THE POSSIBILITY INVESTIGATION OF THE MEDICAL ELECTRON BEAM SHAPING USING DEVICES MADE FROM PLASTICS WITH METAL IMPURITIES

In modern practice, collimators are employed in electron beam therapy to shape the radiation field into standard configurations. However, tumors often exhibit complex shapes, necessitating collimators with individually created collimation windows, typically made of metal alloys. The production of such devices is time-consuming, limiting their widespread use. A promising approach to collimator manufacturing lies in three-dimensional printing, using a fused filament fabrication that makes it possible to produce three-dimensional objects quick and accurate. Presently, the polymer materials used allow for 3D printing products with a density of up to 1.3 g/cm³, which leads the necessity to manufacture a collimator of relatively large thickness. This study proposes the utilization of plastics infused with metal impurities for 3D printing collimators created for the electron beam therapy. Numerical simulations were conducted using the Monte Carlo method to calculate the requisite collimator thickness for effective absorption of electron beams therapeutic energies range. Consequently, a modular collimator was designed and 3D printed, offering the flexibility to vary the diameter of the collimation window from 0.5 to 6 cm. Based on the experimental data obtained for the medical electron beam with an energy of 6 MeV, it was defined that the 3D printed device can effectively shaped a radiation field corresponding to the choosing diameter of the collimation window. It is important to consider the features of electron beam field shaping using a plastic collimator during the electron beam treatment planning.

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