Optimized multi-leaf beam collimator device

Abstract

The invention provides an optimized multi-leaf beam collimator capable of being used for a medical linear accelerator, and relates to the field of medical physics. On the basis of a traditional multi-leaf beam collimator, the device is coupled with a polypropylene plastic fence and tungsten alloy particles, and the polypropylene plastic fence and the tungsten alloy particles are used for filling gaps behind a conformal target region of the multi-leaf collimator, so that the phenomenon of leakage emission or underemission in the radiotherapy process is avoided, and the purpose of precise radiotherapy is achieved. Wherein the polypropylene shaping fence has considerable thermoplasticity, and an accurate X-ray channel conforming to a target area can be shaped according to the outline of the target area by controlling the temperature (the thermal deformation temperature is about 150 DEG C); each tungsten alloy particle is composed of 95% of tungsten, 3.5% of nickel and 1.5% of copper, is in the shape of a solid ball with the diameter of 0.1 mm, and is used for filling a gap between the multi-leaf collimator and the polypropylene plastic fence. According to the design, the accuracy of radiotherapy is remarkably improved, and a safer and more effective treatment scheme is provided for a patient.

Description

Technical Field

[0001] The present invention relates to the field of medical physics, and specifically to an optimized multi-leaf beam collimator device. Background Art

[0002] With the continuous progress of global medical technology and the growth of medical needs, the treatment methods for tumor diseases have been greatly developed. Among them, radiotherapy, as one of the important means of tumor treatment, has been increasingly widely used clinically. The medical linear accelerator, as a key device for radiotherapy, is of great importance. The medical linear accelerator is a product for clinical radiotherapy with conventional X-rays or electron beams, and is composed of components such as a treatment head, an accelerating tube, a magnetron / klystron, a collimator, a positioning system, a treatment couch, a control system, a modulator, and a water cooling unit. Among them, the relatively core component is the collimator. The medical linear accelerator is generally equipped with a multi-leaf collimator, which is composed of multiple small tungsten leaves that can be independently operated. These leaves can be flexibly combined to construct an X-ray channel that fits the shape of the tumor.

[0003] However, the multi-leaf collimator has inherent limitations when constructing a radiation field that conforms to the shape of the target area. The boundary of the formed radiation field is often serrated and not smooth enough, which may lead to insufficient dose received by the target area or unnecessary additional radiation to the surrounding healthy tissues. To overcome this challenge, improve the accuracy and effectiveness of radiotherapy, and better protect the healthy tissues of patients, we propose an optimized multi-leaf beam collimator device, which is based on the traditional multi-leaf beam collimator and is coupled with a polypropylene plastic enclosure and tungsten alloy particles.

[0004] This optimized multi-leaf beam collimator device can quickly and accurately construct an X-ray channel of any shape, forming a desired radiation field that highly conforms to the shape of the target area. This innovative technology not only improves the accuracy of radiotherapy, but also injects new vitality into the development of the radiotherapy field. Summary of the Invention

[0005] In order to perform radiotherapy more efficiently and safely, the present invention provides an optimized multi-leaf beam collimator device. It consists of three parts: a traditional multi-leaf collimator, a polypropylene plastic enclosure, and tungsten alloy particles.

[0006] The optimized multi-leaf beam collimator device is specifically composed of three parts: a traditional multi-leaf collimator, a polypropylene plastic enclosure, and tungsten alloy particles. The traditional multi-leaf collimator consists of 26 pairs of blades with a width of 10 mm, and its maximum field of view is 26×40 cm. The plastic enclosure is made of polypropylene material, and its critical softening temperature is about 150 °C. After heating and shaping, polypropylene has high strength, excellent fatigue resistance, and stable chemical properties, and is non-toxic and reusable; using the thermoplasticity and high hardness of polypropylene material, an X-ray channel with a precise conformal target area can be quickly constructed. A single tungsten alloy particle is composed of 95% tungsten, 3.5% nickel, and 1.5% copper, and its geometric shape is a solid sphere with a diameter of 0.1 mm. This material has excellent shielding performance for rays; after the traditional multi-leaf collimator and the polypropylene plastic enclosure are conformal to the target area, due to the inherent serrated boundary of the multi-leaf collimator, there are multiple gaps between the two. Therefore, using a large number of the above-mentioned tungsten alloy particles to fill these gaps can avoid the situation of insufficient target area dose or increasing the patient's additional dose, and achieve a safer and more efficient radiotherapy.

[0007] Figure 2 The effects of the traditional multi-leaf collimator and the optimized multi-leaf collimator device of the present invention during conformal target area were compared. The results showed that the device of the present invention can construct the desired field of view of the conformal target area, accurately match the planned target volume, effectively avoid the leakage or under-irradiation of X-rays, and greatly improve the accuracy and safety of radiotherapy. Description of the Drawings

[0008] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification for explaining the present invention, and do not constitute a limitation to the present invention.

[0009] Figure 1 Schematic diagram of an optimized multi-leaf beam collimator device of the present invention;

[0010] Figure 2 Effect comparison diagram of the optimized multi-leaf collimator and the traditional multi-leaf collimator of the present invention; Detailed Embodiments

[0011] 1. The radiotherapy plan is jointly formulated by a physician and a physicist. Subsequently, we accurately depict the contour of the planned target volume (PTV) based on this, fit the contour information to record the fitting function, and place the traditional multi-leaf collimator in the planned position.

[0012] 2. Combining the above fitting function with the injection molding technology, the computer control system can quickly and accurately construct the preset polypropylene plastic enclosure, which is hollow inside and has a smooth contour consistent with the desired field of view of the boundary. The polypropylene plastic enclosure and the in-place multi-leaf collimator jointly form a "ray leakage channel", laying a foundation for filling the ray shielding material subsequently.

[0013] 3. In the gap between the constructed polypropylene enclosure and the multi-leaf collimator, we injected a large amount of tungsten alloy particles described in this article, so that it can effectively shield X-rays and ensure the safety of the treatment process.

[0014] 4. When X-rays pass through the hollow channel formed inside the polypropylene enclosure, they can produce a precise radiation field in the predetermined target area, thereby achieving the desired treatment effect.

[0015] 5. Using the optimized multi-leaf beam collimator device, we can quickly generate multiple required sub-fields at different fixed angles. These sub-fields are superimposed after step-by-step irradiation to form an ideal dose distribution, which can achieve more precise radiotherapy.

Claims

1. An optimized multi-leaf beam collimator device, characterized in that: (a) Based on the traditional multi-leaf beam collimator, this device is coupled with a polypropylene plastic enclosure and tungsten alloy particles, which are used to fill the gaps after the multi-leaf collimator conforms to the target area, so as to avoid leakage or underdose during radiotherapy and achieve the purpose of precise radiotherapy; (b) The polypropylene plastic enclosure has considerable thermoplasticity. According to the target area contour and by controlling the temperature (the heat distortion temperature is about 150 °C), an X-ray channel that precisely conforms to the target area can be shaped; (c) Each tungsten alloy particle is composed of 95% tungsten, 3.5% nickel and 1.5% copper, and its shape is a solid sphere with a diameter of 0.1 mm, which is used to fill the gaps between the multi-leaf collimator and the polypropylene plastic enclosure. This design significantly improves the precision of radiotherapy and provides a safer and more effective treatment plan for patients.

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