CN117205444A - Transcranial magnetic folding coil, evaluation method thereof and computer equipment - Google Patents
Transcranial magnetic folding coil, evaluation method thereof and computer equipment Download PDFInfo
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Abstract
The application is suitable for the field of medical appliances, and provides a transcranial magnetic folding coil, an evaluation method thereof, a computer readable storage medium and computer equipment, wherein the transcranial magnetic folding coil comprises a transcranial magnetic coil with central symmetry, the transcranial magnetic coil is provided with a first coil and a second coil, the first coil is folded upwards along a folding chord of the first coil, the second coil is folded upwards along a folding chord of the second coil, the folding chords of the first coil and the second coil are parallel and equal, and the folding angles of the first coil and the second coil are equal; the circle center line of the connecting line of the first coil and the second coil is perpendicular to the folding chord of the first coil and the folding chord of the second coil respectively, the folding distance of the first coil is equal to the folding distance of the second coil, and the folding distance is the distance from the central symmetry point to the folding chord. The transcranial magnetic folding coil of the application greatly improves the focal power.
Description
Technical Field
The application belongs to the field of medical equipment, and particularly relates to a transcranial magnetic folding coil, an evaluation method thereof, a computer readable storage medium and computer equipment.
Background
Transcranial magnetic stimulation therapy is widely used in clinical practice as the only non-drug therapeutic treatment for neurological and psychiatric treatments. But even so, the focusing problem of transcranial magnetic therapy coils and the precise identification of the stimulation site remain significant challenges. The main problems are (1) that the coil designs existing on the market at present have excessive irrational property, the generated focal power is too low, and the problems of unnecessary stimulation generated by non-target tissues are not considered to be reduced; (2) The focusing performance of the current common general 8-shaped coil does not meet the stimulation requirement with higher precision, so a shielding plate with a holding window, which is made of high-conductivity materials, is arranged below the coil to improve the stimulation focusing power of the coil, but the method can cause eddy current phenomenon in the shielding plate, has resistance characteristic for the shielding plate, can generate a large amount of heat in the shielding plate, and the coil is electrified for a long time, so that the periphery of the coil is overheated and cannot approach the brain closely, thereby greatly reducing the stimulation efficiency of the coil.
Disclosure of Invention
The application aims to provide a transcranial magnetic folding coil, an evaluation method thereof, a computer readable storage medium and computer equipment, and aims to solve the problems that the existing transcranial magnetic coil is low in focusing degree and excessive in non-target stimulation.
In a first aspect, the application provides a transcranial magnetic folding coil, comprising a transcranial magnetic coil with central symmetry, wherein the transcranial magnetic coil is provided with a first coil and a second coil, the first coil is folded upwards along the folding chord of the first coil, the second coil is folded upwards along the folding chord of the second coil, the folding chord of the first coil and the folding chord of the second coil are parallel and equal, and the folding angles of the first coil and the second coil are equal; the circle center line of the connecting line of the first coil and the second coil is perpendicular to the folding chord of the first coil and the folding chord of the second coil respectively, the folding distance of the first coil is equal to the folding distance of the second coil, and the folding distance is the distance from the central symmetry point to the folding chord.
Further, the central symmetrical transcranial magnetic coil comprises a biconical coil and an 8-shaped coil.
Further, the current direction of the first coil is anticlockwise, and the current direction of the second coil is clockwise.
Further, the folding angle is an optimal folding angle obtained according to the changes of the electric field intensity, the focal power, the focusing area and the stimulation depth of the transcranial magnetic coil.
Further, the folding angle is an optimal folding angle obtained according to the changes of the electric field intensity, the focal power, the focusing area and the stimulation depth of the transcranial magnetic coil, and specifically comprises the following steps:
build up XZY coordinate system and X on transcranial magnetic folding coil 1 ′Y 1 ′Z 1 ' coordinate system, Y-axis and Y 1 The' axis passes through all circle centers of the transcranial magnetic coil, and the X axis and X 1 The' axis overlaps the folded chords of the first and second coils, respectively, the Z axis and Z 1 The' axis is perpendicular to the transcranial magnetic coil;
the preset folding angle is beta, and XZY coordinate system and X are the same when the transcranial magnetic coil is electrified 1 ′X 1 ′Z 1 The coordinate system respectively generates magnetic fields in different directions, the magnetic induction intensity B is subjected to vector decomposition along the X axis, the Y axis and the Z axis, and the component vectors of the X axis, the Y axis and the Z axis can be obtained through vector superposition;
selecting a point Q in a single turn coil on the folded surface of the first coil, setting the coordinate of the point Q in a XZY coordinate system as (x 1 ,y 1 ,z 1 ) Find X 1 ′Y 1 ′Z 1 The coordinates (x) of the Q 'point corresponding to the Q point in the' coordinate system 1 ′,y 1 ′,z 1 ' s), to yield:
find X 1 ′Y 1 ′Z 1 Component of magnetic induction B in three directions of X-axis, Y-axis and Z-axis under' coordinates: b (B) x4 ′，B y4 ′，B y4 Vector superposition is carried out, and the folded part is converted into an XYZ coordinate system, namely:
wherein N is the number of turns of the coil;
the pulse magnetic field generated by the transcranial magnetic folding coil induces an external electric field in the brain, the electric field is overlapped on two sides of a cell membrane to change the potential difference of the cell membrane, the induced electric field is generated by the time-varying magnetic field of the Maxwell equation set, and the induced electric field is deduced according to the size and distribution of the magnetic field; namely:
wherein,representing a gradient operator, wherein E is electric field intensity, B is magnetic induction intensity, r is vector diameter, t is time, and θ is bias guide;
when the folding distance is unchanged, the transcranial magnetic coil is folded upwards, and the optimal folding angle is obtained according to the changes of the electric field intensity, focal power, focusing area and stimulation depth of the transcranial magnetic coil.
In a second aspect, the present application provides a method for evaluating a transcranial magnetic folding coil, comprising:
obtaining the folding angle, the folding distance and the current of the transcranial magnetic folding coil;
obtaining the distribution condition of the intracranial electric field intensity according to the folding angle, the folding distance and the current;
obtaining the width of a focusing area with the electric field intensity larger than half the maximum electric field intensity according to the distribution condition of the electric field intensity, and obtaining a half-width area;
calculating the focusing area of the transcranial magnetic folding coil according to the distribution condition of the electric field intensity;
transcranial magnetic folding coils were evaluated based on half width area and focal area.
Further, the width of the focusing area with the electric field strength greater than half the maximum electric field strength is obtained according to the distribution condition of the electric field strength, so as to obtain a half-width area, which specifically includes:
obtaining the penetration capability of a transient magnetic field induced by the transcranial magnetic folding coil in the brain of a human according to the stimulation depth; the stimulation depth is the maximum electric field intensity E on the surface of the cortex layer max The electric field strength from the position to E max Longest distance d at/2 1/2 ；
The width area of the focusing area used for describing the induction electric field is half-width area HWR, and the induction electric field intensity E is more than or equal to E on the X axis max Distance/2 is defined as half width region HWR in the X-axis x The method comprises the steps of carrying out a first treatment on the surface of the The strength E of the induction electric field on the Y axis is more than or equal to E max The distance/2 is defined as half width region HWR on the Y-axis y 。
Further, the method calculates the focusing area of the transcranial magnetic folding coil according to the distribution condition of the electric field intensity, specifically comprises the following steps:
acquiring intracranial electric field strength E greater than E max Cumulative volume V of/2 1/2 ；
Obtaining the maximum electric field strength E max The electric field strength from the position to E max Longest distance d at/2 1/2 ；
According to the electric field intensity E being greater than E max Cumulative volume and longest distance d of/2 1/2 Calculate the focal area S 1/2 The method comprises the following steps:
wherein the focusing area S 1/2 Refers to the strength E of the induction electric field at the cortical layer being greater than E max Area of/2.
In a third aspect, the present application provides a computer readable storage medium storing a computer program which, when executed by a processor, implements the steps of the method of evaluating transcranial magnetic folding coils.
In a fourth aspect, the present application provides a computer device comprising: one or more processors, a memory, and one or more computer programs, the processors and the memory being connected by a bus, wherein the one or more computer programs are stored in the memory and configured to be executed by the one or more processors, which when executing the computer programs implement the steps of the method of evaluating transcranial magnetic folding coils.
In the application, after the transcranial magnetic coil is folded, the focusing area of the coil is reduced, the focusing degree is greatly improved, and unnecessary stimulation generated by non-target cell tissues is reduced; an evaluation system for evaluating the focusing power of the transcranial magnetic folding coil by combining the three-dimensional evaluation focusing area and the two-dimensional plane half-width area is designed, can be used for evaluating an induction electric field generated in the cranium, and provides a basis for the design of a treatment scheme for improving the focusing precision in the later period.
Drawings
Fig. 1 is a block diagram of a transcranial magnetic folding coil provided in an embodiment of the present application.
Fig. 2 is a spatial coordinate diagram of a transcranial magnetic folding coil provided by an embodiment of the present application.
Fig. 3 is a method of evaluating a transcranial magnetic folding coil according to another embodiment of the present application.
FIG. 4 is a table of data for the impact of angle change on the evaluation system provided by another embodiment of the present application.
Fig. 5 is a block diagram of a computer device according to another embodiment of the present application.
Detailed Description
In order to make the objects, technical solutions and advantageous effects of the present application more apparent, the present application will be further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.
In order to illustrate the technical scheme of the application, the following description is made by specific examples.
Referring to fig. 1, an embodiment of the present application provides a transcranial magnetic folding coil, including a transcranial magnetic coil with central symmetry, wherein the transcranial magnetic coil is provided with a first coil 001 and a second coil 002, the first coil 001 is folded upwards along a folding chord 003 of the first coil 001, the second coil 002 is folded upwards along a folding chord 003 of the second coil 002, the folding chords 003 and 003 of the first coil 001 and the second coil 002 are parallel and equal, and folding angles of the first coil 001 and the second coil 002 are equal; the center line of the connecting line of the first coil 001 and the second coil 002 is perpendicular to the folding string 003 of the first coil 001 and the folding string 003 of the second coil 002 respectively, the folding distance 004 of the first coil 001 is equal to the folding distance 005 of the second coil 002, and the folding distance is the distance from the central symmetry point to the folding string.
Referring to fig. 2, the folded coil is divided into four parts 1, 2, 3 and 4.
The folding distance is 2 or 3 parts.
In one embodiment of the application, the centrally symmetric transcranial magnetic coil comprises a biconic coil and a figure 8 coil.
In an embodiment of the present application, a current direction of the first coil is counterclockwise, and a current direction of the second coil is clockwise.
In one embodiment of the present application, the folding angle is an optimal folding angle obtained according to the changes of the electric field intensity, focal power, focal area and stimulation depth of the transcranial magnetic coil.
In an embodiment of the present application, the folding angle is an optimal folding angle obtained according to the changes of the electric field intensity, focal power, focal area and stimulation depth of the transcranial magnetic coil, and specifically is:
build up XZY coordinate system and X on transcranial magnetic folding coil 1 ′Y 1 ′Z 1 ' coordinate system, Y-axis and Y 1 The' axis passes through all circle centers of the transcranial magnetic coil, and the X axis and X 1 The' axis overlaps the folded chords of the first and second coils, respectively, the Z axis and Z 1 The' axis is perpendicular to the transcranial magnetic coil;
the preset folding angle is beta, and XZY coordinate system and X are the same when the transcranial magnetic coil is electrified 1 ′Y 1 ′Z 1 The coordinate system respectively generates magnetic fields in different directions, the magnetic induction intensity B is subjected to vector decomposition along the X axis, the Y axis and the Z axis, and the component vectors of the X axis, the Y axis and the Z axis can be obtained through vector superposition;
selecting a point Q in a single turn coil on the folded surface of the first coil, setting the coordinate of the point Q in a XZY coordinate system as (x 1 ,y 1 ,z 1 ) Find X 1 ′Y 1 ′Z 1 The coordinates (x) of the Q 'point corresponding to the Q point in the' coordinate system 1 ′,y 1 ′,z 1 ' s), to yield:
find X 1 ′Y 1 ′Z 1 Component of magnetic induction B in three directions of X-axis, Y-axis and Z-axis under' coordinates: b (B) x4 ′，B y4 ′，B y4 Vector superposition is carried out, and the folded part is converted into an XYZ coordinate system, namely:
wherein N is the number of turns of the coil;
the pulse magnetic field generated by the transcranial magnetic folding coil induces an external electric field in the brain, the electric field is overlapped on two sides of a cell membrane to change the potential difference of the cell membrane, the induced electric field is generated by the time-varying magnetic field of the Maxwell equation set, and the induced electric field is deduced according to the size and distribution of the magnetic field; namely:
wherein,representing a gradient operator, wherein E is electric field intensity, B is magnetic induction intensity, r is vector diameter, t is time, and θ is bias guide;
when the folding distance is unchanged, the transcranial magnetic coil is folded upwards, and the optimal folding angle is obtained according to the changes of the electric field intensity, focal power, focusing area and stimulation depth of the transcranial magnetic coil.
In the embodiment of the application, after the transcranial magnetic coil is folded, the focusing area of the coil is reduced, the focusing degree is greatly improved, and unnecessary stimulation generated by non-target cell tissues is reduced.
Referring to fig. 3, another embodiment of the application provides an evaluation method of a transcranial magnetic folding coil, comprising the following steps: it should be noted that, if the results are substantially the same, the evaluation method of the transcranial magnetic folding coil according to the present application is not limited to the flow sequence shown in fig. 3.
S101, acquiring a folding angle, a folding distance and current of a transcranial magnetic folding coil;
s102, obtaining distribution conditions of intracranial electric field intensity according to the folding angle, the folding distance and the current;
s103, obtaining the width of a focusing area with the electric field intensity larger than half maximum electric field intensity according to the distribution condition of the electric field intensity, and obtaining a half-width area;
s104, calculating the focusing area of the transcranial magnetic folding coil according to the distribution condition of the electric field intensity;
s105, evaluating the transcranial magnetic folding coil according to the half-width area and the focusing area.
The half-width area is the width of a focusing section of a real electric field on a two-dimensional plane, can truly reflect the focusing condition of the real electric field, and is easily influenced by the depth of a target area; the focusing area is the aggregation of the macroscopic coils and represents a three-dimensional evaluation index. The smaller the half-width area, the better the transcranial magnetic folding coil effect according to the smaller the focal area.
In another embodiment of the present application, the width of the focusing area with the electric field strength greater than half the maximum electric field strength is obtained according to the distribution of the electric field strength, so as to obtain a half-width area, which specifically is:
obtaining the penetration capability of a transient magnetic field induced by the transcranial magnetic folding coil in the brain of a human according to the stimulation depth; the stimulation depth is the maximum electric field intensity E on the surface of the cortex layer max The electric field strength from the position to E max Longest distance d at/2 1/2 ；
The width area of the focusing area used for describing the induction electric field is half-width area HWR, and the induction electric field intensity E is more than or equal to E on the X axis max Distance/2 is defined as half width region HWR in the X-axis x The method comprises the steps of carrying out a first treatment on the surface of the The strength E of the induction electric field on the Y axis is more than or equal to E max The distance/2 is defined as half width region HWR on the Y-axis y 。
In another embodiment of the present application, the calculating the focusing area of the transcranial magnetic folding coil according to the distribution of the electric field intensity specifically includes:
acquiring intracranial electric field strength E greater than E max Cumulative volume V of/2 1/2 ；
Obtaining the maximum electric field strength E max The electric field strength from the position to E max Longest distance d at/2 1/2 ；
According to the electric field intensity E being greater than E max Cumulative volume and longest distance d of/2 1/2 Calculate the focal area S 1/2 The method comprises the following steps:
wherein the focusing area S 1/2 Refers to the strength E of the induction electric field at the cortical layer being greater than E max Area of/2.
Taking a folded coil of a 8-shaped coil as an example:
in order to obtain the optimal folding angle, the folding angle range of the two sides of the coil is set to be 0-90 degrees, and the folding distance is 56mm of the radius of the largest coil. The electric field intensity of the brain model is reduced layer by layer along with the increase of the depth, the two sides of the coil are folded upwards to influence the induction electric field received by the surface of the model, and the electric field change of the seven-layer model is in a descending trend along with the increase of the angle; in addition, the skin layer closest to the coil is not the seven largest electric fields, but the gray layer deep in the model, and the maximum of the electric field strength of the cortical layer is related not only to the linear distance of the surface to the coil, but also to its physical properties (conductivity, dielectric constant, etc.). In addition, the overall surface electric field strength of the model is the result of superposition of seven tissues, and the trend of the gray layer is very close to the maximum surface electric field, which means that the electric field value of the gray layer greatly influences the overall surface electric field strength value and determines the trend of the overall electric field strength.
FIG. 4 is a data table of the effect of angle change on the evaluation system; the application evaluates the folding coil on the electric field focusing in the aspects of focusing degree and half-width area, and compared with the 8-shaped coil, the focusing area of the folding coil is reduced by the cliff, which shows that the folding coil has absolute advantage on focusing degree. The results show that 9.161 ×10 is reached at a folding angle of 90 deg -5 m 2 For the best coil, but we also found that the stimulation depth and the electric field strength at 90 ° were experimentally the smallest, reaching 8.551mm and 192.751V/m, respectively, which did not meet the best coil design criteria, and therefore, from a practical point of view, the electric field widths generated in the model cut planes were compared. HWR at 30 DEG X 10.401mm HWR Y Is 2.744mm compared with a 8-shaped coil HWR X 11.17% lower HWR Y Reduced by 28.08%; HWR at 90 DEG X 10.665mm HWR Y 2.515mm compared with 8-shaped coil HWR X Reduced by 8.91%, HWR Y Reduced by 34.41%; both exhibit an optimum in different directions; but the surface maximum field intensity index of the folded 30-degree coil is obviously higher than that of the folded 90-degree coil by 27.12 percent; in addition, the coil depth of the coil folded by 30 degrees is 9.129mm on the depth index, which is 8.91 percent higher than that of the coil folded by 90 degrees.
When the angle of the folding coil is larger than 90 degrees, the folding part can generate serious interference on the field intensity, so that the field intensity value is greatly reduced, and the intervention effect of TMS is influenced. Therefore, the angle of the folding coil is limited to the range of 0 to 90 degrees, and the situation when the angle is larger than 90 degrees is not considered in the folding distance change simulation experiment.
An embodiment of the present application provides a computer-readable storage medium storing a computer program which, when executed by a processor, implements the steps of the evaluation method of a transcranial magnetic folding coil as provided by an embodiment of the present application.
Fig. 5 shows a specific block diagram of a computer device according to an embodiment of the present application, where a computer device 100 includes: one or more processors 101, a memory 102, and one or more computer programs, wherein the processors 101 and the memory 102 are connected by a bus, the one or more computer programs being stored in the memory 102 and configured to be executed by the one or more processors 101, the processor 101 implementing the steps of the method for evaluating a transcranial magnetic folding coil as provided by an embodiment of the present application when the computer programs are executed.
The computer device includes a server, a terminal, and the like. The computer device may be a desktop computer, a mobile terminal or a vehicle-mounted device, the mobile terminal including at least one of a cell phone, a tablet computer, a personal digital assistant or a wearable device, etc.
In the embodiment of the application, an evaluation system for evaluating the focusing power of the transcranial magnetic folding coil by combining the three-dimensional evaluation focusing area and the two-dimensional plane half-width area is designed, and the evaluation system can be used for evaluating an induction electric field generated in the cranium and provides a basis for the design of a treatment scheme for improving the focusing precision in the later stage.
Those of ordinary skill in the art will appreciate that all or part of the steps in the various methods of the above embodiments may be implemented by a program to instruct related hardware, the program may be stored in a computer readable storage medium, and the storage medium may include: read Only Memory (ROM), random access Memory (RAM, random Access Memory), magnetic or optical disk, and the like.
The foregoing description of the preferred embodiments of the application is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the application.
Claims (10)
1. The transcranial magnetic folding coil is characterized by comprising a transcranial magnetic coil with central symmetry, wherein the transcranial magnetic coil is provided with a first coil and a second coil, the first coil is folded upwards along the folding chord of the first coil, the second coil is folded upwards along the folding chord of the second coil, the folding chord of the first coil and the folding chord of the second coil are parallel and equal, and the folding angles of the first coil and the second coil are equal; the circle center line of the connecting line of the first coil and the second coil is perpendicular to the folding chord of the first coil and the folding chord of the second coil respectively, the folding distance of the first coil is equal to the folding distance of the second coil, and the folding distance is the distance from the central symmetry point to the folding chord.
2. The transcranial magnetic folding coil of claim 1 wherein the centrally symmetric transcranial magnetic coil includes a biconic coil and a figure 8 coil.
3. The transcranial magnetic folding coil of claim 1 wherein the direction of current flow of the first coil is counter-clockwise and the direction of current flow of the second coil is clockwise.
4. The transcranial magnetic folding coil of claim 1, wherein the folding angle is an optimal folding angle obtained from variations in electric field strength, focal power, focal area, and stimulation depth of the transcranial magnetic coil.
5. The transcranial magnetic folding coil according to claim 4, wherein the folding angle is an optimal folding angle obtained according to the changes of electric field intensity, focal power, focal area and stimulation depth of the transcranial magnetic coil, specifically:
build up XZY coordinate system and X on transcranial magnetic folding coil 1 ′Y 1 ′Z 1 ' coordinate system, Y-axis and Y 1 The' axis passes through all circle centers of the transcranial magnetic coil, and the X axis and X 1 The' axis overlaps the folded chords of the first and second coils, respectively, the Z axis and Z 1 The' axis is perpendicular to the transcranial magnetic coil;
the preset folding angle is beta, and XZY coordinate system and X are the same when the transcranial magnetic coil is electrified 1 ′Y 1 ′Z 1 The coordinate system respectively generates magnetic fields in different directions, the magnetic induction intensity B is subjected to vector decomposition along the X axis, the Y axis and the Z axis, and the component vectors of the X axis, the Y axis and the Z axis can be obtained through vector superposition;
selecting a point Q in a single turn coil on the folded surface of the first coil, setting the coordinate of the point Q in a XZY coordinate system as (x 1 ,y 1 ,z 1 ) Find X 1 ′Y 1 ′Z 1 The coordinates (x) of the Q 'point corresponding to the Q point in the' coordinate system 1 ′,y 1 ′,z 1 ' s), to yield:
find X 1 ′Y 1 ′Z 1 Component of magnetic induction B in three directions of X-axis, Y-axis and Z-axis under' coordinates: b (B) x4 ′，B y4 ′，B y4 Vector superposition is carried out, and the folded part is converted into an XYZ coordinate system, namely:
wherein N is the number of turns of the coil;
the pulse magnetic field generated by the transcranial magnetic folding coil induces an external electric field in the brain, the electric field is overlapped on two sides of a cell membrane to change the potential difference of the cell membrane, the induced electric field is generated by the time-varying magnetic field of the Maxwell equation set, and the induced electric field is deduced according to the size and distribution of the magnetic field; namely:
wherein,representing a gradient operator, E is the electric field intensity, B is the magnetic induction intensity, r is the vector diameter, t is the time,/and B is the magnetic induction intensity>Is a deflection guide;
when the folding distance is unchanged, the transcranial magnetic coil is folded upwards, and the optimal folding angle is obtained according to the changes of the electric field intensity, focal power, focusing area and stimulation depth of the transcranial magnetic coil.
6. A method of evaluating a transcranial magnetic folding coil, comprising:
obtaining the folding angle, the folding distance and the current of the transcranial magnetic folding coil;
obtaining the distribution condition of the intracranial electric field intensity according to the folding angle, the folding distance and the current;
obtaining the width of a focusing area with the electric field intensity larger than half the maximum electric field intensity according to the distribution condition of the electric field intensity, and obtaining a half-width area;
calculating the focusing area of the transcranial magnetic folding coil according to the distribution condition of the electric field intensity;
transcranial magnetic folding coils were evaluated based on half width area and focal area.
7. The method of claim 6, wherein the step of obtaining the width of the focusing region having an electric field strength greater than half the maximum electric field strength according to the distribution of the electric field strength, to obtain the half-width region, comprises:
obtaining the penetration capability of a transient magnetic field induced by the transcranial magnetic folding coil in the brain of a human according to the stimulation depth; the stimulation depth is the maximum electric field intensity E on the surface of the cortex layer max The electric field strength from the position to E max Longest distance d at/2 1/2 ；
The width area of the focusing area used for describing the induction electric field is half-width area HWR, and the induction electric field intensity E is more than or equal to E on the X axis max Distance/2 is defined as half width region HWR in the X-axis x The method comprises the steps of carrying out a first treatment on the surface of the The strength E of the induction electric field on the Y axis is more than or equal to E max The distance/2 is defined as half width region HWR on the Y-axis y 。
8. The evaluation method according to claim 6, wherein the calculation of the focusing area of the transcranial magnetic folding coil according to the distribution of the electric field intensity is specifically:
acquiring intracranial electric field strength E greater than E max Cumulative volume V of/2 1/2 ；
Obtaining the maximum electric field strength E max The electric field strength from the position to E max Longest distance d at/2 1/2 ；
According to the electric field intensity E being greater than E max Cumulative volume and longest distance d of/2 1/2 Calculate the focal area S 1/2 The method comprises the following steps:
wherein the focusing area S 1/2 Refers to the strength E of the induction electric field at the cortical layer being greater than E max Area of/2.
9. A computer-readable storage medium storing a computer program, characterized in that the computer program, when executed by a processor, implements the steps of the evaluation method of a transcranial magnetic folding coil according to any one of claims 6 to 8.
10. A computer device, comprising:
one or more processors;
a memory; and
one or more computer programs, the processor and the memory being connected by a bus, wherein the one or more computer programs are stored in the memory and configured to be executed by the one or more processors, characterized in that the processor, when executing the computer programs, implements the steps of the method of evaluating a transcranial magnetic folding coil according to any one of claims 6 to 8.
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