CN116135252A - Device for magnetic stimulation of large animal nerves - Google Patents

Abstract

The invention discloses a device for magnetic nerve stimulation of a large animal, which comprises a fixed cage, wherein a coil track is sleeved on the periphery of the fixed cage, a coil winding is wound on the coil track, a signal controller transmits high-frequency pulse electric signals and transmits the high-frequency pulse electric signals to the coil winding through a signal wire, so that the coil winding generates a pulse magnetic field around the fixed cage and is used for stimulating the nerve regulation of the large animal, the pulse power of the whole machine can reach kilowatt level at the highest, and meanwhile, the circuit efficiency is further improved by adopting a resonant circuit. The invention solves the problems of low power and low efficiency of the annunciator in the electromagnetic stimulation device in the prior art, simultaneously solves the problem that the coil structure is arranged in the supporting sleeve and is inconvenient to adjust the coil, and simultaneously does not have a window for observing the activity condition of animals in the sleeve.

Description

Device for magnetic stimulation of large animal nerves

Technical Field

The invention relates to the technical field of magnetic nerve stimulation, in particular to a device for magnetic nerve stimulation of a large animal.

Background

The magnetic stimulation induces an induced electric field in the targeted tissue through a transient strong pulse magnetic field, so that the excitability of tissue neurons is changed, and the aims of noninvasive diagnosis and disease treatment are fulfilled. However, the long-time strong pulse magnetic field acts on the brain of a human body to easily induce side effects such as epilepsy, and the like, and has certain injury to the human body. Thus, the research on the specific mechanism of magnetic stimulation on nerves should be conducted first by studying the mechanism of action of magnetic stimulation on animal nerves similar to the physiological structure of human body.

Animals often have difficulty in matching in experiments, and injection anesthesia is generally adopted to achieve a complete braking effect. The nerve stimulation often requires long time and repeated experimental stimulation and imaging, and frequent high-dose anesthesia has an influence on the physiological state of large animals, and the influence on the nervous system is unknown, so that a device capable of fixing the animals for nerve magnetic stimulation is needed.

The utility model provides a chinese patent application for 201920994710.9 discloses a pulsed magnetic field support and be used for experimental animals's electromagnetic stimulation device, including coil structure, bearing structure and support sleeve, wherein coil structure sets up inside the support sleeve, and this kind of mode can carry out the magnetic stimulation experiment to animal nerve through coil structure, but the signal generator in the electromagnetic stimulation device takes place power less, efficiency is lower, and coil structure sets up in the support sleeve inside simultaneously, is inconvenient for adjusting the material of coil, winding length etc. and does not set up the window of observing animal activity condition in the sleeve simultaneously yet.

Disclosure of Invention

The invention aims to: the invention aims to provide a device for large animal neuromagnetic stimulation, which has a simple structure and is convenient for adjusting a coil to perform neuromagnetic stimulation in an animal awake state.

The technical scheme is as follows: in order to achieve the above purpose, the device for magnetic nerve stimulation of the large animal comprises a fixed cage, a coil track is sleeved on the periphery of the fixed cage, a coil winding is wound on the coil track, a signal controller comprises an AC/DC (alternating current/direct current) converter and a DC/AC (direct current/alternating current) converter, and the signal controller transmits high-frequency pulse electric signals to the coil winding through a signal wire so that the coil winding generates a pulse magnetic field around the fixed cage and is used for stimulating the regulating nerve of the large animal, wherein one end of the fixed cage is provided with an air valve for ventilating and observing the conditions in the cage.

The inner ring of the coil track is provided with a pulley block for the coil track to move upwards in the axial direction of the fixed cage.

Wherein, the outer ring of the coil track is carved with a groove for fixing the coil winding.

Wherein, the fixed cage, the coil winding and the coil track are all made of non-magnetic materials.

Wherein the coil winding is made of copper.

The section size of the copper wire is about 40mm, and the width of the wound winding along the axial direction of the fixing cage is 120-150 mm.

The beneficial effects are that: the invention has the following advantages: 1. the device generates an electromagnetic field by arranging the coil winding on the outer ring of the animal fixing cage, and directly carries out neuromagnetic stimulation in the awake state of the animal, and has simple structure and convenient operation;

2. the device adopts the non-magnetic material, is convenient for performing magnetic stimulation experiments in a magnetic resonance environment, and performs functional magnetic resonance imaging immediately after stimulation, thereby effectively capturing nerve activation and creating a larger space for the research of brain region functional connection;

3. the signal generator equipped with the device has high power and high efficiency, and can meet the nerve stimulation requirement of large animals.

Drawings

FIG. 1 is a schematic diagram of the structure of the device;

FIG. 2 is a schematic diagram of the magnetic field around the retaining cage;

fig. 3 is a schematic diagram of a coil track structure.

Detailed Description

The technical scheme of the present invention will be described in detail with reference to the following examples and the accompanying drawings.

As shown in fig. 1, the device for magnetic nerve stimulation of a large animal comprises a fixed cage 1, a coil track 2 is sleeved on the periphery of the fixed cage 1, a coil winding 3 is wound on the coil track 2, a signal controller 4 transmits high-frequency pulse electric signals to the coil winding 3 through a signal wire, and the coil winding 3 generates a pulse magnetic field around the fixed cage 1 for stimulating the regulating nerve of the large animal.

One end of the fixed cage 1 is provided with an air valve 11 for ventilation and observation of the conditions in the cage; the inner ring of the coil track 2 is provided with a pulley block for the coil track 2 to move axially on the fixing cage 1, and the outer ring of the coil track 2 is carved with a groove for fixing the coil winding 3.

The fixed cage 1, the coil winding 3 and the coil track 2 are all made of non-magnetic materials, so that a magnetic stimulation experiment is conveniently carried out in a magnetic resonance environment, functional magnetic resonance imaging is carried out immediately after stimulation, nerve activation is effectively captured, and a larger space is created for research of functional connection of brain regions. In this embodiment, the coil winding 3 is made of copper, the cross-sectional dimension of the copper wire is about 40mm, and the width of the wound winding along the axial direction of the fixing cage 1 is 120-150 mm.

The signal controller 4 is composed of a power electronic converter and mainly comprises an AC/DC alternating current-direct current converter and a DC/AC direct current-alternating current converter, wherein an AC/DC part is a direct current bus capacitor charging circuit, a bridge rectifier circuit is adopted, and SRC topology can be adopted to reduce the volume and the cost; the DC/AC part is a capacitor discharging circuit, and the energy stored by the DC bus capacitor is released through the LC resonance circuit to form a pulse signal. The input of the signal controller is power frequency alternating voltage, the output is high-frequency pulse voltage, and the highest power can reach kilowatt level. The AC/DC part consists of a MOSFET/IGBT, a resonance capacitor, a bus capacitor, a transformer and the like, and the DC/AC part consists of a diode, a resonance inductor, a capacitor, an IGBT/thyristor and the like, and the two parts are in a series structure. The resonant circuit can effectively improve circuit efficiency and reduce energy consumption.

In the embodiment, firstly, the size of a fixed cage is determined according to the body type of an animal; a cuboid shell with the wood, the processing periphery of which is 420mm wide and high, the length of which is 800mm and the thickness of which is 10mm is selected as the large animal fixing cage 1. One end of the short section of the fixed cage 1 is provided with an air valve 11, the air valve 11 is a plate structure with the length and the width of 420mm and the thickness of 30mm, and two ends of the air valve 11 are provided with tenons with the width of 8mm and the depth of 10mm, so that the air valve is conveniently fixed on the fixed cage 1, and air windows with the length of 240mm and the width of 40mm are uniformly distributed on the air valve 11.

Secondly, selecting proper coil windings 3 and coil tracks 2 according to the size of a fixed cage, using 160A, 3.33kHz and 14.8 turns of current as excitation sources, setting the coil material as copper, and simulating by using a Maxwell3D design module of AnsysElectronics Desktop2022R1 software, wherein the distribution of the magnetic field around the large animal fixed cage 1 is simulated, as shown in figure 3.

As shown in fig. 3, the coil track 2 has a square structure with an inner ring having a length and a width of 430mm, a height of 150mm and a thickness of 10mm, and the outer ring surface is engraved with a groove with a width of 10mm for fixing the coil winding 3. The pulley block is distributed in the coil track 2, the auxiliary coil winding 3 moves along the long axis direction of the fixed cage 1, and the coil winding 3 is formed by winding litz wire of which the thickness is 0.1mm by 400. In simulation software, a point is added at the center of the coil winding 3, and the magnetic induction intensity of the coil winding is 63.88mT, so that the requirement of the magnetic stimulation intensity of the nerve of a large animal is met.

During measurement, the valve 11 is opened, wooden base plates with proper sizes and quantity are paved in the fixing cage 1, the large animals are fixed in the cage, and the whole device is placed in the magnetic resonance equipment and accurately positioned. The coil track 2 is moved and fixed to the nerve section. The signal controller 4 is turned on, current flows to the coil winding 3 along the signal line, an instantaneous pulse magnetic field is generated in the surrounding space of the large animal, the magnetic field generates local induction current at the nerve of the large animal and activates the nerve, the signal controller 4 is turned off, functional magnetic resonance scanning is performed according to the imaging sequence of the determined magnetic resonance imaging equipment, and nerve activity of the nerve stimulating site is analyzed and evaluated.

In order to acquire the neural activity condition of the animal as soon as possible after the neural stimulation of the animal and ensure that the neural stimulation is effective and has no interference with the monitoring environment, the invention can be used for detecting the neural activity of the animal and the functional connection of each brain area. The device generates an electromagnetic field by arranging the coil winding on the outer ring of the animal fixing cage, and directly carries out neuromagnetic stimulation under the awake state of the animal, and has simple structure and convenient operation.

The device has high signal output power, can meet the requirement of nerve stimulation of large animals, can be placed in a magnetic resonance environment for use, can intervene by nerve imaging equipment when nerve stimulation is completed, can greatly shorten the time cost of nerve imaging, effectively captures nerve signals, and increases the accuracy and precision of nerve imaging.

Claims (6)

1. A device for magnetic stimulation of the nerve of large animals, comprising a fixation cage (1), characterized in that: the periphery of the fixed cage (1) is sleeved with a coil track (2), a coil winding (3) is wound on the coil track (2), the signal controller (4) comprises an AC/DC (alternating current/direct current) converter and a DC/AC (direct current/alternating current) converter, and transmits high-frequency pulse electric signals to the coil winding (3) through a signal wire, so that the coil winding (3) generates a pulse magnetic field around the fixed cage (1) for stimulating a regulating nerve of a large animal, and one end of the fixed cage (1) is provided with an air valve (11) for ventilating and observing conditions in the cage.

2. The device for magnetic stimulation of large animals according to claim 1, characterized in that: the inner ring of the coil track (2) is provided with a pulley block for the coil track (2) to move upwards in the axial direction of the fixed cage (1).

3. A device for magnetic nerve stimulation of large animals according to claim 3, characterized in that: the outer ring of the coil track (2) is carved with a groove for fixing the coil winding (3).

4. The device for magnetic stimulation of large animals according to claim 1, characterized in that: the fixing cage (1), the coil winding (3) and the coil track (2) are all made of non-magnetic materials.

5. The device for magnetic stimulation of large animals according to claim 4, wherein: the coil winding (3) is made of copper.

6. The device for magnetic stimulation of large animals according to claim 5, wherein: the section size of the copper wire is about 40mm, and the width of the wound winding along the axial direction of the fixing cage (1) is 120-150 mm.

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