Target animal fixing device

Abstract

The target animal fixing device comprises a base, a head fixing assembly and a lower jaw fixing assembly, and the head fixing assembly is arranged on one side of the base; the lower jaw fixing assembly is arranged on one side of the base, the lower jaw fixing assembly is provided with a bearing face used for bearing the lower jaw of the target animal, and the lower jaw fixing assembly is configured to be capable of adjusting the height of the bearing face relative to the base so as to adaptively underlay the lower jaw of the target animal. The base provides a stable installation foundation for the head fixing assembly and the lower jaw fixing assembly, the lower jaw supporting requirements of mice of different development stages and different body types are met, motion artifacts generated by lower jaw micro motion are reduced, meanwhile, the head fixing assembly is matched for fixing the head of the mice, the signal-to-noise ratio and the spatial resolution of MRI imaging are remarkably improved, and the MRI imaging quality is improved. And the accuracy of experimental data is ensured.

Description

Technical Field

[0001] This application relates to the fields of animal experimental devices and in vivo imaging technology, and in particular to a target animal restraint device. Background Technology

[0002] In studies of brain function and neural circuit mechanisms, magnetic resonance imaging (MRI) of awake mice is of great significance. Compared with imaging under anesthesia, the functional state of awake animals is closer to their physiological reality, but it places higher demands on the stability and comfort of the subject's head. To obtain images with high signal-to-noise ratio and low artifacts, while preserving the animal's natural behavior as much as possible, reliable and repeatable fixation of the mouse head is required, and the fixation structure must be compatible with specific MRI detection platforms.

[0003] Traditional head immobilization devices for small animal MRI primarily employ surgically implanted head frames for head restraint, such as horizontal bars or large external supports. These methods have drawbacks: First, the implanted head frame may restrict or interfere with certain behavioral tasks; second, snap-fit ​​fixation structures often require forceful disassembly during installation or removal, potentially causing soft tissue compression or head frame detachment, increasing stress and injury risks; finally, traditional fixation devices often use a single-size or fixed head frame structure, making it difficult to adapt to mice at different developmental stages and of different sizes, resulting in unstable fixation or discomfort due to pressure. This can lead to micro-movements of the head during scanning, causing motion artifacts in the MRI images and severely affecting image quality. Summary of the Invention

[0004] To solve at least one of the above-mentioned technical problems, this application provides a target animal restraint device, and the technical solution adopted is as follows.

[0005] The target animal restraint device provided in this application is used to restrain an conscious target animal, and the target animal restraint device includes: Base; A head fixing assembly is disposed on the base; A mandibular fixation assembly is disposed on the base, the mandibular fixation assembly having a support surface for supporting the mandible of the target animal, the mandibular fixation assembly being configured to adjust the height of the support surface relative to the base to adaptively pad the mandible of the target animal.

[0006] In some embodiments of this application, the chin fixation assembly includes a pad, a first connecting portion, and a locking structure. The first connecting portion is disposed on the base, the pad is slidably connected to the first connecting portion to move closer to or further away from the base, and the locking structure is used to lock the pad at a target height.

[0007] In some embodiments of this application, the mandibular fixation assembly includes pads of various thicknesses, which are detachably connected to the base.

[0008] In some embodiments of this application, the pad includes a base, a first sidewall, and a second sidewall, the first sidewall and the second sidewall being respectively connected to both sides of the base, and the first sidewall and the second sidewall being disposed on both sides of the base along its length.

[0009] In some embodiments of this application, the head fixing assembly includes a second connecting portion and a head frame, the second connecting portion being connected to the base, and the head frame being detachably connected to the second connecting portion.

[0010] In some embodiments of this application, the head fixing component is movably connected to the base so that the head fixing component can move along the width direction of the base.

[0011] In some embodiments of this application, the head frame has a protrusion on the side away from the base, the protrusion being used to fit against the top of the target animal's head.

[0012] In some embodiments of this application, the head fixation assembly includes the head frame in various sizes.

[0013] In some embodiments of this application, a pair of body fixing plates are provided on one side of the base, and the body fixing plates are arranged along the length direction of the base.

[0014] In some embodiments of this application, the base is provided with a third connecting portion for connecting the target animal fixation device to the MRI bed.

[0015] This application has at least the following beneficial effects: The base provides a stable mounting foundation for the head fixation component and the mandibular fixation component. The three components work together to achieve dual fixation of the target animal's head and mandible, avoiding head or mandibular displacement caused by struggling in awake target animals and ensuring the stability of the target animal's position during scanning. The mandibular fixation component can achieve height adaptation between the contact area of ​​the target animal's mandible and the base through its own structure. It can meet the mandibular support needs of target animals at different developmental stages and of different body sizes without replacing the entire device, avoiding problems of unstable fixation or insufficient support due to differences in the size of the target animal. The device has strong versatility. The mandibular fixation component can accurately fit the target animal's mandible and provide stable support, effectively limiting mandibular movement in awake target animals during scanning, reducing motion artifacts caused by mandibular micro-movements. At the same time, in conjunction with the fixation effect of the head fixation component on the target animal's head, it significantly improves the signal-to-noise ratio and spatial resolution of MRI imaging and ensures the accuracy of experimental data.

[0016] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0017] The present application will be further illustrated below with reference to the accompanying drawings and embodiments. It should be noted that the embodiments illustrated in the following drawings are exemplary and are only used to explain the present application, and should not be construed as limiting the present application.

[0018] Figure 1 This is a schematic diagram of a target animal restraint device in one embodiment of this application; Figure 2 This is a schematic diagram of the base of the target animal restraint device in one embodiment of this application; Figure 3 for Figure 2 Top view; Figure 4 This is a schematic diagram of a pad block in one embodiment of this application; Figure 5 This is a schematic diagram of the head frame in one embodiment of this application.

[0019] Reference numeral: Base 100; Head fixing assembly 200; head frame 210; protrusion 211; first mounting hole 212; second connecting part 220; second mounting hole 221; guide rail 230; Jaw fixation assembly 300; pad 310; mounting part 311; base 312; first sidewall 313; second sidewall 314; first pad layer 315; first connecting hole 316; first connecting part 320; second connecting hole 321; Body fixation plate 400; second padding layer 410; Third connecting part 500; third mounting hole 510. Detailed Implementation

[0020] The following is combined with Figures 1 to 5 The embodiments of this application are described in detail below, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0021] In the description of this application, it should be understood that the terms "center", "middle", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0022] In the description of this application, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0023] In the description of this application, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0024] In the description of this application, the use of terms such as "one embodiment," "some embodiments," "an example," "some instances," "some embodiments," "illustrative embodiment," "example," "specific example," and "some examples" indicates that the specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0025] In this application, the target animal is a mouse, but it is not limited to mice.

[0026] Magnetic resonance imaging (MRI) can reveal structural and functional information within organisms in a non-invasive manner. To elucidate brain function and neural circuit mechanisms, this application designs a target animal fixation device based on a research mouse model. Compared to imaging under anesthesia, the functional state of awake animals is closer to their physiological reality. To obtain images with high signal-to-noise ratio and low artifacts, while preserving the animal's natural behavioral state as much as possible, reliable and repeatable fixation of the mouse head is required, and the fixation structure must be compatible with specific MRI detection platforms. Therefore, the target animal fixation device of this application was designed.

[0027] All structural components of the target animal restraint device are made of non-magnetic, high-strength, lightweight materials.

[0028] Combination Figure 1 and Figure 3 As shown, the target animal restraint device provided in this application includes: Base 100; A head fixing component 200 is disposed on one side of the base 100; The mandibular fixation component 300 is disposed on one side of the base 100. The mandibular fixation component 300 is capable of having a support surface for supporting the mouse's mandible. The mandibular fixation component 300 is configured to adjust the height of the support surface relative to the base 100 to adaptively support the mouse's mandible.

[0029] The base 100 is a long strip or rectangular flat plate structure, placed horizontally, with the x-direction being the length direction of the base 100 and the y-direction being the width direction. The head fixation component 200 and the mandible fixation component 300 are both mounted on the base 100, specifically on its upper side. The head fixation component 200 and the mandible fixation component 300 are spaced apart along the length of the base 100, with the spacing determined based on the physiological positional relationship between the head and mandible of a typical experimental mouse. This arrangement secures the mouse's head and mandible respectively, facilitating a close fit to the mouse's physiological structure.

[0030] The head fixation component 200 is located on one side of the base 100. It can be fixed to the upper surface of the base 100 by welding, integral molding, or detachable connection. Its specific structure can be designed as an arc-shaped plate, frame, etc., depending on the mouse's head fixation requirements. Its core function is to limit and fix the mouse's head, preventing significant left-right or up-down movement. The head fixation component 200 is made of the same material as the base 100 to ensure no magnetic interference, and its size design conforms to the overall contour of a typical laboratory mouse's head, ensuring a close fit.

[0031] The mandibular fixation component 300 is also located on one side of the base 100, corresponding to the head fixation component 200, and is used to support the mouse's mandible. The mandibular fixation component 300 can have a support surface for supporting the mouse's mandible, and the mandibular fixation component 300 is configured to adjust the height of the support surface relative to the base 100. For example, the mandibular fixation component 300 can be designed with multiple structures of different heights or be designed to adjust its height relative to the base 100 to adaptively match contact with the mouse's mandible.

[0032] In use, first place an awake mouse on the base 100, so that the mouse's head fits against the head fixation component 200. Then, adjust the height of the contact part by adjusting the structure of the mandibular fixation component 300 to make it fit precisely against the bottom of the mouse's mandible and provide stable support, thus completing the fixation of the mouse's head and mandible. After that, the device can be connected to the MRI bed for scanning experiments.

[0033] All structural components of the target animal fixation device are made of non-magnetic, high-strength, lightweight materials, such as polyetheretherketone (PEEK) and nylon, to ensure electromagnetic compatibility with the high-field MRI environment and avoid magnetization artifacts.

[0034] The base 100 provides a stable mounting foundation for the head fixation component 200 and the mandibular fixation component 300. The three components work together to fix the mouse's head and mandible, preventing head or mandibular displacement caused by struggling in awake mice and ensuring the stability of the mouse's position during scanning. The mandibular fixation component 300 can achieve height adaptation between the contact area of ​​the mouse's mandible and the base through its own structure. It can meet the mandibular support needs of mice at different developmental stages and of different sizes without replacing the entire device, avoiding problems of unstable fixation or insufficient support due to differences in mouse size. The device has strong versatility. The mandibular fixation component 300 can precisely fit the mouse's mandible and provide stable support, effectively limiting mandibular movement in awake mice during scanning and reducing motion artifacts caused by mandibular micro-movements. At the same time, in conjunction with the fixation effect of the head fixation component 200 on the mouse's head, it significantly improves the signal-to-noise ratio and spatial resolution of MRI imaging and ensures the accuracy of experimental data.

[0035] In some embodiments, the chin fixation assembly 300 includes a pad 310, a first connecting portion 320, and a locking structure. The first connecting portion 320 is disposed on one side of the base 100. The pad 310 is slidably connected to the first connecting portion 320 to move closer to or further away from the base 100, adjusting its height relative to the base 100. The locking structure is used to lock the pad 310 at a target height. It is understood that the first connecting portion 320 is one or two plate-like structures disposed on the base 100, and the pad 310 and the first connecting portion 320 are fitted with a shaft hole. A slotted hole can be provided in the first connecting portion 320, and the pad 310 can be designed with a shaft or a bolt. The bolt passes through the slotted hole and a nut is installed to adjust the height. Alternatively, a hole can be designed on the pad 310, and the first connecting portion 320 extends out through the through-hole shaft structure. The shaft, bolt, and nut are all made of non-magnetic, high-strength, lightweight materials.

[0036] Specifically, the pad 310 has first connecting holes 316 on both sides for shafts or bolts to pass through; the first connecting part 320 consists of two ear plates perpendicular to the base 100, and the two first connecting parts 320 are symmetrically arranged along the axis of the base 100, with second connecting holes 321 on the ear plates. The first connecting hole 316 is a round hole, through which a shaft or bolt passes simultaneously. Each side of the pad 310 has a shaft or bolt inserted into its first connecting hole 316, and can be fixed or loosened by threaded nuts to the bolts, thereby adjusting the height of the pad 310. Through the sliding connection structure, the pad 310 can move smoothly along the second connecting hole 321 of the first connecting part 320, and with the locking element, achieves precise height positioning, adapting to the height differences of different mouse mandibles, and providing more precise support.

[0037] Alternatively, the mandibular fixation component 300 includes pads 310 of various thicknesses, which are detachably connected to the base 100. The pads 310 of different heights are designed based on common body size differences in experimental mice, ensuring coverage of the mandibular height requirements of mice at different developmental stages, such as juveniles and adults. Researchers can select the pad 310 of the appropriate height based on the specific body size of the mouse to be fixed, and quickly assemble it with the base 100 via the connecting structure to complete the installation of the mandibular fixation component 300. When it is necessary to change mice of different body sizes for experiments, simply remove the current pad 310 and replace it with a pad 310 of the corresponding thickness. This allows for targeted adaptation to mice with different mandibular heights without complex modifications to the device, meeting diverse experimental needs.

[0038] Combination Figure 4As shown, in some embodiments, the pad 310 includes a base 312, a first sidewall 313, and a second sidewall 314. The first sidewall 313 and the second sidewall 314 are respectively connected to both sides of the base 312, and are disposed on both sides of the base 100 along its length. The pad 310 is made of a non-magnetic, high-strength material with a certain degree of flexibility, such as polyetheretherketone (PEEK) or nylon, and is integrally formed or assembled from the base 312, the first sidewall 313, and the second sidewall 314. It can be understood that the base 312, the first sidewall 313, and the second sidewall 314 form a U-shaped structure, with the first sidewall 313 and the second sidewall 314 located on the left and right sides of the mouse's mandible, respectively. The distance between the first sidewall 313 and the second sidewall 314 is designed according to the width of the mandible of a typical laboratory mouse, so as not to compress the sides of the mandible, while leaving a slight space for movement to balance comfort and stability, avoid stress response in mice caused by local pressure concentration, and improve the comfort of the fixation process. The pad 310 fits snugly against the mouse's mandible, effectively preventing the head from shaking up and down during scanning, and further reducing functional imaging artifacts caused by mandibular movement.

[0039] Specifically, the base 312, the first sidewall 313, and the second sidewall 314 of the pad 310 are disposed on the mounting part 311. The mounting part 311 is a block structure, and first connecting holes 316 are provided on both sides of the mounting part 311.

[0040] Specifically, the inner wall formed by the base 312, the first sidewall 313, and the second sidewall 314 has a smooth transition structure. The inner wall is covered with a soft, non-slip pad layer, namely the first pad layer 315, such as medical silicone, to prevent scratching the soft tissue of the mouse's jaw or causing pressure stress, thereby further improving the comfort of the fixation process. The inner side of the first pad layer 315 away from the base 100 is the support surface.

[0041] Combination Figure 1 , Figure 2 , Figure 5 As shown, in some embodiments, the head fixation assembly 200 includes a second connecting portion 220 and a head frame 210. The second connecting portion 220 is connected to the base 100, and the head frame 210 is detachably connected to the second connecting portion 220. The second connecting portion 220 is a protruding structure or frame structure fixed to the upper surface of the base 100, and its material is the same as that of the base 100, which is a non-magnetic material. The head frame 210 is an arc-shaped structure or frame structure adapted to the contour of the mouse skull, and its material is also a non-magnetic material.

[0042] The headframe 210 has first mounting holes 212 on both sides, and the second connecting part 220 has second mounting holes 221. The first mounting holes 212 and the second mounting holes 221 are correspondingly arranged. The headframe 210 is fixed to the second connecting part 220 by bolts passing through the first mounting holes 212 and the second mounting holes 221. All bolts are made of non-magnetic, high-strength, lightweight materials.

[0043] In some embodiments, the head fixation component 200 is movably connected to the base 100, and the head fixation component 200 is movable along the width direction of the base 100. Specifically, the second connecting part 220 is movably connected to the base 100, and a guide rail 230 is designed between the second connecting part 220 and the base 100. The guide rail 230 is arranged along the width direction of the base 100 so that the head fixation component 200 can move along the width direction of the base 100. Limiting structures are provided at both ends of the guide rail 230 to prevent the head fixation component 200 from disengaging from the guide rail 230 during sliding. By adjusting the head fixation component 200 along the width direction of the base 100, it can be adapted to mice with different head widths, ensuring that the head fixation component 200 can fit tightly against both sides of the mouse's head, thus improving the stability of the fixation.

[0044] The screw-connected structure allows for convenient and quick assembly and disassembly, reducing animal injury. It enables rapid installation and removal of the head fixation component 200 from the base 100, is easy to operate, has high repeatability and positioning accuracy, and maintains high stability during magnetic resonance scanning, significantly reducing motion artifacts in the head of awake mice.

[0045] Combination Figure 5 As shown, in some embodiments, the head frame 210 has a protrusion 211 on the side away from the base 100, which is used to fit against the top of the mouse's head. The head frame 210 is an arc-shaped frame structure or a plate-like structure, with the protrusion 211 on the side away from the base 100. The protrusion 211 is an arc-shaped protrusion extending towards the direction of the mandibular fixation component 300, and its contour conforms to the surface contour of the mouse skull, ensuring a close fit to the mouse skull. The protrusion 211 avoids compressing the mouse skull and reduces stress response.

[0046] In some embodiments, the head fixation assembly 200 includes head frames 210 of various sizes to match the head sizes of different mice. The multi-size head frame 210 design allows for flexible adaptation to mice at different developmental stages and of different body sizes, enabling universal fixation of multiple experimental individuals using the same base 100, thus improving the compatibility and efficiency of the device. The multi-size head frame 210 can specifically match the head sizes of mice of different body sizes and developmental stages, eliminating the need for separate head fixation assemblies 200 for different mice and significantly improving the versatility of the device.

[0047] The head frame 210 is small in size, and its structure and placement have little impact on the natural behavior of mice. After scanning, multiple behavioral paradigm tests can still be performed, enabling repeated experiments on animals and improving the overall efficiency of the experiment.

[0048] In some embodiments, a pair of body fixation plates 400 are provided on one side of the base 100, and the body fixation plates 400 are arranged along the length of the base 100. The pair of body fixation plates 400 are made of non-magnetic high-strength material, symmetrically arranged on both sides of the upper surface of the base 100, and extend along the length of the base 100 to form a channel for accommodating the mouse's body. The height of the body fixation plates 400 is designed according to the height of the mouse's body to ensure that the mouse's body can be restrained from both sides without affecting the mouse's breathing and natural posture.

[0049] In use, the mouse is placed in the channel between a pair of body fixation plates 400. The body fixation plates 400 restrain the mouse's body from both sides. The mouse can be further secured to the body fixation plates 400 with bandages or tape to prevent significant body movement. Then, the position of the second connecting part 220 on the base 100 is adjusted, and the head frame 210 is connected to the second connecting part 220. The height of the pad 310 is adjusted to achieve stable fixation of the mouse's entire body, thus ensuring head stability in an awake state. The entire process is simple to operate, highly repeatable, and effectively maintains head stability in MRI scans of awake mice, significantly improving image signal-to-noise ratio and spatial resolution, and reducing motion artifacts. A second pad 410 is also provided between the body fixation plates 400 on the base 100 to prevent the body from sliding on the plates when the awake mouse struggles, cushioning pressure and protecting the mouse. It is usually made of silicone or soft sponge, with a soft texture that conforms to the body contours of mice of different sizes, further reducing movement interference.

[0050] In some embodiments, the base 100 is provided with a third connecting portion 500, which is used to connect the target animal fixation device to the MRI bed. The third connecting portion 500 is a connecting ear structure that is vertically installed on the upper surface or both sides of the base 100. The third connecting portion 500 also includes a third mounting hole 510. The structure of the third connecting portion 500 is adapted to the interface of the MRI bed. By passing a bolt through the third mounting hole 510 and tightening the nut, the base 100 can be connected to the bed interface of the MRI scanner. The high precision of the fit between the third connecting portion 500 and the third mounting hole 510 ensures the consistency of the device's positioning and mechanical stability on the MRI scanning bed, and avoids micro-movement of the device during scanning.

[0051] This device is specifically designed for magnetic resonance imaging experiments in awake mice. It is suitable for experimental mice at different developmental stages and of different strains, effectively improving imaging quality and the reproducibility of experimental data. It is widely used in biomedical research scenarios such as brain functional imaging and exploration of neural circuit mechanisms.

[0052] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application. Furthermore, unless otherwise specified, the embodiments and features described in the embodiments of this application can be combined with each other.

Claims

1. A target animal restraint device, characterized in that, For securing an conscious target animal, the target animal securing device includes: Base; A head fixing assembly is disposed on the base; A mandibular fixation assembly is disposed on the base, the mandibular fixation assembly having a support surface for supporting the mandible of the target animal, the mandibular fixation assembly being configured to adjust the height of the support surface relative to the base to adaptively pad the mandible of the target animal.

2. The target animal restraint device according to claim 1, characterized in that: The chin fixation assembly includes a pad, a first connecting part, and a locking structure. The first connecting part is disposed on the base. The pad is slidably connected to the first connecting part to move closer to or further away from the base. The locking structure is used to lock the pad at a target height.

3. The target animal restraint device according to claim 1, characterized in that: The mandibular fixation assembly includes pads of various thicknesses, which are detachably connected to the base.

4. The target animal restraint device according to claim 2 or 3, characterized in that: The pad includes a base, a first sidewall, and a second sidewall. The first sidewall and the second sidewall are respectively connected to both sides of the base and are disposed on both sides of the base along its length.

5. The target animal restraint device according to claim 1, characterized in that: The head fixation assembly includes a second connecting part and a head frame, the second connecting part being connected to the base, and the head frame being detachably connected to the second connecting part.

6. The target animal restraint device according to claim 1 or 5, characterized in that: The head fixing component is movably connected to the base so that the head fixing component can move along the width direction of the base.

7. The target animal restraint device according to claim 5, characterized in that: The headgear has a protrusion on the side away from the base, which is used to fit against the top of the target animal's head.

8. The target animal restraint device according to claim 5, characterized in that: The head fixation assembly includes head frames in various sizes.

9. The target animal restraint device according to claim 1, characterized in that: A pair of body fixing plates are provided on one side of the base, and the body fixing plates are arranged along the length of the base.

10. The target animal restraint device according to claim 1, characterized in that: The base is provided with a third connecting part, which is used to connect the target animal fixation device to the MRI bed.

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