landmark area for target positioning. The model reconstruction module 2 is used to perform three-dimensional reconstruction on the medical image data to obtain a virtual three-dimensional model. The virtual three-dimensional model includes the three-dimensional model of the target area after three-dimensional reconstruction of the target area, and the virtual three-dimensional model also includes the three-dimensional model of the landmark area after three-dimensional reconstruction of the landmark area. The positioning and fixing connection device 3 is used to establish a spatial positioning coordinate system and fix and connect the skull in the spatial positioning coordinate system. The target coordinate acquisition module 4 is used to establish a corresponding relationship between the three-dimensional model of the landmark area in the virtual three-dimensional model and the landmark area in the spatial positioning coordinate system, and obtain the coordinate value of the target area to be magnetically stimulated inside the skull in the spatial positioning coordinate system based on the spatial position relationship between the three-dimensional model of the landmark area and the three-dimensional model of the target area in the virtual three-dimensional model, and use this coordinate value as the target coordinate. The magnetic stimulation device 5 is used to be fixedly connected to the positioning and fixing connection device. The magnetic stimulation device 5 includes a first electromagnetic generating coil group. The first electromagnetic generating coil group includes two first coils with the same structure. The two first coils are symmetrically arranged about the center on the positioning and fixing connection device, and the center of symmetry is located at the target coordinate. The two symmetrically arranged first coils of the first electromagnetic generating coil group form a dual-focusing magnetic stimulation coil pair, which emits electromagnetic waves towards the center of symmetry to magnetically stimulate the target area. Any one of the first coils for focused magnetic stimulation in the first electromagnetic generating coil group emits electromagnetic waves towards its own center of symmetry, and multiple first coils for focused magnetic stimulation can simultaneously excite the magnetic field to enhance and focus the magnetic stimulation on the target area.

[0047] Please refer to Figure 2 , which is a schematic structural diagram of the positioning and fixing connection device in an embodiment. The positioning and fixing connection device includes a spherical fixing frame that can be disassembled into two identical hemispherical shapes. At least one circular guide rail 31 is provided on the spherical fixing frame, and the center of each circular guide rail 31 is located on the same straight line passing through the center point of the spherical fixing frame. The first electromagnetic generating coil group is fixedly connected to the positioning and fixing connection device through the circular guide rail 31.

[0048] In one embodiment, three circular guide rails 31 are provided on the spherical fixing frame, and the circular planes where each circular guide rail 31 is located are mutually at an angle of 60 degrees.

[0049] Please refer to Figure 3, which is a schematic structural diagram of a circular guide rail in an embodiment. At least two coil fixing interfaces 32 are provided on each circular guide rail 31, and each coil fixing interface 32 is evenly distributed on the circular guide rail 31. The coil fixing interface 32 is used to fixedly connect the first coil and the circular guide rail 31.

[0050] In one embodiment, the magnetic stimulation device includes a second electromagnetic generating coil group. The second electromagnetic generating coil group includes two second coils with the same structure. The two second coils are symmetrically arranged on the positioning and fixing connection device, and the center of symmetry is located at the target coordinates. The diameter of the second coil is smaller than that of the first coil. The two symmetrically arranged second coils of the second electromagnetic generating coil group form a pair of dual-focus magnetic stimulation coil pairs, which emit electromagnetic waves towards the center of symmetry to perform magnetic stimulation on the target area. Any one of the second coils for focused magnetic stimulation in the second electromagnetic generating coil group emits electromagnetic waves towards its corresponding center of symmetry, and multiple second coils for focused magnetic stimulation can simultaneously excite the magnetic field to enhance and focus the magnetic stimulation on the target area.

[0051] In one embodiment, the shape of the first coil is oval, circular or figure-eight. In one embodiment, the shape of the second coil is oval, circular or figure-eight.

[0052] In one embodiment, the magnetic stimulation device further includes a stimulation drive control module, which is electrically connected to the first electromagnetic generating coil group. The magnetic stimulation device is used to perform timing control of the drive current on two first coils or one of the first coils simultaneously according to the preset coil stimulation intensity and stimulation timing. The acquisition formula of the coil stimulation intensity includes:

[0053] B = 0.5×μ 0 ×N×I×R 2 ×[R 2 + (d / 2 + x) 2 -（3 / 2） ;

[0054] μ 0 = 4×π×10 -7 Tm / A;

[0055] Wherein, N is the number of turns of the first coil, I is the coil current, R is the radius of the effective equivalent circular area of the first coil, x is the distance from the center of symmetry of the first coil to the center of the effective circle of the first coil, and d is the width of the first coil.

[0056] Please refer to Figure 4 , which is a schematic flowchart of a transcranial magnetic stimulation method in an embodiment. In one embodiment of the present application, a transcranial magnetic stimulation method is also disclosed, including:

[0057] Step 110, obtaining medical image data. ​

[0058] Medical imaging data includes images of the target area to be magnetically stimulated inside the skull and images of the landmark area for target localization.

[0059] Step 120: Obtain a virtual three-dimensional model.

[0060] Perform three-dimensional reconstruction on the medical imaging data to obtain a virtual three-dimensional model. The virtual three-dimensional model includes the three-dimensional model of the target area after three-dimensional reconstruction of the target area, and the virtual three-dimensional model also includes the three-dimensional model of the landmark area after three-dimensional reconstruction of the landmark area.

[0061] Step 130: Establish a spatial positioning coordinate system.

[0062] Establish a spatial positioning coordinate system through a positioning and fixing connection device, and fix the skull in the spatial positioning coordinate system.

[0063] Step 140: Obtain the target coordinates.

[0064] Establish a corresponding relationship between the three-dimensional model of the landmark area in the virtual three-dimensional model and the landmark area in the spatial positioning coordinate system. Then, based on the spatial position relationship between the three-dimensional model of the landmark area and the three-dimensional model of the target area in the virtual three-dimensional model, obtain the coordinate value of the target area to be magnetically stimulated inside the skull in the spatial positioning coordinate system, and use this coordinate value as the target coordinates.

[0065] Step 150: Connect the magnetic stimulation device.

[0066] Fix and connect the magnetic stimulation device to the positioning and fixing connection device. The magnetic stimulation device includes a first electromagnetic generating coil group. The first electromagnetic generating coil group includes two first coils with the same structure. The two first coils are symmetrically arranged on the positioning and fixing connection device in a central symmetry manner, and the central symmetry point is located on the target coordinates.

[0067] Step 160: Start magnetic stimulation.

[0068] Two symmetrically arranged first coils of the first electromagnetic generating coil group of the magnetic stimulation device form a dual-focusing magnetic stimulation coil pair, and emit electromagnetic waves towards the central symmetry point to perform magnetic stimulation on the target area.

[0069] In an embodiment of the present application, a transcranial magnetic stimulation method is disclosed. First, three-dimensional reconstruction is performed on the acquired medical image data; then, a corresponding relationship is established between the reconstructed virtual three-dimensional model and the spatial positioning coordinate system of the positioning and fixing connection device; then, according to the spatial position relationship between the landmark area three-dimensional model and the target area three-dimensional model in the virtual three-dimensional model, the target coordinates of the target area to be magnetically stimulated inside the skull are obtained in the spatial positioning coordinate system; finally, the magnetic stimulation device is fixedly connected to the positioning and fixing connection device, so as to perform magnetic stimulation on the target area through the first electromagnetic generating coil group of the magnetic stimulation device. Since the target area deep in the brain is accurately positioned based on medical images, and then the magnetic stimulation intensity is accurately controlled through the dual-focus type magnetic stimulation coil, the transcranial magnetic stimulation is more accurate, and the stimulation depth and range are more controllable. On the premise of greatly improving the treatment effect of transcranial magnetic stimulation, the complications caused by magnetic stimulation are reduced.

[0070] Embodiment 2

[0071] Please refer to Figure 5 , which is a schematic diagram of transcranial magnetic stimulation in another embodiment. The magnetic stimulation device includes two first electromagnetic generating coil groups. One first electromagnetic generating coil group includes a first coil 1 and a first coil 2, and the other first electromagnetic generating coil group includes a first coil 3 and a first coil 4. The two first electromagnetic generating coil groups respectively form a dual-focus type deep magnetic stimulation coil group. According to the magnetic stimulation focusing principle of the dual-focus type deep magnetic stimulation coil group, taking a circular coil as an example, the magnetic field intensity generated by a group of dual-focus type deep magnetic stimulation coil groups is approximately:

[0072] B 1 =0.5×μ 0 ×N 1 ×I 1 ×R 1 2 ×[R 1 2 +(d 1 / 2+x 1 ) 2 -（3 / 2） ;

[0073] where x 1 is the distance from a point on the axis to the center of a coil, and the magnetic field direction is along the axis.

[0074] The magnetic field intensity generated by the other group of dual-focus type deep magnetic stimulation coil groups is approximately:

[0075] B 2 =0.5×μ 0 ×N 2 ×I 2 ×R 2 2 ×[R​2 2 +(d 2 / 2 + x 2 ) 2 -（3 / 2） ;

[0076] Wherein, x 2 is the distance from a point on the axis to the center of a coil, and the magnetic field direction is along the axis.

[0077] The spatial intersection point of the axes of two sets of dual-type magnetic stimulation coil sets is the maximum focusing point of the magnetic field intensity, and the magnetic field magnitude at the focusing point is:

[0078] B = (B 1 2 + B 2 2 + 2 × B 1 × B 2 × cosα) 1 / 2 ;

[0079] Wherein, α is the angle between the two axes. The position of the focusing point is completely determined by the axis intersection point of the dual-type magnetic stimulation coil sets, and the stimulation depth (position of the focusing point) and intensity (synthesized magnetic field intensity at the focusing point) of magnetic stimulation can be determined very simply.

[0080] Please refer to Figure 6 , which is a schematic flow chart of a transcranial magnetic stimulation method in another embodiment. The transcranial magnetic stimulation system includes a display and control module, a functional magnetic resonance interface function module, a magnetoencephalogram function module, a coil positioning guidance module, and a mode modulation and drive module. The functional magnetic resonance interface function module detects the functional structural image of the brain of the person to be stimulated and transmits the image information to the coil positioning guidance module. The magnetoencephalogram function module detects the functional magnetoencephalogram image of the person to be stimulated and transmits the image information to the coil positioning guidance module. The coil positioning guidance module calculates the optimal position arrangement plan of the dual-type focused depth magnetic stimulation coil sets on the positioning fixture according to the fMRI brain functional structural image and the magnetoencephalogram functional image of the person to be stimulated and the preset stimulated brain target area of the person to be stimulated, and sends the configuration plan to the output screen of the display and control module and to the mode modulation and drive control module for calculating the optimal coil stimulation mode and excitation.

[0081] The method for positioning dual-type focused magnetic stimulation coils using fMRI brain functional structural images and magnetoencephalogram functional graphs specifically includes:

[0082] Step 1, specifying the target brain area to be detected (left hemisphere or right hemisphere, parietal lobe, temporal lobe, occipital lobe, etc.) before fMRI brain function scanning and magnetoencephalogram detection;

[0083] ​Step 2: Extract and utilize the structural brain image data of the fMRI brain functional image to reconstruct the three-dimensional brain structure diagram of the patient to be detected. When reconstructing the three-dimensional brain structure diagram, it is preferable to use the horizontal plane passing through the highest point at the top of the brain and perpendicular to the brainstem as the reference plane xoy. The highest point at the top of the brain is the three-dimensional coordinate origin o. The x-axis is along the direction of the brain fissures and sulci passing through the three-dimensional coordinate origin o, with the forward direction being the positive direction. The z-axis is the straight line perpendicular to the xoy plane passing through the three-dimensional coordinate origin o, and the downward direction is the positive direction of the z-axis. The y-axis is the straight line perpendicular to the x and z axes passing through the three-dimensional coordinate origin o. Extract the BOLD functional effect data of the fMRI brain functional image and draw an image at the corresponding position of the generated three-dimensional brain structure. Use the BOLD functional effect value of the image and the preset criterion value to depict the target region envelope line (neuroactive target region or neuroinactive target region) of the drawn image.

[0084] Step 3: Activate the coil positioning guidance module, solve for the coil configuration methods in which the axis intersection points of the dual coil pairs in all coil configuration schemes fall within the target region envelope line calculated in Step 2, output and sort the feasible coil configuration methods, and solve for the position coordinates of the magnetic field focusing points for each coil position configuration mode. The preferred sorting principle for the coil configuration mode is: the focusing level takes precedence over the number of focusing points (the focusing level means multiple coil groups focus on one point. For example, if three coil groups focus on the same point, then this focusing point is a level-2 focusing point; if two coil groups focus on the same point, then this focusing point is a level-1 focusing point).

[0085] Please refer to Figure 7 , which is a schematic flow diagram of the transcranial magnetic stimulation method in another embodiment. The mode modulation and drive control module calculates the distance from the stimulation coil to the target stimulation area and the angle between the stimulation coil and the target connection line based on the position configuration of the stimulation coil pair, calculates the required coil stimulation intensity and stimulation timing, and the drive current and timing of each individual magnetic stimulation coil in each individual dual-focusing magnetic stimulation coil pair are exactly the same. The main control module controls the operation of the entire focused deep brain magnetic stimulator, is responsible for establishing the personal file and personal treatment plan of the patient to be stimulated, and improves and optimizes the treatment plan based on the niche evolution optimization algorithm of the fMRI image and magnetoencephalogram characteristics of the target area in the patient's brain. The display and control module is used to input the necessary system control information and output the system operation status information. In one embodiment, the transcranial magnetic stimulation system further includes a communication module, which is responsible for communicating with the mobile terminal and / or the background cloud.

[0086] Taking 8 first coils as magnetic stimulation coils as an example, the process of transcranial stimulation includes:

[0087] 1) The display and control module, under the control of the main control module, establishes the personal file of the person to be stimulated and determines the brain stimulation site of the person to be stimulated.

[0088] 2) The system starts the functional magnetic resonance interface function module and the magnetoencephalogram function module to detect the fMRI brain functional structure image and the magnetoencephalogram functional image of the corresponding brain target area of the person to be stimulated;

[0089] 3) The coil positioning guidance module calculates an optimal position configuration plan for the stimulation coil pair of the direct stimulation target area based on the fMRI brain functional structure image and the magnetoencephalogram functional image information of the corresponding brain target area of the person to be stimulated, and in combination with the number of optional coil pairs and the available coil configuration positions of the positioning fixture;

[0090] 4) After configuring and fixing the magnetic stimulation coil pair, the position configuration information of the stimulation coil pair is input into the system through the display and control module. If it is exactly the same as the stimulation coil pair configuration plan recommended by the coil positioning guidance module, it can be directly determined;

[0091] 5) The mode modulation and drive control module calculates the distance from the magnetic stimulation coil to the stimulation target area and the included angles between the connecting lines of the magnetic stimulation coil and the target area based on the fMRI brain functional structure image, the magnetoencephalogram functional image, and the position and type configuration of the stimulation coil pair.

[0092] Use the following stimulation intensity acquisition formula to estimate the magnetic field intensity of a single magnetic stimulation coil pair in the target area. The stimulation intensity acquisition formula includes:

[0093] B = 0.5×μ 0 ×N×I×R 2 ×[R 2 +(d / 2 + x) 2 -（3 / 2） ;

[0094] μ 0 = 4×π×10 -7 Tm / A;

[0095] Wherein, N is the number of turns of the first coil, I is the coil current, R is the radius of the effective equivalent circular area of the first coil, x is the distance from the central symmetry point of the first coil to the center of the effective circle of the first coil, and d is the width of the first coil.

[0096] The magnetic field intensity of multiple magnetic stimulation coil pairs at the target focus is estimated using the isolation coupling principle. In one embodiment, the stimulation intensity acquisition formula further includes an attenuation correction coefficient η. The attenuation correction coefficient η is determined by the conductivity of the brain tissue between the magnetic stimulation coil and the target area and is related to the contrast ratio of gray matter and white matter in the brain tissue, and takes a value between 1.2 - 2.0.

[0097] ​The transcranial magnetic stimulation system disclosed in this application is determined based on the fMRI brain functional structure image and magnetoencephalogram functional image information near the target area. For a single magnetic stimulation coil, the estimated stimulation intensity on the cerebral cortex along the stimulation path between the coil and the target area shall not be stronger than 80% of the motor threshold to avoid adverse reactions such as headache, nausea, and even epilepsy. In step six, for the stimulation pulses of the same pair of magnetic stimulation coils, the pulse width is 200 us - 300 us, and the pulse interval is about 100 us, with the longest not exceeding 4000 us. The specific size is determined by the conductivity of the brain tissue between the magnetic stimulation coil and the target area and is related to the contrast ratio of gray matter and white matter in the brain tissue. In this invention, it is determined based on the fMRI brain functional structure image and magnetoencephalogram functional image information near the target area. In step seven, for different pairs of magnetic stimulation coils, the excitation timing is kept synchronous, or a continuous interval of 1 - 3 pulse periods and intervals is maintained. After all pairs of magnetic stimulation coils continuously send 20 pulses, they stop for a sum of 5 pulse periods and intervals and then start the excitation and sending of the next 20 continuous pulses. In one embodiment, the deep magnetic stimulation target area includes one of the following: frontal lobe, thalamus, cingulate gyrus, putamen, caudate nucleus, hippocampus, ventral striatum, and amygdala.

[0098] The transcranial magnetic stimulation system disclosed in this application adopts a precise and dexterous structural design to achieve precise magnetic stimulation of deep target areas in the brain and precise control of the magnetic stimulation intensity, enabling precise magnetic stimulation during the transcranial magnetic therapy process, greatly improving the effect of transcranial magnetic stimulation therapy, and being of great significance in the research of brain science and neuroscience.

[0099] Those skilled in the art can understand that all or part of the functions of the various methods in the above embodiments can be implemented in a hardware manner or in a computer program manner. When all or part of the functions in the above embodiments are implemented in a computer program manner, the program can be stored in a computer-readable storage medium. The storage medium can include: read-only memory, random access memory, magnetic disk, optical disk, hard disk, etc. The above functions are implemented by a computer executing the program. For example, the program is stored in the memory of the device, and when the processor executes the program in the memory, the above all or part of the functions can be implemented. In addition, when all or part of the functions in the above embodiments are implemented in a computer program manner, the program can also be stored in a storage medium such as a server, another computer, magnetic disk, optical disk, flash drive, or mobile hard disk, downloaded or copied and saved to the memory of the local device, or the system of the local device is updated. When the processor executes the program in the memory, the above all or part of the functions in the embodiments can be implemented.

[0100] The above uses specific examples to elaborate on the present invention, which is only used to help understand the present invention and is not intended to limit the present invention. For those skilled in the art to which the present invention pertains, based on the idea of the present invention, several simple deductions, deformations or substitutions can also be made.

Claims

1. A transcranial magnetic stimulation system, characterized in that, it includes: an image acquisition module for acquiring medical image data; the medical image data includes images of the target area to be magnetically stimulated inside the skull and images of the landmark area for target positioning; a model reconstruction module for three-dimensionally reconstructing the medical image data to obtain a virtual three-dimensional model; the virtual three-dimensional model includes the three-dimensional model of the target area after three-dimensional reconstruction of the target area, and the virtual three-dimensional model also includes the three-dimensional model of the landmark area after three-dimensional reconstruction of the landmark area; a positioning and fixing connection device for establishing a spatial positioning coordinate system and fixedly connecting the skull in the spatial positioning coordinate system; a target coordinate acquisition module for establishing a correspondence between the three-dimensional model of the landmark area in the virtual three-dimensional model and the landmark area in the spatial positioning coordinate system, and obtaining the coordinate value of the target area to be magnetically stimulated inside the skull in the spatial positioning coordinate system according to the spatial position relationship between the three-dimensional model of the landmark area and the three-dimensional model of the target area in the virtual three-dimensional model, and taking this coordinate value as the target coordinate; a magnetic stimulation device for fixedly connecting with the positioning and fixing connection device; the magnetic stimulation device includes a first electromagnetic generating coil group, the first electromagnetic generating coil group includes two first coils with the same structure, the two first coils are symmetrically arranged at the center on the positioning and fixing connection device, and the center of symmetry is located at the target coordinate; the two symmetrically arranged first coils of the first electromagnetic generating coil group form a pair of dual-focus magnetic stimulation coil pairs, emitting electromagnetic waves towards the center of symmetry to magnetically stimulate the target area; the positioning and fixing connection device includes a spherical fixing frame that can be disassembled into two identical hemispherical shapes, three circular guide rails are arranged on the spherical fixing frame, the circular planes where each circular guide rail is located are mutually at an angle of 60 degrees, and the center of each circular guide rail is located on the same straight line passing through the center point of the spherical fixing frame; the first electromagnetic generating coil group is fixedly connected to the positioning and fixing connection device through the circular guide rails.

2. The transcranial magnetic stimulation system according to claim 1, characterized in that, at least two coil fixing interfaces are arranged on each circular guide rail, and each coil fixing interface is evenly distributed on the circular guide rail, and the coil fixing interface is used for fixedly connecting the first coil and the circular guide rail.

3. The transcranial magnetic stimulation system according to claim 1, characterized in that, the magnetic stimulation device includes a second electromagnetic generating coil group, the second electromagnetic generating coil group includes two second coils with the same structure, the two second coils are symmetrically arranged at the center on the positioning and fixing connection device, and the center of symmetry is located at the target coordinate; the diameter of the second coil is smaller than that of the first coil; the two symmetrically arranged second coils of the second electromagnetic generating coil group form a pair of dual-focus magnetic stimulation coil pairs, emitting electromagnetic waves towards the center of symmetry to magnetically stimulate the target area.

4. The transcranial magnetic stimulation system according to claim 3, characterized in that, the shape of the first coil is oval, circular or "8"-shaped; and / or, the shape of the second coil is oval, circular or "8"-shaped.

5. The transcranial magnetic stimulation system according to claim 1, characterized in that, the magnetic stimulation device further comprises a stimulation driving control module, electrically connected to the first electromagnetic generating coil group; the magnetic stimulation device is used to perform timing control of the driving current on the two first coils or one of the first coils according to a preset coil stimulation intensity and stimulation timing.

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