Tumor radiotherapy positioning and fixing device

Abstract

The invention relates to a positioning and fixing device for tumor radiotherapy, and belongs to the technical field of medical instruments. In order to solve the problems of poor radiotherapy effect, body burden of a patient and the like caused by the influence of the body shape change of the patient on radiotherapy positioning at present, a headrest checking mechanism, a mold forming mechanism, a trunk wrapping and fixing mechanism, a lower limb limiting mechanism and a main controller are arranged, and the headrest checking mechanism corresponds to the head position of the patient in a lying position; the mold forming mechanism is adjacent to the headrest checking mechanism, the trunk wrapping and fixing mechanism is arranged above the mold forming mechanism, the lower limb limiting mechanism is arranged at the end, close to the tail, of the mold forming mechanism, and the main controller is arranged at the rear end of the lower limb limiting mechanism; the main controller is in communication connection with the headrest checking mechanism, the mold forming mechanism and the trunk wrapping and fixing mechanism. The device can be adaptively adjusted according to the posture of a patient, so that the influence of the body shape change of the patient on the radiotherapy precision is avoided, and the radiotherapy positioning time and the workload of doctors are shortened.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a positioning and fixing device for tumor radiotherapy. Background Art

[0002] Tumor radiotherapy is a localized radical treatment method whose fundamental goal is to maximize tumor destruction, increase local tumor control, and reduce the probability of radiation complications in surrounding normal tissues. During radiotherapy, it is necessary to ensure accurate and repetitive positioning and fixation of the patient's body position, so that the patient maintains accurate limb positioning and reduction throughout the radiotherapy process to ensure that the radiotherapy rays accurately act on the lesion. Therefore, body fixation is one of the most important links in tumor radiotherapy, directly related to whether the target area can be accurately irradiated and whether endangered organs can be effectively protected.

[0003] Traditional positioning devices tightly wrap the patient's upper body during use, and a single treatment session can last up to 20-30 minutes, which can easily cause discomfort to the patient. Furthermore, radiotherapy cycles are long, and patients may experience changes in body shape, tumor shrinkage, or normal tissue edema between treatments, leading to changes in body position. Positioning adjustments must be made based on the patient's current circumstances. However, traditional positioning devices position the patient only by reference to the initial positioning markers during subsequent treatment. If the patient experiences these changes in body shape, tumor shrinkage, or normal tissue edema, the positioning markers will shift after initial positioning according to the markers, resulting in significant errors in the accuracy of radiotherapy and reduced treatment precision.

[0004] Since radiotherapy requires multiple treatments and a certain interval, the body shape of most patients will change during this period. For example, some patients lose weight, while others gain weight. The change in body shape increases the difficulty of positioning during radiotherapy. In particular, the huge change in body shape before and after multiple treatments can easily cause radiotherapy errors, affect the effect of radiotherapy, and cause damage to normal cells around the tumor, increasing the patient's physical burden. Based on this, a tumor radiotherapy positioning and fixation device was developed to solve the above problems. Summary of the Invention

[0005] In response to the defects existing in the above-mentioned prior art, the present invention aims to provide a tumor radiotherapy positioning and fixation device. By setting a mold forming mechanism, a torso wrapping and fixing mechanism, a lower limb limiting mechanism, and a headrest calibration mechanism, and combining the intelligent cooperation of sensors and controllers, the patient's radiotherapy positioning and fixation are more accurate and efficient. The device can adaptively adjust according to the patient's body shape to avoid the impact of the patient's body shape changes on the radiotherapy accuracy during radiotherapy. At the same time, it greatly shortens the radiotherapy positioning time, reduces the doctor's workload, and effectively solves the problems in the background technology.

[0006] In order to achieve the above object, the technical solution of the present invention is as follows: A positioning and fixing device for tumor radiotherapy comprises a base plate body, and the top of the base plate body is provided with the following components in order from the beginning to the end: A headrest calibration mechanism corresponds to the position of the patient's head in a supine position, and the patient's position is determined by the pressure value of the headrest calibration mechanism; The mold forming mechanism is set up next to the headrest calibration mechanism, and performs adaptive molding according to the patient's body shape changes at different stages of radiotherapy; A torso wrapping and fixing mechanism is provided above the mold forming mechanism and is used to wrap and fix the patient's torso during radiotherapy; The lower limb limiting mechanism is arranged at one end of the mold forming mechanism near the tail, and is used to fix the patient's lower limbs; The main controller is arranged at the rear end of the lower limb limiting mechanism, and the main controller is respectively communicated with the headrest calibration mechanism, the mold forming mechanism and the torso wrapping and fixing mechanism.

[0007] As a further preferred embodiment of the above technical solution, the mold forming mechanism includes: A torso support assembly movably connected to the headrest calibration mechanism; The hip lifting assembly is provided at the rear end of the torso supporting assembly, and a variable resistance component is provided at the bottom of the hip lifting assembly to regulate the current in the torso supporting assembly through the variable resistance component; There are two clamping airbags, both located on both sides of the body support component.

[0008] Based on the above technical solution, further, the body support component includes: The supporting airbag is connected to the base plate body, and the supporting airbag is in an arched structure when inflated; The back support plate is located on the top of the support airbag, and a capsule containing electrorheological fluid is provided on the top of the back support plate.

[0009] Based on the above technical solution, the hip lifting assembly further includes: The buttocks support plate is arranged at the rear end of the back support plate, and the middle part of the buttocks support plate is concave; The lifting airbag is arranged on the inner side of the edge of the hip support plate.

[0010] A further preferred solution is: the variable resistance component includes: The cylinder is arranged on the top of the base plate body; The piston is connected to the bottom of the hip support plate and is movably inserted into the cylinder; The resistance coil is wound on the piston member and is connected to the capsule containing the electrorheological fluid via a wire passing through the cylinder.

[0011] As a further preferred embodiment of the above technical solution, the torso wrapping and fixing mechanism includes: A thermoplastic wrapping component, which is located on one side of the mold forming mechanism when not in use and is wrapped around the patient's torso after being thermoplastically deformed when in use; The restraint assembly is movably connected to the base plate body and is located at the rear end of the thermoplastic wrapping assembly.

[0012] Based on the above technical solution, further, the thermoplastic wrapping component includes: A winding shaft is provided on one side of the mold forming mechanism; The thermoplastic film is wound on a winding shaft. In a use state, the free end of the thermoplastic film is passed over the upper part of the patient's torso and then fixed to the other side of the mold forming mechanism; The resistance wire is arranged along the axial direction of the winding shaft. When the resistance wire is energized and heated, the thermoplastic film changes from hard to soft.

[0013] Based on the above technical solution, the headrest calibration mechanism further includes: The pillow member is connected to the base plate body, and the rear end of the pillow member is provided with a supporting plate connected to the mold forming mechanism; The pressure calibration components are arranged on both sides of the pillow. The pressure value of the patient's shoulder is fed back through the pressure calibration components to achieve unified positioning of the patient's radiotherapy treatment.

[0014] A further preferred embodiment of the above technical solution is that the device further comprises a gripping mechanism arranged at the head end of the base body, and a pressure measuring structure for feeding back the patient's gripping strength is arranged on the gripping mechanism.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. By setting up a mold forming mechanism and inflating the support airbag under the patient's torso, the support airbag drives the length of the resistance coil connected to the circuit in the variable resistance component to shorten during the expansion process, and the resistance of the resistance coil decreases, so that the current in the connected circuit increases. By utilizing the increase and change of the current field, the bag containing the electrorheological fluid changes from liquid to solid according to the squeezing of the patient's back, thereby realizing adaptive molding of the patient's body shape changes at different stages of radiotherapy. At the same time, the clamping airbags on both sides of the patient's torso and the lifting airbags on the buttocks are used to achieve multi-directional clamping and limiting of the patient. In the process of the patient's torso being converted from an inclined state to a horizontal state, the pressure value and position calibration are achieved through the contact and squeezing of the patient's shoulder on the pressure sensor 2, thereby ensuring that the patient is treated in the same position as the initial radiotherapy and preventing the radiotherapy position from being affected by the patient's body shape changes.

[0016] 2. By setting up a torso wrapping and fixing mechanism and setting a heating structure according to the characteristics of the thermoplastic film, the heated and softened thermoplastic film is tightly covered on the patient's torso to fix it in place. At the same time, the front and rear ends of the thermoplastic film are fixed respectively with a traction hook and a position-adjustable restraint component, effectively preventing the patient's upper body from swaying during radiotherapy and reducing the impact of breathing on chest fluctuations.

[0017] 3. The device of the present invention can shorten the time for positioning during radiotherapy and reduce the workload of radiotherapy doctors. Currently, doctors face many different patients every day and need to calibrate according to the changes in each patient's body shape, which is time-consuming. The device can realize adaptive mode positioning calibration according to the patient's body shape. It only needs to observe and check the initial position and input the pressure value to complete the positioning, which greatly reduces the workload of radiotherapy doctors and effectively saves positioning time. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for describing the embodiments or the prior art.

[0019] Figure 1 This is a schematic diagram of the overall structure of a positioning and fixing device for tumor radiotherapy according to the present invention; Figure 2 It is a schematic diagram of the overall structure of the present invention from another angle; Figure 3 It is a structural schematic diagram of the headrest calibration mechanism of the present invention; Figure 4 It is a structural schematic diagram of the pressure calibration assembly of the present invention; Figure 5 Schematic diagram of the structure of the lower limb limiting mechanism of the present invention; Figure 6 It is a schematic diagram of the specific structure of the lower limb limiting mechanism of the present invention; Figure 7 It is a structural schematic diagram of the mold forming mechanism of the present invention; Figure 8 Schematic diagram of the cooperation relationship between the various parts of the mold forming mechanism of the present invention; Figure 9 is a schematic longitudinal section of the mold forming mechanism of the present invention; Figure 10 It is a schematic structural diagram of the torso wrapping and fixing mechanism of the present invention; Figure 11 is a cross-sectional schematic diagram of the torso wrapping and fixing mechanism of the present invention; Figure 12 is a schematic structural diagram of the thermoplastic wrapping assembly of the present invention; Figure 13 is a schematic longitudinal section of the thermoplastic wrap assembly of the present invention; In the figure: 1. Base plate body; 2. Headrest calibration mechanism; 21. Pillow member; 22. Pressure calibration assembly; 221. Sliding column; 222. Adjustment rod; 223. Pull hook; 224. Second pressure sensor; 3. Mold forming mechanism; 31. Torso support assembly; 311. Support airbag; 312. Back support plate; 313. Electrorheological fluid-containing bladder; 32. Hip lifting assembly; 321. Hip support plate; 322. Lifting airbag; 33. Clamping airbag; 34. Variable resistance member; 341. Cylinder; 342. Piston member ; 343. Resistance coil; 4. Torso wrapping and fixing mechanism; 41. Thermoplastic wrapping assembly; 411. Winding shaft; 412. Thermoplastic film; 413. Resistance wire; 42. Constraint assembly; 421. Elastic fixing belt; 422. Buckle; 5. Lower limb limiting mechanism; 51. Thigh fixing part; 511. Arched support block; 512 First elastic restraint belt; 52. Foot fixing part; 521. Ankle joint placement slot; 522. Second elastic restraint belt; 6. Main controller; 7. Gripping mechanism; 71. Pressure sensor 1; 8. Support plate. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0021] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "front end", "back end", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0022] It should also be noted that, in the description of this application, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0023] It should be understood that although the terms "first", "second", etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, the first element may be referred to as the second element, and similarly, the second element may be referred to as the first element. It should also be understood that when explaining an element, although not explicitly described, the element is interpreted as including an error range, which should be within the acceptable deviation range of the specific value determined by those skilled in the art. For example, "approximately", "approximately" or "substantially" can mean within one or more standard deviations and are not limited here.

[0024] Example 1: Reference Figures 1-6 The present invention discloses a positioning and fixing device for tumor radiotherapy, comprising a base plate body 1. The top of the base plate body 1 is provided with a gripping mechanism 7, a headrest calibration mechanism 2, a mold forming mechanism 3, a trunk wrapping and fixing mechanism 4, a lower limb limiting mechanism 5 and a main controller 6 in sequence from the head to the tail. The headrest calibration mechanism 2 corresponds to the position of the patient's head in a supine position, and the patient's positioning is determined by the pressure value of the headrest calibration mechanism 2. The mold forming mechanism 3 is arranged adjacent to the headrest calibration mechanism 2, and adaptive molding is performed according to the patient's body shape changes at different stages of radiotherapy. The trunk wrapping and fixing mechanism 4 is provided with a gripping mechanism 7, a headrest calibration mechanism 2, a mold forming mechanism 3, a trunk wrapping and fixing mechanism 4, a lower limb limiting mechanism 5 and a main controller 6 in sequence from the head to the tail. The headrest calibration mechanism 2 corresponds to the position of the patient's head in a supine position, and the patient's positioning is determined by the pressure value of the headrest calibration mechanism 2. The mold forming mechanism 3 is arranged adjacent to the headrest calibration mechanism 2, and adaptive molding is performed according to the patient's body shape changes at different stages of radiotherapy. The wrapping and fixing mechanism 4 is arranged above the mold forming mechanism 3, and is used to cover and fix the patient's torso during radiotherapy. The lower limb limiting mechanism 5 is arranged at one end of the mold forming mechanism 3 near the tail, and is used to fix the patient's lower limbs. The main controller 6 is arranged in a box body at the rear end of the lower limb limiting mechanism 5, and the main controller 6 is communicated with the headrest calibration mechanism 2, the mold forming mechanism 3 and the torso wrapping and fixing mechanism 4 respectively. An electronic display screen is provided on the outside of the main controller 6, and the various data display values of the patient during the positioning and fixation process are observed in real time through the electronic display screen.

[0025] like Figure 2 As shown, the gripping mechanism 7 includes two gripping rods vertically connected to the base body 1, and a number of pressure measuring structures are arranged on the gripping rods from top to bottom. During radiotherapy, the patient raises both hands above the head to grasp the gripping rods; in this embodiment, the pressure measuring structure is a pressure sensor 71, and the pressure sensor 71 is communicated with the main controller 6 to provide feedback on the patient's gripping strength.

[0026] like Figure 3As shown, the headrest calibration mechanism 2 includes a pillow part 21 and a pressure calibration component 22. The pillow part 21 is connected to the base plate body 1. The pillow part 21 is made of flexible material (such as silicone, etc.). The middle part of the pillow part 21 adopts a concave design, and the concave part is used to position the patient's head. The pillow part 21 is movably connected to the mold forming mechanism 3 through the support plate 8, wherein one end of the support plate 8 is hinged to the rear end of the pillow part 21, and the other end of the support plate 8 is fixedly connected to the mold forming mechanism 3. The pressure calibration component 22 is arranged on the left and right sides of the pillow part 21. The pressure value of the patient's shoulder is fed back through the pressure calibration component 22. When the current pressure value is adjusted to the same as the pressure value (set value) of the first radiotherapy, the patient's position adjustment is stopped to ensure that the patient's position is consistent for each radiotherapy, and to avoid the influence of the patient's body shape changes during the radiotherapy period (such as an interval of 2 to 3 months) on the accuracy and effect of radiotherapy.

[0027] Specifically, refer to Figure 4 The pressure calibration component 22 includes a sliding column 221 and an adjusting rod 222. The sliding column 221 is movably connected to both sides of the headrest. The height of the sliding column 221 can be flexibly adjusted according to the patient's body shape. The adjusting rod 222 is vertically movably connected to the sliding column 221. The rear end of the adjusting rod 222 is a U-shaped structure, the upper end of which is bent into a traction hook 223, and the lower end is connected to a pressure sensor 224, which is connected to the mold forming mechanism 3 through the traction hook 223. The pressure value of the patient's shoulder in the process of moving toward the front end of the base plate body 1 is detected by the pressure sensor 224. When the current pressure value is equal to the set value, the pressure sensor 224 transmits a signal to the main controller 6, and the main controller 6 sends a corresponding instruction action.

[0028] like Figure 5-6 As shown, the lower limb limiting mechanism 5 includes a thigh fixing part 51 and a foot fixing part 52. Two thigh fixing parts 51 are provided and both are located at the rear end of the mold forming mechanism 3. Each thigh fixing part 51 includes an arch support block 511 and a first elastic restraint belt. The patient's thigh is placed on the arch support block 511 and fixed with the first elastic restraint belt. Each foot fixing part 52 includes an ankle joint placement groove 521 and a second elastic restraint belt 522. The patient's foot is placed in the ankle joint placement groove 521 and the ankle joint is fixed with the second elastic restraint belt 522. In this embodiment, the arch support block 511 and the ankle joint placement groove 521 can be slid and adjusted in the width direction of the base plate body 1 respectively to adapt to the patient's flexible adjustment after the body shape changes at different stages of radiotherapy.

[0029] Example 2: Since the patient's body shape may change over a long period of time during radiotherapy (compared to gaining weight or losing weight during the first radiotherapy), in order to enable patients of different body shapes to be quickly positioned, the mold forming mechanism 3 is further optimized based on the above embodiment 1.

[0030] like Figure 7-9 As shown, the mold forming mechanism 3 includes a torso support component 31, a hip lifting component 32 and a clamping airbag 33. The torso support component 31 is movably connected to the pillow component 21. The hip lifting component 32 is arranged at the rear end of the torso support component 31. Two clamping airbags 33 are provided and are both located on both sides of the torso support component 31. The clamping airbags 33 on both sides are used to clamp the two sides of the patient's torso accordingly.

[0031] Specifically, the torso support assembly 31 includes a support airbag 311 and a back support plate 312. The support airbag 311 has an arched structure. Both sides of the support airbag 311 are fixedly connected to the base plate body 1. When inflated, the support airbag 311 arches upward to support the back support plate 312. The back support plate 312 is located on the top of the support airbag 311. A capsule 313 containing electrorheological fluid is also provided on the top of the back support plate 312.

[0032] In this embodiment, the electrorheological fluid in the capsule is an intelligent material whose rheological properties can achieve rapid and reversible liquid-solid phase transition through an external electric field. The electrorheological fluid is composed of high-dielectric-constant solid particles (such as TiO2 gel and nickel core-shell particles) dispersed in a low-dielectric-constant insulating liquid (such as silicone oil and mineral oil) to form a suspension system. Under the action of the electric field, the particles polarize to form a chain structure, resulting in a sharp increase in viscosity (up to 10⁻³ arc seconds), which instantly returns to its original state after the power is removed.

[0033] Reference Figure 8 The hip support component 32 includes a hip support plate 321 and a lifting airbag 322. The hip support plate 321 is integrally formed and connected to the tail end of the back support plate 312, and the middle part of the hip support plate 321 is a smooth concave structure. The lifting airbag 322 is arranged on the inner side of the edge of the hip support plate 321, and the lifting airbag 322 is used to squeeze and fix the patient's buttocks.

[0034] like Figure 8-9As shown, a variable resistance member 34 is provided at the bottom of the hip support assembly 32. The variable resistance member 34 regulates the current field in the bladder, converting the electrorheological fluid from a liquid state to a solid state. The variable resistance member 34 forms a specific shape according to the compression of the bladder by the patient's back, and realizes personalized molding after each change in the patient's body shape. Specifically, the variable resistance member 34 includes a cylinder 341, a piston 342 and a resistance coil 343. The cylinder 341 is fixedly connected to the top of the base body 1, and the piston 342 is connected to the bottom of the hip support plate 321. The piston 342 includes a piston rod and a piston head. The top end of the piston rod is fixedly connected to the hip support plate 321, and the bottom end of the piston rod is connected to the piston head. The piston rod is movably inserted into the cylinder 341. The piston head is sealed to the side wall of the cylinder 341. The resistance coil 343 is wound on the piston rod. A wire is passed through the side wall of the cylinder 341. One end of the wire contacts the resistance coil 343, and the other end extends to connect to the bladder 313 containing the electrorheological fluid.

[0035] In this embodiment, the support airbag 311 is connected to the clamping airbag 33 and the lifting airbag 322 via an internal passage. A magnetic valve is installed at the connection point between the support airbag 311, the clamping airbag 33, and the lifting airbag 322. This magnetic valve utilizes existing technology and is a device that uses electromagnetic force to control the flow of a medium. The valve's open and close state is adjusted by varying the strength of a magnetic field. A magnetic valve typically consists of an electromagnet, a valve body, and a valve core, enabling rapid and reliable fluid flow control. The magnetic valve only opens when the air pressure within the support airbag 311 reaches a set threshold. In this embodiment, the threshold is set to greater than half the full air pressure. In other words, when the air pressure within the support airbag 311 exceeds half, the stiffness of the support airbag 311 is sufficient to effectively support the back support plate 312. At this point, the magnetic valve opens, allowing air to enter the clamping airbag 33 and the lifting airbag 322 through the internal passage, squeezing, clamping, and lifting the patient's torso and buttocks.

[0036] In this embodiment, the inflation of the support airbag 311 is completed by an air pump. The air pump is located in the box body and is communicated with the main controller 6. The first conduit connected to the air pump is opened in the base plate body 1; the support airbag 311 lifts the back support plate 312 during the inflation process, and the back support plate 312 gradually changes from an inclined state to a horizontal state. At the same time, the piston rod drives the piston head to move from bottom to top in the cylinder 341, and the resistance coil 343 gradually rises. The length of the resistance coil 343 in the access circuit in contact with the wire gradually decreases, so that the current field passing into the sac 313 containing electrorheological fluid gradually increases. In the process of the patient's torso changing from a downward tilt to a horizontal state, the electrorheological fluid gradually changes from a liquid state to a solid state, so that the sac 313 containing electrorheological fluid is formed into a mold shape that is compatible with the patient's back.

[0037] Furthermore, as the patient's torso transitions from a downward tilt to a horizontal position, since their lower limbs are fixed, they can only achieve horizontality by shifting their upper body backward. This shift brings their shoulder blades closer to pressure sensor 224. When the pressure value on pressure sensor 224 reaches the set value (i.e., the pressure value applied to pressure sensor 224 during initial positioning), pressure sensor 224 sends a signal to main controller 6, which in turn instructs the inflation pump to stop inflating support airbag 311. At this point, due to the transition in the electrorheological fluid's state and its tight engagement with the patient's back, the clamping airbags 33 on either side squeeze and clamp the patient's torso, while the supporting airbags 322 squeeze and support the patient's buttocks. Calibration of the initial position and pressure value ensures that the patient's position is maintained throughout each chemotherapy session, ensuring accurate positioning regardless of changes in the patient's body shape.

[0038] Example 3: On the basis of the above-mentioned embodiment 1 and embodiment 2, in order to further fix the patient's torso to prevent the patient's upper body from swinging during radiotherapy and to reduce the impact of breathing on chest fluctuations, the following further improvements are made to the torso wrapping and fixing mechanism 4.

[0039] like Figure 10-13 As shown, the torso wrapping and fixing mechanism 4 includes a thermoplastic wrapping component 41 and a restraint component 42. When not in use, the thermoplastic wrapping component 41 is located on one side of the mold forming mechanism 3 (similar to a plastic wrap here). When in use, the thermoplastic wrapping component 41 is wrapped around the patient's torso after thermoplastic deformation. The restraint component 42 is movably connected to the base plate body 1, and the restraint component 42 is slidably set at the rear end of the thermoplastic wrapping component 41.

[0040] Specifically, the thermoplastic wrapping assembly 41 includes a winding shaft 411, a thermoplastic film 412 and a resistance wire 413. The winding shaft 411 is movably connected to the inside of one side of the back support plate 312. The thermoplastic film 412 is wound on the winding shaft 411. The thermoplastic film 412 is provided with a number of ventilation holes. The resistance wire 413 is arranged along the axial direction of the winding shaft 411. When in use, the knob switch is rotated to connect the circuit of the resistance wire 413. When the resistance wire 413 is energized and heated, the thermoplastic film 412 changes from a hard material to a soft material. The doctor pulls out the free end of the thermoplastic film 412, passes it around the top of the patient's torso, and then fixes it to the other side of the back support plate 312.

[0041] Furthermore, the restraint assembly 42 includes an elastic fixing belt 421 and a buckle 422. Two buckles 422 are provided and are respectively slidably connected to the slide grooves on both sides of the base body 1. One end of the elastic fixing belt 421 is connected to one of the buckles 422. After the two buckles 422 are slid to the appropriate position, the other end of the elastic fixing belt 421 is inserted into the corresponding buckle 422 to restrain the tail end of the thermoplastic film 412 to the patient's abdomen.

[0042] Thermoplastic film 412 is a polymer material that is hard and sheet-like at room temperature. It softens upon heating and can be shaped to the patient's body contours, hardening into its original form upon cooling at room temperature. Thermoplastic film 412 is applied to different areas of the body in different forms. The two commonly used "head and shoulder wraps" and "body wraps" can meet the needs of most patients. The former is primarily used for fixation of the head, neck, and shoulders; the latter is mostly used for fixation of the chest, abdomen, pelvis, and other areas, with a few also used for lower limbs. Although thermoplastic film 412 must be heated to 60-70°C to soften, once removed from the water tank or oven and exposed to the air, its temperature drops significantly, approaching body temperature. Currently, few patients report experiencing unbearable temperatures.

[0043] Example 4: A tumor radiotherapy positioning and fixation device, when used in clinical radiotherapy: First, the patient lies on the bladder 313 containing electrorheological fluid, with their head resting on the pillow 21. Due to the patient's own weight, the back support plate 312 rotates around the rotation axis, tilting the bladder 313 containing electrorheological fluid downward. At this point, the patient's thigh is secured to the arched support block 511 using a first elastic restraint belt, and the patient's foot is secured to the ankle joint placement slot 521 using a second elastic restraint belt 522. At this time, the patient's body is in a V shape as a whole (i.e., high at both ends and low in the middle). The main controller 6 turns on the air pump, and the gas enters the support airbag 311 through the catheter. The gas in the support airbag 311 gradually increases and the pressure increases. The support body bag pushes the back support plate 312 to gradually change from an inclined state to a horizontal state. When the air pressure value in the support airbag 311 exceeds 1 / 2 of the pressure value when the support airbag 311 is full (the set pressure value), the feedback information is sent to the main controller 6, and the main controller 6 opens the magnetic valve between the support airbag 311 and the clamping airbag 33 and the lifting airbag 322. The gas in the support airbag 311 gradually enters the clamping airbag 33 and the lifting airbag 322, respectively clamping the two sides of the patient's torso and the lower end of the buttocks; During this process, the piston rod drives the piston head upward, and the resistance coil 343 moves upward accordingly. The resistance coil 343 in contact with the wire gradually becomes shorter, which reduces the resistance in the connected circuit and increases the current field in the area where the electrorheological fluid is located. The electrorheological fluid gradually changes from liquid to solid to match the patient's back shape, thus completing personalized molding according to the patient's body shape. Moreover, during the lifting process of the back support plate 312, since the patient's lower limbs are fixed, this movement can only be completed by moving the patient's torso forward. The patient's shoulder blade gradually approaches the second pressure sensor 224. When the pressure value of the second pressure sensor 224 reaches the set threshold, the signal is fed back to the main controller 6, and the main controller 6 controls the air pump to stop working. At this point, through the calibration of position and pressure values, the same position model is completed for the patient under the condition of body shape changes, ensuring the accuracy of radiotherapy positioning; Then, the control knob is rotated to heat the thermoplastic film 412 with the resistance wire 413 to soften it. The thermoplastic film 412 is pulled out and passed over the patient's torso. The end of the thermoplastic film 412 is fixed to the back support plate 312. The elastic fixing belt 421 and the buckle 422 are used to fix the end of the thermoplastic film 412 close to the patient's abdomen. The pulling hook 223 is used to pull the front end of the thermoplastic film 412 so that the front end of the thermoplastic film 412 is tightly attached to the patient's chest. Finally, during radiotherapy, the patient raises both hands above his head to grasp the gripping rod, and the patient's gripping strength is fed back through the pressure sensor 71, and the pressure value is fed back to the main controller 6 and displayed on the electronic display screen. The doctor can judge the patient's physical and psychological state during radiotherapy by the pressure value.

[0044] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the foregoing embodiments. The foregoing embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A positioning and fixing device for tumor radiotherapy, comprising a base plate body (1), characterized in that: The top of the bottom plate body (1) is provided with: A headrest calibration mechanism (2) corresponds to the position of the patient's head in a supine position, and the patient's position is determined by the pressure value of the headrest calibration mechanism (2); The mold forming mechanism (3) is arranged adjacent to the headrest calibration mechanism (2) and performs adaptive molding according to the patient's body shape changes at different stages of radiotherapy; A trunk wrapping and fixing mechanism (4) is arranged above the mold forming mechanism (3) and is used to wrap and fix the patient's trunk during radiotherapy; A lower limb limiting mechanism (5) is arranged at one end of the mold forming mechanism (3) close to the tail; A main controller (6) is arranged at the rear end of the lower limb limiting mechanism (5), and the main controller (6) is communicatively connected with the headrest calibration mechanism (2), the mold forming mechanism (3), and the trunk wrapping and fixing mechanism (4).

2. The tumor radiotherapy positioning and fixation device according to claim 1, characterized in that: The mold forming mechanism (3) includes: A body support assembly (31) is movably connected to the headrest calibration mechanism (2); A hip lifting component (32) is provided at the rear end of the body supporting component (31), and a variable resistance component (34) is provided at the bottom of the hip lifting component (32), and the current in the body supporting component (31) is regulated by the variable resistance component (34); Two clamping airbags (33) are provided and are both located on both sides of the body support component (31).

3. The tumor radiotherapy positioning and fixation device according to claim 2, characterized in that: The body support assembly (31) comprises: A supporting airbag (311) is connected to the base plate body (1), and the supporting airbag (311) has an arched structure when inflated; The back support plate (312) is located on the top of the support airbag (311), and a capsule (313) containing electrorheological fluid is provided on the top of the back support plate (312).

4. The tumor radiotherapy positioning and fixation device according to claim 3, characterized in that: The hip lifting assembly (32) includes: A buttocks support plate (321) is provided at the rear end of the back support plate (312), and the middle portion of the buttocks support plate (321) is concave; The lifting airbag (322) is arranged on the inner side of the edge of the hip support plate (321).

5. The tumor radiotherapy positioning and fixation device according to claim 3, characterized in that: The variable resistance component (34) comprises: A cylinder (341) is arranged on the top of the bottom plate body (1); A piston member (342) is connected to the bottom of the buttocks support plate (321) and is movably inserted into the cylinder (341); The resistance coil (343) is wound around the piston member (342), and is connected to the capsule (313) containing the electrorheological fluid via a wire passing through the cylinder (341).

6. The tumor radiotherapy positioning and fixation device according to claim 1, characterized in that: The trunk wrapping fixing mechanism (4) comprises: A thermoplastic wrapping component (41) is located on one side of the mold forming mechanism (3) when not in use and is wrapped around the patient's torso after being thermoplastically deformed when in use; The restraining component (42) is movably connected to the base plate body (1) and is located at the rear end of the thermoplastic wrapping component (41).

7. The tumor radiotherapy positioning and fixation device according to claim 6, characterized in that: The thermoplastic wrap assembly (41) includes: A winding shaft (411) is provided on one side of the mold forming mechanism (3); The thermoplastic film (412) is wound on the winding shaft (411), and in the use state, the free end of the thermoplastic film (412) is passed over the upper part of the patient's torso and then fixed to the other side of the mold forming mechanism (3); The resistance wire (413) is arranged along the axial direction of the winding shaft (411). When the resistance wire (413) is energized and heated, the thermoplastic film (412) changes from hard to soft.

8. The tumor radiotherapy positioning and fixation device according to claim 1, characterized in that: The headrest calibration mechanism (2) includes: A pillow member (21) is connected to the base plate body (1), and a supporting plate (8) connected to the mold forming mechanism (3) is provided at the rear end of the pillow member (21); The pressure calibration component (22) is arranged on both sides of the pillow component (21), and the pressure value of the patient's shoulder is fed back through the pressure calibration component (22), thereby achieving unified positioning of the patient's radiotherapy position.

9. The tumor radiotherapy positioning and fixation device according to claim 8, characterized in that: It also includes a gripping mechanism (7) arranged at the head end of the base plate body (1), and a pressure measuring structure for feeding back the gripping strength of the patient is arranged on the gripping mechanism (7).

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