Body surface positioning device for radiation interventional therapy

Abstract

The invention discloses a body surface positioning device for radiation interventional therapy, and belongs to the technical field of medical equipment in the radiology department. The device comprises a fixing frame and an elastic cushion arranged on the inner side of the fixing frame, a through hole, a pouring inner cavity and a fixing belt structure are arranged in the elastic cushion, and the elastic cushion is filled with liquid filler capable of being rapidly solidified. The filler is preferably gypsum filling liquid and is prepared from alpha-high-strength gypsum powder, a coagulation accelerator, a thermal buffer agent, toughening fibers and blending liquid in proportion. Slurry is injected through the liquid injection pipe, exhausted through the air outlet valve and solidified to form a rigid mold tightly attached to the body surface of a patient, and accurate positioning is achieved. The device is easy and convenient to operate, controllable in curing temperature rise, good in air permeability, capable of effectively avoiding thermal injury and improving the comfort level and body position repeatability of a patient, and suitable for radiation interventional therapy of different parts such as the head and the chest and abdomen.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of radiology medical equipment, in particular to a body surface positioning device for radiotherapy. BACKGROUND

[0002] Radiotherapy and interventional therapy are important means for treating tumors and other diseases, and their efficacy is highly dependent on accurate positioning during treatment. Due to the autonomous or involuntary movements of the human body such as respiration and peristalsis, the body contour and internal target position will change, in order to ensure the high repeatability of the body position during each treatment, the patient must be effectively fixed on the body surface. Therefore, the body surface positioning device has become an indispensable key equipment in modern precision radiotherapy.

[0003] The body position fixing technology widely used in clinical at present is mainly thermoplastic film, as shown in the following figure. Figure 1 The thermoplastic film is a mesh plate made of high molecular polyester material, which is softened after heating in 60-70℃ hot water, can be stretched and covered on the patient's body surface, and becomes hard again after cooling, forming an individualized fixed mold that fits the patient's body surface contour. However, this technology has several inherent defects: first, the risk of thermal injury, as the operation needs to be softened at high temperature, even if the operator waits for its temperature to drop slightly, for children, skin sensitive or emaciated patients, there is still a risk of scalding when directly applied to the skin, the root cause lies in the uncontrollable cooling process and the direct heat transfer to the skin; second, the operation is complicated and depends on experience, the whole process of heating, transferring, stretching and shaping needs to be completed in a very short time, which requires high technical proficiency of the operator, uneven stretching force will cause local excessive pressure or poor fixation, and the patient is easy to move due to the feeling of stuffiness and oppression during the process, affecting the molding precision; third, poor air permeability and comfort, although the material is mesh, the overall covered area is still airtight, the patient is easy to sweat when the treatment time is long, which leads to skin immersion and itching, at the same time, the hard film body after cooling produces continuous and uneven pressure points on the convex parts of the body surface (such as ribs and iliac bones), which is poor in comfort; fourth, deformation caused by repeated use, the thermoplastic film can be reused for several times, but the material will be stretched and tired after many heating and cooling cycles, which makes it gradually relax and reduces the fitting precision with the patient's contour, affecting the repeatability of fixation. Therefore, there is an urgent need in clinical for a new type of body surface positioning technology and device that can overcome the above defects and realize comfort, precision, safety and simple operation. SUMMARY

[0004] (I) Technical problems solved In view of the deficiencies of the prior art, the present application provides a body surface positioning device for radiotherapy, which solves the problems raised in the background art.

[0005] Technical scheme In order to achieve the above object, the present application is realized by the following technical scheme: A body surface positioning device for radiotherapy intervention treatment, comprising a fixed frame, a plurality of through holes are arranged in the fixed frame, a pouring cavity is arranged in the fixed frame, the fixed frame is divided into a plurality of fixed belts by the through holes, and a quick solidification liquid filler is filled in the fixed frame.

[0006] Preferably, the longitudinal section of the fixed frame is a convex letter shape without a bottom, so that the fixed frame is staggered with the shoulder of the patient.

[0007] Preferably, the two ends of the elastic pad are fixedly connected with liquid injection pipes, the liquid injection pipes are communicated with the pouring cavity, and the liquid filler enters the pouring cavity through the liquid injection pipes.

[0008] Preferably, the upper side wall of the elastic pad is fixedly connected with a plurality of air outlet valves, the air outlet valves are communicated with the pouring cavity, and the gas in the pouring cavity is discharged.

[0009] Preferably, a plurality of fixed sleeves are fixedly connected in the fixed frame, and a fixing screw rod for fixing the fixed frame to a treatment bed is threadedly connected in each fixed sleeve.

[0010] Preferably, the quick solidification liquid filler is a gypsum filling liquid.

[0011] Preferably, the gypsum filling liquid is prepared by mixing the following raw materials in parts by weight: 100 parts of α-high strength gypsum powder, 0.5-1.5 parts of setting accelerator, 3-8 parts of thermal buffer, 1-3 parts of toughening fiber, and 35-45 parts of blending liquid.

[0012] Preferably, the configuration method of the gypsum filling liquid comprises S1, dry powder pre-mixing, α-high strength gypsum powder, setting accelerator potassium sulfate, thermal buffer phase change microcapsule and toughening PVA fiber are weighed according to the proportion, placed in a dry container and stirred at low speed for 5-10 minutes until uniformly mixed; S2, mixing and grouting, a specified proportion of blending liquid is measured, the mixed dry powder is slowly poured into the container containing the blending liquid, and after standing for 30-60 seconds, an electric mixer is used to stir at a speed of 800-1200 revolutions per minute for 60-90 seconds to obtain a uniform and particle-free gypsum slurry; S3, immediate use, the prepared slurry is quickly sucked into a syringe, and injected into the device within its operating time.

[0013] A use method of a body surface positioning device for radiotherapy intervention treatment is applied to the above-mentioned body surface positioning device for radiotherapy intervention treatment, and characterized in that it comprises the following steps: S1, before operation, place the device on a radiotherapy bed or interventional operating table, roughly position according to the treatment site, guide the patient to lie on the treatment bed or interventional operating table, and place the patient's head on the headrest part of the treatment bed or interventional operating table; S2, inject the filling liquid, connect the pre-prepared quick solidification liquid filling to the injection pipe through the syringe, and inject uniformly into the pouring cavity until the filling liquid overflows from the opposite injection pipe or the air outlet valve, indicating that the cavity is filled; S3, preliminary fixation, by rotating the fixing screw, the fixing frame is fixed relative to the treatment bed, and the patient's body position is preliminarily constrained; S4, solidification and shaping, keep the patient's body position unchanged, and the liquid filling in the pouring cavity occurs solidification reaction, and after the solidification is completed, the elastic pad is closely attached to the patient's body surface contour, forming a rigid fixed mold; S5: treatment implementation, image scanning and ray irradiation during radiotherapy; S6: postoperative removal, after the treatment is completed, the fixing screw is loosened, and the device is taken off from the patient's body as a whole.

[0014] (Three) beneficial effects The application provides a body surface positioning device for radiotherapy, which has the following beneficial effects: 1, the application adopts low-temperature solidification gypsum filling liquid with built-in phase change microcapsules, and the contact temperature of the solidification exothermic peak is controlled near 37.5 DEG C through the heat absorption effect, which completely avoids the risk of scalding caused by the high-temperature softening of traditional thermoplastic film. The system does not need heating and waiting for cooling, and can be directly injected and formed, which is safe and simple to operate, especially suitable for children, the elderly or patients with sensitive skin, which can significantly improve the safety of the treatment process while realizing accurate fixation.

[0015] 2, significantly improve comfort and air permeability, suitable for long-term positioning. The elastic pad is provided with a uniform distribution of through hole structure, and the air on the patient's body surface can flow freely during the treatment process, effectively reducing the accumulation of sweat and the feeling of stuffiness. At the same time, the rigid support after solidification is combined with the elastic material, which avoids the local compression of the traditional hard fixed film on the protruding part of the skeleton, and the distribution is more uniform and soft, thereby greatly improving the tolerance and comfort of the patient during the long-term radiotherapy.

[0016] 3, simple and fast operation, accurate forming and one-time use. The device is formed by injection perfusion, which does not need to rely on the proficiency of the operator, reduces the fixed deviation caused by uneven stretching of the human body. The formula of the gypsum filling liquid is controllable, the operation time is clear, and the individualized mold closely combined with the patient's body surface is formed after solidification, the repeated positioning error is less than 1mm, and the device is disposable, which eliminates the deformation and precision decline problem caused by repeated use. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 This is a schematic diagram of a thermoplastic film based on existing technology. Figure 2 This is a schematic diagram of the structure of the present invention; Figure 3 This is a front view of the present invention; Figure 4 This is a side view of the present invention; Figure 5 This is a schematic diagram of the internal structure of the present invention; Figure 6 This is a schematic diagram of Embodiment 2 of the present invention.

[0018] Among them, 1. fixed frame; 2. elastic pad; 201. through hole; 202. liquid injection tube; 203. air outlet valve; 204. casting cavity; 205. fixing strap; 3. fixing sleeve; 301. fixing screw; 4. thermoplastic film. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1: like Figures 2-5 As shown, this embodiment of the invention provides a surface positioning device for interventional radiotherapy, specifically designed for stereotactic body radiotherapy (SBRT) of the head. This embodiment provides a surface positioning device specifically for SBRT of the head.

[0021] The fixation frame 1 is made of carbon fiber composite material, which is characterized by high strength, light weight, and extremely low radiation interference. Its shape is a U-shaped structure adapted to a standard headrest, approximately 25cm wide and 15cm high, with a bottomless convex cross-section, effectively avoiding pressure on the patient's ears and temples. The elastic pad 2 is made of medical-grade silicone with a Shore A hardness of 30, approximately 2.5cm thick, and is completely adhered to the inner contour of the fixation frame 1 using a biocompatible adhesive. Through-holes 201 are densely and evenly distributed throughout the elastic pad, with a pore diameter of approximately 1cm, dividing it into numerous small fixation bands 205. This allows the elastic pad to softly wrap around the irregular contours of the head, much like a memory foam. The casting cavity 204 is a pre-formed three-dimensional mesh channel system within the silicone pad, with main channels approximately 6mm in diameter and branch channels approximately 3mm in diameter, ensuring that the slurry can quickly fill all corners.

[0022] The infusion tube 202 consists of two medical-grade PP Luer connectors, which are respectively embedded in the corresponding temple positions on the left and right sides of the elastic pad. The vent valve 203 consists of three one-way vent valves distributed on the forehead and parietal bone to ensure complete venting. There are four fixing sleeves 3, which are brass internally threaded sleeves embedded in the bottom of the fixing frame. The matching fixing screws 301 can be screwed into the positioning holes of the treatment bed.

[0023] The usage method of this embodiment is as follows: Preoperative preparation and fixation: Place the device on the headrest of the treatment bed, tighten the fixing screw 301 to initially fix it, guide the patient to lie supine, and comfortably place the back of the head and neck on the soft elastic pad 2. Preparation of a special gypsum filler solution: Take 100 parts by weight of α-high-strength gypsum powder, 1.2 parts by weight of potassium sulfate accelerator, 6 parts by weight of phase change microcapsule heat buffer, and 1.5 parts by weight of PVA fiber toughening agent, and mix them in a vacuum mixer at 250 rpm for 10 minutes to ensure absolute uniformity and no lumps. Measure 38 parts by weight of sterile ice-pure water at 4°C to further control the initial reaction temperature. Slowly pour the mixed dry powder into the ice water, let it stand for 40 seconds, and then stir at a high speed of 1200 rpm for 60 seconds to obtain a fine slurry with excellent flowability. The entire process must be completed within 4 minutes. Injection and Curing: Immediately draw up the slurry using a large-diameter syringe, connect it to one injection tube 202, and inject it at a constant rate. The slurry quickly fills the mesh casting cavity 204, and air is evenly expelled from the vent valve 203. When slurry overflows from the other injection tube, immediately seal all interfaces with a plug. The patient remains still, and the plaster cures within 7 minutes. During the curing process, the phase change microcapsules effectively absorb the heat of hydration reaction, keeping the maximum temperature of the elastic pad surface in contact with the skin stable at 37.5℃. The patient only feels a mild warmth, with no risk of burns.

[0024] Treatment and Results: After curing, the originally soft elastic pad 2, together with the plaster inside the silicone, forms a rigid mold that closely conforms to the patient's head and neck anatomy, including the occipital protuberance, auricle, and mandibular angle, resulting in precise and stable fixation. During CT simulation localization and subsequent radiotherapy, the repeatability error is less than 1 mm. After treatment, the entire device can be easily removed by loosening the fixing screw 301.

[0025] Example 2: Positioning device for chest and abdominal radiotherapy like Figure 6 As shown, the difference between this embodiment and Embodiment 1 is that this device is specifically designed for large-area radiotherapy of the chest and abdomen.

[0026] The fixed frame 1 consists of two parallel rods, with increased dimensions (approximately 70cm long, 50cm wide, and 12cm high), made of medical-grade ABS plastic. This design ensures sufficient support strength while reducing costs. The elastic pad 2 is made of TPU thermoplastic polyurethane with a Shore A hardness of 50 and a thickness of 2cm to provide better support. The pore diameter of the through-hole 201 is increased to 2cm to further improve breathability and reduce patient discomfort from sweating during prolonged treatment. The mesh channel backbone of the casting cavity 204 is thicker to ensure that the slurry can quickly cover a large area.

[0027] The formula for the gypsum filler solution has been adjusted to: 100 parts α-high-strength gypsum powder, 0.8 parts potassium sulfate, 4 parts phase change microcapsules, 2 parts PVA fiber, and 42 parts room temperature pure water. This formulation extends the operation time to approximately 6 minutes, making it more suitable for larger-volume perfusion procedures in the chest and abdomen. Furthermore, it provides higher overall strength after curing to support the weight of the torso.

[0028] The method of use is similar to that in Example 1, but its unique effect is: After the patient lies supine on the device, the frame is initially fixed, and then the slurry is injected. The mold formed after solidification can accurately replicate the patient's chest rise and fall, abdominal contours, and even umbilical indentation.

[0029] The densely packed 201 perforated structure allows the patient's back skin to "breathe" freely, greatly improving comfort during long treatment sessions and avoiding the stuffiness and sweat buildup caused by traditional vacuum pads or thermoplastic films.

[0030] The rigid connection between the fixed screw 301 and the treatment bed ensures a high degree of repeatability of the patient's position during each treatment, effectively reducing treatment errors caused by differences in position.

[0031] Example 3: Based on Embodiment 1 or 2, this embodiment makes targeted improvements to the material and surface structure of the elastic pad 2, aiming to further enhance the patient's immediate comfort, solve the compatibility problem for patients with sensitive skin, and enhance the hygiene and cleaning efficiency of the device.

[0032] The elastic pad 2 in this embodiment employs a double-layer composite structure. Its main base layer is still made of medical-grade silicone or soft TPU to ensure structural support and deformation capacity. The key improvement lies in the permanent lamination of a hydrophilic medical-grade silicone gel layer onto the inner wall of the elastic pad (i.e., the side in direct contact with the patient's skin). This silicone gel layer is approximately 2-3 mm thick, and its material properties are similar to those of top-tier burn dressings or breast prosthesis contact layers on the market, exhibiting excellent softness, viscoelasticity, and biocompatibility.

[0033] To further improve hygiene, a disposable, highly permeable nonwoven fabric liner can also be provided. In use, the liner is placed over the silicone gel layer before the patient lies down. After the injection solidifies, the liner embeds into the molded surface. After treatment, the liner is simply removed and discarded, achieving "one liner per patient," eliminating the need for cleaning steps, and is particularly suitable for cases with poor skin condition or requiring strict isolation.

[0034] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A surface positioning device for interventional radiology, comprising a fixing frame (1), characterized in that: The fixed frame (1) is provided with an elastic pad (2) fixedly connected inside. The elastic pad (2) is provided with several through holes (201) inside. The elastic pad (2) is provided with a casting cavity (204) inside. The elastic pad (2) is divided into several fixing bands (205) by the through holes (201). The elastic pad (2) is filled with a fast-curing liquid filler.

2. The body surface positioning device for interventional radiotherapy according to claim 1, characterized in that: The longitudinal section of the fixed frame (1) is a bottomless convex shape.

3. The body surface positioning device for interventional radiotherapy according to claim 1, characterized in that: Both ends of the elastic pad (2) are fixedly connected to injection pipes (202), and the injection pipes (202) are connected to the casting cavity (204).

4. The body surface positioning device for interventional radiotherapy according to claim 1, characterized in that: The upper side wall of the elastic pad (2) is fixedly connected with several air vent valves (203), and the air vent valves (203) are connected to the casting cavity (204).

5. The body surface positioning device for interventional radiotherapy according to claim 1, characterized in that: The fixed frame (1) is uniformly fixedly connected with a number of fixed sleeves (3), and each fixed sleeve (3) is threadedly connected with a fixing screw (301) for fixing the fixed frame (1) to the treatment bed.

6. The body surface positioning device for interventional radiotherapy according to claim 1, characterized in that: The rapidly curing liquid filler is a gypsum filler liquid.

7. A surface positioning device for interventional radiotherapy according to claim 6, characterized in that, The gypsum filler liquid is prepared by mixing the following raw materials in parts by weight: 100 parts α-high strength gypsum powder, 0.5-1.5 parts coagulant, 3-8 parts heat buffer, 1-3 parts toughening fiber, and 35-45 parts mixing liquid.

8. The body surface positioning device for interventional radiotherapy according to claim 7, characterized in that: The coagulant is potassium sulfate, the heat buffer is phase change microcapsules, the toughening fiber is PVA fiber, and the mixing solution is pure water or boric acid aqueous solution.

9. A body surface positioning device for interventional radiotherapy according to claim 8, characterized in that, The method for preparing the plaster filler liquid includes the following steps: S1. Dry powder premixing: Weigh out α-high-strength gypsum powder, potassium sulfate accelerator, phase change microcapsules heat buffer and toughening PVA fiber according to the proportion, place them in a dry container and stir at low speed for 5-10 minutes until they are mixed evenly. S2. Mixing and preparing the slurry: Measure the specified proportion of the mixing liquid, slowly pour the mixed dry powder into the container containing the mixing liquid, let it stand and soak for 30-60 seconds, then use an electric mixer to stir at a speed of 800-1200 rpm for 60-90 seconds to obtain a uniform gypsum slurry without particles. S3. Use immediately: Quickly draw the prepared slurry into the syringe and inject it into the device within its operating time.

10. A method of using a surface positioning device for interventional radiology, applied to any one of the surface positioning devices for interventional radiology as described in claims 1-9, characterized in that, Includes the following steps: S1. Preoperative preparation: Place the device on the radiotherapy bed or interventional operating table, roughly locate it according to the treatment site, guide the patient to lie on the treatment bed or interventional operating table, and place the patient's head on the headrest of the treatment bed or interventional operating table. S2. Inject filling liquid. Connect the pre-mixed fast-curing liquid filler to the injection tube (202) through a syringe and inject it into the casting cavity (204) at a uniform speed until the filler overflows from the opposite injection tube or the vent valve (203), indicating that the cavity has been filled. S3. Initial fixation: By tightening the fixing screw (301), the fixing frame (1) is fixed relative to the treatment bed, and the patient's position is initially constrained; S4. Solidify and shape, keep the patient in a fixed position, and the liquid filler undergoes a solidification reaction in the casting cavity (204). After solidification, the elastic pad (2) fits tightly against the contour of the patient's body surface to form a rigid fixed mold. S5. Treatment implementation: Imaging scans and radiation exposure during interventional radiology treatment; S6. Postoperative removal: After the treatment is completed, loosen the fixing screw (301) and remove the entire device from the patient.

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