Animal heating pad

Abstract

The present disclosure describes animal heating pads. A sample support system (100) for supporting small animals during preclinical imaging. A sample support system (100) includes an animal bed (110) for supporting a small animal and a heating system linked to the animal bed (110). The heating system comprises a thermal pad for influencing the temperature of the small animal when supported on an animal bed (110), the thermal pad comprising a graphitic layer (120). The heating system is adapted to control the energy supplied to the graphitic layer (120), thereby affecting the temperature of the small animal.

Description

Technical Field

[0001] The present invention relates to heating methods and systems for use with animal beds in imaging applications. Background Art

[0002] For preclinical imaging and for testing purposes, animals including rodents are often subjected to imaging techniques such as single photon emission computed tomography (SPECT), positron emission tomography (PET), computed tomography (CT), computer-assisted tomography (CAT), X-ray or magnetic resonance imaging techniques such as magnetic resonance imaging (MRI) to obtain real-time or photographic images without harming the animals. Since animals should remain still during imaging (e.g., scanning process), anesthesia is often performed. However, anesthetized animals (particularly rodents) may have difficulty maintaining their body temperature within a desired range, which may cause additional stress to the animals.

[0003] In view of this, heating systems are usually used to effectively regulate the body temperature of immobilized animals throughout the anesthesia and imaging process. In order not to deteriorate the quality of imaging, the heating systems and methods usually used need to be compatible with the corresponding requirements of the imaging technology.

[0004] Some existing heating systems for animal beds are based on hot air heating. Such heating systems usually require pneumatic coupling (air coupling) between the heating system and the bed. In addition, they are usually large in size and may require a heat exchanger. An example of a hot air heating system for an animal bed is described in U.S. Pat. No. 9,408,682 B2, describing a system having an animal bed, a heater positioned outside the animal bed, the heater being coupled on one side to an air pump for receiving unheated air, and on the other hand coupled to the animal bed by a channel for delivering heated air to the animal bed.

[0005] However, there is still room for improvement in heating systems and methods used in animal beds. Summary of the invention

[0006] It is an object of embodiments of the present invention to provide a good heating system and a corresponding method for heating an animal bed used for preclinical imaging of animals.

[0007] An advantage of embodiments according to the present invention is that the heating system and the corresponding method are compatible with preclinical imaging techniques used for animals, such as, for example, computed tomography (CT), X-ray imaging, positron emission tomography (PET), single photon emission computed tomography (SPECT), ultrasound imaging, optical imaging, magnetic resonance imaging (MRI), etc.

[0008] An advantage of embodiments according to the present invention is that the heating system and the corresponding method largely avoid the use of metals, since metals typically cause artifacts in imaging.

[0009] An advantage of embodiments according to the present invention is that the heating system does not use dense materials, thereby avoiding severe attenuation of, for example, X-rays.

[0010] An advantage of embodiments according to the invention is that the heating system is compact, where little space is available, thereby allowing easier integration in an animal bed.

[0011] The above objectives are achieved by the system and method described below.

[0012] In a first aspect, the present invention relates to a sample support system for supporting small animals during preclinical imaging, the sample support system comprising an animal bed for supporting the small animal and a heating system linked to the animal bed. The heating system comprises a heat pad for affecting the temperature of the small animal when supported on the animal bed. The heat pad comprises a graphite layer. The heating system is suitable for controlling the energy supplied to the graphite layer, thereby affecting the temperature of the small animal. According to some embodiments of the present invention, the energy supplied to the graphite layer may be electrical energy (e.g., electric current), which is converted into thermal energy in the graphite layer for affecting the temperature of the small animal. According to some embodiments of the present invention, the energy supplied to the graphite layer may be thermal energy (e.g., heat), which is thermally conducted by the graphite layer and transferred to the surroundings for affecting the temperature of the small animal.

[0013] The graphite layer may be a flake. In the embodiments where a flake is mentioned, reference is made to a structure where the thickness is much smaller than the dimensions of the width and length over which the structure extends (eg, the thickness is at most one tenth of these dimensions).

[0014] When thickness is mentioned in the exemplary embodiments, reference is made to the dimension of a structure along a local normal to the structure.

[0015] The lamellae may for example have an average thickness of between 10 μm and 1000 μm.An advantage of embodiments of the invention is that the thickness of the heating system is small and thereby the heating system is compact, since the amount of space available in an animal bed is limited.

[0016] The heating system may be adapted to supply energy via one or more connectors on the same side of the heat pad, the connector being external to the imaging portion of the animal bed. The one or more connectors may all be on the same side of the heat pad. The one or more connectors may all be on the same side of the heat pad relative to the length of the heat pad. In some embodiments, the heat pad may extend along the length of the animal bed and may be wrapped around at least one turn.

[0017] The heating system may be configured to induce an electric current in the graphite layer for controlling the energy supplied to the graphite layer. An advantage of embodiments of the present invention is that the good electrical properties (low resistivity) of the graphite layer may be used to cause heating of the graphite layer and thereby affect the temperature of a small animal positioned in the animal bed.

[0018] The heating system may include an adjustable power supply, and wherein the heat pad is electrically connected to the power supply via at least two electrical connections. Alternatively, the heat pad may be provided with electrical connections, and the power supply may be external to the sample support system but may be connected to the electrical connections of the heat pad. In yet other embodiments, the current may be induced in the graphite layer in a different manner (e.g., inductively or the like).

[0019] The heat pad may extend along the length of the animal bed and may wrap around at least one turn. At least two electrical connections from the heat pad to the power source may be positioned on the same side of the heat pad. The power source, the electrical connections and the heat pad may be arranged to form a closed circuit. An advantage of an embodiment of the present invention is that the electrical connections of the heat pad are positioned on one side of the heat pad, as electrical connections that are typically made of metal components may cause artifacts in some imaging techniques. When the electrical connections are on the same side of the heat pad, they can be more easily positioned outside the imaging portion of the bed. The heat pad may extend along the length of the animal bed and wrap around at least one turn. The power source, the at least two electrical connections and the heat pad form a closed circuit.

[0020] At the location of the electrical connector, the thermal pad may be wider than the average width of the thermal pad along the length of the thermal pad. An advantage of embodiments of the present invention is that the thermal pad at the location of the electrical connector is wider than average because it allows for a reduction in the heat generated due to the lower resistance in this area and because it allows for easier electrical connection. An advantage of embodiments of the present invention is that the thickness and surface area of ​​the thermal pad may be modified, designed and / or optimized for shaping the heat dissipation of the surface of the thermal pad and for shaping the electrical properties (e.g., resistivity).

[0021] The preclinical imaging modality may be at least one of: CT, SPECT, PET, ultrasound, magnetic resonance, or optical imaging.

[0022] The support may be adapted to support a rodent.

[0023] The heat pad can be covered with a shell material on at least one side, preferably on both sides. The shell material can be a carbon shell. The advantage of an embodiment using a carbon shell material is that it is lightweight and easy to clean while the heating system remains compact. The shell material can advantageously provide mechanical protection for the heat pad. In addition, it can make the hanger easier to clean. Carbon materials (such as, for example, carbon fiber tubes, but not limited to carbon fiber tubes) are generally relatively low in cost and have good strength and stiffness. In addition, such materials are generally transparent to radiation used in at least some types of imaging and do not introduce artifacts on the corresponding acquired images. In other examples, the shell material may include other materials such as plastics or ceramics, or different materials may be combined at different locations along the shell or on top of each other.

[0024] The graphite layer may be covered on one or both sides with a layer comprising an electrically insulating material. The electrically insulating material may be Kapton. An advantage of embodiments of the present invention is that the graphite layer may be electrically isolated from potentially conductive materials in the housing or other components of the sample support system.

[0025] The heating system may further or alternatively include a thermal power source thermally connected to the heat pad for controlling the thermal energy supplied to the graphite layer by controlling the temperature of the thermal power source. The thermal power source may be a power resistor. Thus, the supply of energy may be performed by supplying thermal energy (e.g., heat) from the same side of the heat pad relative to the length direction of the heat pad. The (one or more) connectors may be on a single side of the heat pad, and the (one or more) connectors are outside the imaging portion of the animal bed. Such (one or more) connectors may be on a single side of the heat pad relative to the length direction of the heat pad. In some embodiments, the heat pad may extend along the length of the animal bed and may be around at least one turn.

[0026] According to one aspect, the present invention also relates to an imaging system for preclinical imaging of small animals, which imaging system includes a sample support system according to one of the embodiments described above, and an imager for preclinical imaging of small animals positioned on the sample support system.

[0027] Particular and preferred aspects of the invention are set out in the accompanying independent and dependent claims. Features of the dependent claims may be combined with features of the independent claims and with features of further dependent claims (such as indicated rather than only as explicitly set out in the claims).

[0028] To summarize the present invention and the advantages achieved over the prior art, certain objects and advantages of the present invention have been described above. Of course, it will be appreciated that not all of these objects or advantages may be achieved by every specific embodiment of the present invention. Thus, for example, it will be apparent to those skilled in the art that the present invention may be embodied or performed in a manner that achieves or optimizes one advantage or a group of advantages as presented herein without necessarily achieving other objects or advantages as may be presented or suggested herein.

[0029] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiment(s) described hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The present invention will now be further described by way of example with reference to the associated drawings, in which

[0031] In the figure:

[0032] Figure 1 A sample support system according to an embodiment of the present invention is shown.

[0033] Figure 2 Thermal distribution using a sample support system according to an embodiment of the present invention is shown.

[0034] Figure 3 A schematic diagram of an imaging system according to an embodiment of the invention is shown.

[0035] The accompanying drawings are only schematic and non-restrictive. For illustrative purposes, the sizes of some components may be exaggerated and not represented to scale in the accompanying drawings. The sizes and relative sizes do not necessarily correspond to actual embodiments of the present invention.

[0036] Reference signs used in the claims shall not be construed as limiting the scope. DETAILED DESCRIPTION

[0037] While the invention has been illustrated and described in detail in the drawings and accompanying description, such illustration and description are to be considered illustrative or exemplary and not restrictive. The invention is not limited to the disclosed embodiments.

[0038] By studying the drawings, the present disclosure and the appended claims, those skilled in the art can understand and implement other variations of the disclosed embodiments in practicing the claimed invention. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality.

[0039] The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

[0040] The following description details certain embodiments of the present invention. However, it will be appreciated that no matter how detailed the following description appears in text, the present invention can be practiced in many ways and is therefore not limited to the disclosed embodiments. It should be noted that the use of a particular term in describing certain features or aspects of the present invention should not be taken as implying that the term is redefined herein to be limited to including any particular characteristics of the feature or aspect of the present invention with which the term is associated.

[0041] In a first aspect, the present invention relates to a sample support system for supporting small animals during preclinical imaging. The sample support system includes an animal bed for supporting small animals and a heating system linked to the animal bed. Such an animal bed can be part of a larger system (e.g., an imaging system for preclinical imaging of small animals). In an embodiment of the present invention, when referring to small animals, the latter can generally refer to rodents, such as, for example, mice, rats, squirrels, prairie dogs, porcupines, beavers, guinea pigs, hamsters, etc., but may also include other animals, such as, for example, rabbits, hares, pikas or (more generally) groups of lagomorphs, or, for example, birds, livestock, farm animals, etc. According to an embodiment of the present invention, the sample support system also includes a heating system, which includes a heat pad for affecting the temperature of the small animal when it is supported on the animal bed. The latter allows affecting (e.g., controlling) the temperature of the animal positioned on the animal bed. Since, for example, during preclinical imaging, animals are often anesthetized and may have difficulty maintaining their body temperature, the latter allows more animal-friendly diagnosis and treatment. According to an embodiment of the present invention, the heat pad includes a graphite layer. The heating system is adapted to control the energy supplied to the graphite layer, thereby influencing the temperature of the small animal.The use of the graphite layer allows good heat transfer between the heating system and the rest of the animal bed, and thereby to the animal positioned thereon.

[0042] According to some embodiments of the present invention, the energy supplied to the graphite layer may be electrical energy (e.g., electric current), which is converted into thermal energy in the graphite layer for influencing the temperature of the small animal. According to some embodiments of the present invention, the energy supplied to the graphite layer may be thermal energy (e.g., heat), which is thermally conducted by the graphite layer and transferred to the surroundings for influencing the temperature of the small animal.

[0043] In an embodiment of the present invention, the heating system thus has a heat pad comprising a graphite layer, which may be a thin sheet. The layer may be self-supporting or may be positioned on a substrate. The layer may have an average thickness between 10 μm and 1000 μm. An advantage of an embodiment of the present invention is that the thickness of the heating system is small and thereby the heating system is compact, since the amount of available space in the animal bed is limited. The graphite layer may have a shape comprising at least one circle (e.g., having a U-shape), although embodiments are not limited thereto. It may be shaped according to a specific pattern, which corresponds to the location where heat needs to be transferred to the animal bed. In some embodiments, the layer is a self-supporting layer that can be easily cut into a predetermined shape, where even complex shapes are required, thereby allowing heat to be provided at appropriate locations. The shape may be selected to interfere as little as possible with the imaging system and imaging technology, thereby avoiding artifacts in the image obtained.

[0044] In embodiments where the energy supplied to the graphite layer is electrical energy converted by the graphite layer itself by resistive heating, the shape of the graphite layer may be such that it forms part of a closed circuit. In advantageous embodiments, the local thickness and width of the graphite layer may be selected so as to have an appropriate resistivity distribution and, therefore, an appropriate heat dissipation distribution in the layer by resistive heating. The most appropriate distribution may be selected depending on the sample support system. By locally selecting the thickness and width of the layer, the amount of heat dissipated in the layer may be selected. In other words, by varying the width and length of the graphite pattern, the heat, power and current characteristics in the graphite layer may be adjusted.

[0045] In some embodiments, for example, when a thermal power source is used and energy is transferred to the graphite layer, the graphite layer need not form a closed circuit.

[0046] An advantage of embodiments of the present invention is that the graphite layer does not include metal particles and therefore does not substantially interfere with most imaging techniques. Another advantage of embodiments of the present invention is that the graphite layer is generally a good and uniform heat sink.

[0047] The graphite layer may be flexible and / or foldable. Such flexibility may be used at locations where the graphite layer contacts the energy source. Where electrical energy is supplied to the graphite layer, electrical contact may be established by securing an electrical wire to the graphite layer (e.g., by bonding, gluing (e.g., using a conductive glue), welding, wrapping the electrical wire in a sheet-like portion of the graphite layer, or the like). Similarly, where thermal energy is supplied to the graphite layer, a thermal conductor (such as a metal portion) may be secured to the graphite layer in any suitable manner that allows good thermal contact.

[0048] The heating system may also typically include a power supply (usually adjustable). In the case where electrical energy is supplied to the graphite layer, such a power supply may be any suitable power supply for providing current to the graphite layer. Such a source may be implemented, for example, in a printed circuit board (PCB), although embodiments are not limited thereto. Although it is advantageous to integrate the power supply in the sample support system, it may also be a component that can be positioned further away. The power supply may be suitable for providing appropriate current signals to the layers of the graphite layer. The latter may be executed, for example, under the command of a controller, which may also be a separate component or a component integrated on a printed circuit board. In some embodiments, the power supply may be configured to provide a modulated current signal to the graphite layer. Such modulated current signals may, for example, be pulse width modulated current signals, because these signals easily allow control of the heat generated in the graphite layer.

[0049] Alternatively, or in addition, the heating system may also include a thermal power source, and the graphite layer may be heated by thermal conductivity. An example of a thermal power source is, for example, a power resistor, although other power sources may also be used. When a thermal power source is used, in order to protect other components of the system, an insulating material may be used to shield the thermal power source from the other components.

[0050] The sample support system may also optionally include a holding component (such as, for example, a bracket) for mechanically holding the power source. In some embodiments, such a bracket may be a bracket for holding a printed circuit board. The holding component may also be configured to hold different components of the sample support system, optionally with thermal insulation between the components.

[0051] In some embodiments, the sample support system may further include a monitoring and / or control system for monitoring parameters and / or for controlling other elements of the sample support system, such as, for example, vital parameters of the animal (such as respiration, heart rate, ECG, temperature, etc.). Such monitoring and / or control may be integrated with the power supply as described above (e.g., on the same printed circuit board). Alternatively, such monitoring and / or control system may be implemented on a separate platform (e.g., on a separate printed circuit board).

[0052] The animal bed may comprise a plate-like or shell-like component which may serve as a surface on which the animal may be positioned. The graphite layer may advantageously be positioned in contact with the plate-like or shell-like component to allow conductive heat transfer to the plate-like or shell-like component and thereby to the small animal positioned thereon. In some embodiments, the animal bed may comprise two plate-like or shell-like components between which the graphite layer may be positioned. The plate-like or shell-like components may be made of a material that is easy to clean, such as, for example, carbon fiber. Furthermore, advantageously, a material is selected for the plate-like or shell-like component(s) that does not interfere, or only interferes very little, with the radiation used for imaging, to avoid artifacts.

[0053] The system according to an embodiment of the present invention may also include a connector for connecting the sample support system to the rest of the imaging system in which the sample support system is used. Such a connector may be, for example, a metal block with specific fixing means for fixing it, but other types of materials may also be used.

[0054] In some embodiments, the system may also include anesthesia tubing, anesthesia infusion and removal, etc. Furthermore, those skilled in the art will appreciate that there may also be other components that are often present in animal beds according to the current state of the art.

[0055] By way of illustration, the embodiments of the present invention are not limited. Figure 1 An exemplary sample support system 100 is shown in FIG. The sample support system 100 includes an animal bed 110 and a graphite layer 120. In the example shown, the graphite layer 120 has a specific patterned shape. The layer 120 is U-shaped and has two legs 122, 124, each of which has a wide portion 126, 128, and both wide portions 126 and 128 are positioned on the same side. In this example, the electrical connection between the printed circuit board 130 and the graphite layer 120 is made using wires (not shown) between the two wide portions 126, 128 of the graphite layer 120 and the printed circuit board 130. By using the wide portions 126, 128 of the graphite layer 120, the amount of heat dissipation that occurs at this location (i.e., close to the printed circuit board) due to resistive heating in the graphite layer 120 is limited. Therefore, the heat dissipated in the smaller portion of the legs 122, 124 will be higher. In this example, the power supply on the printed circuit board 130 is an electronics board that includes both a power supply for supplying current to the graphite layer 120, as well as other electrical components that support the system for, for example, monitoring the vital signs of an animal (such as, for example, respiration, ECG, temperature) and / or controlling other features of the system that need to be controlled electronically. Figure 1 The sample support system shown in the figure also illustrates a holding bracket 140 for holding an electronic board (PCB), an anesthesia tube 150, a connector 160 as a metal bed block, an outer carbon fiber shell 170 and an inner carbon fiber shell 172, mounting elements 180, 182 and an upper cover 190, and the graphite layer 120 is positioned between the outer carbon fiber shell 170 and the inner carbon fiber shell 172.

[0056] To further illustrate, in Figure 2 Thermal heating of a sample support system using a specific embodiment of the present invention is shown in FIG. Figure 2 A thermal (infrared) image of the sample support system is shown. As can be seen, an accurate heat diffusion is obtained. The latter confirms that the system allows accurate heating of an animal positioned on an animal bed.

[0057] In another aspect, the present invention relates to an imaging system for preclinical imaging of small animals. Such imaging systems may, for example, utilize computed tomography (CT), X-ray imaging, positron emission tomography (PET), single photon emission computed tomography (SPECT), ultrasound imaging, optical imaging, magnetic resonance imaging (MRI), etc. The imaging system typically includes an imager suitable for preclinical imaging (although imaging may also be performed at other times during the diagnosis, treatment or study of small animals) and a sample support system according to the first aspect of the present invention. Since the components of the imager typically need to surround the small animal positioned on the sample support system, an advantage is that the sample support system according to an embodiment of the present invention can be compact. The imager can be a scanning device or based on other imaging methods. It should be noted that the components of such imagers (including but not limited to radiation sources and detectors) are generally known to those skilled in the art and are therefore not discussed here. As an illustration, in Figure 3 A schematic diagram of such an imaging system 200 including an imager 202 and a sample support system 100 is shown in FIG.

[0058] Reference numerals

[0059] 100 Sample Support System

[0060] 110 Animal Bed

[0061] 120 Graphite Layer

[0062] 122,124 Legs

[0063] 126,128 Width

[0064] 130 Power supply, printed circuit board

[0065] 140 Holding bracket

[0066] 150 Anesthesia Tube

[0067] 160 Connectors

[0068] 170 External carbon shell

[0069] 172 Inner Carbon Shell

[0070] 180,182 Mounting components

[0071] 190 Upper cover

[0072] 200 Imaging System

[0073] 202 Imager

Claims

1. A sample support system (100) for supporting small animals during preclinical imaging, the sample support system (100) comprising an animal bed (110), the animal bed (110) being used to support the small animal; and a heating system, the heating system being linked to the animal bed (110), The heating system comprises a heat pad for influencing the temperature of the small animal when supported on the animal bed (110), the heat pad comprising a graphite layer (120), and The heating system is adapted to control the energy supplied to the graphite layer (120), thereby affecting the temperature of the small animal.

2. The sample support system (100) according to claim 1, wherein: The graphite layer (120) is a thin layer having an average thickness between 10 μm and 1000 μm.

3. The sample support system (100) according to any one of the preceding claims, wherein: The heating system is adapted to supply energy via one or more connections on the same side of the thermal pad, the connections being external to the imaging portion of the animal bed.

4. The sample support system (100) according to any one of the preceding claims, wherein: The one or more connectors are all located on the same side of the thermal pad relative to the length direction of the thermal pad.

5. The sample support system (100) according to any one of the preceding claims, wherein: The heat pad extends along the length of the animal bed and wraps at least one circle.

6. The sample support system (100) according to any one of the preceding claims, wherein: The heating system is configured for inducing an electric current in the graphite layer (120) for controlling the energy supplied to the graphite layer (120).

7. The sample support system (100) according to any one of the preceding claims, wherein: The heating system comprises a power source (130), and wherein the thermal pad is electrically connected to the power source (130) via at least two electrical connections.

8. The sample support system (100) according to any one of the preceding claims, wherein: The heat pad extends along the length of the animal bed (110) and around at least one turn, and wherein the at least two electrical connections from the heat pad to the power source (130) are positioned on the same side of the heat pad.

9. The sample support system (100) according to any one of claims 7 to 8, wherein: The power source (130), the electrical connector and the thermal pad form a closed circuit.

10. The sample support system (100) according to any one of claims 7 to 9, wherein: The thermal pad at the location of the electrical connector is wider than an average width of the thermal pad along the length of the thermal pad.

11. The sample support system (100) according to any one of the preceding claims, wherein: The preclinical imaging modality is at least one of: CT, SPECT, PET, ultrasound, magnetic resonance, or optical imaging.

12. The sample support system (100) according to any one of the preceding claims, wherein: The animal bed (110) is adapted to support a rodent.

13. The sample support system (100) according to any one of the preceding claims, wherein: The thermal pad is covered with housing material on at least one side, preferably on both sides.

14. The sample support system (100) according to any one of the preceding claims, wherein: The graphite layer (120) is covered on one or both sides with a layer comprising an electrically insulating material.

15. The sample support system (100) according to any one of the preceding claims, wherein: The electrically insulating material includes Kapton.

16. The sample support system (100) according to any one of the preceding claims, wherein: The heating system further comprises a thermal power source thermally connected to the heat pad for controlling the energy supplied to the graphite layer (120) by controlling the temperature of the thermal power source.

17. The sample support system (100) according to claim 16, wherein: The thermal power source is a power resistor.

18. An imaging system (200) for preclinical imaging of small animals, the imaging system (200) comprising a sample support system (100) according to any one of the preceding claims, and an imager (202), the imager (202) being used for preclinical imaging of small animals positioned on the sample support system (100).

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