Possibilities of Forming Fields of Uneven Irradiation Using a Multi-Leaf Collimator of Electron Accelerators During Radiation Therapy

Purpose: Consideration the fundamental possibility of forming non uniform irradiation fields (grid diaphragm) using a multi-leaf collimator of an electron accelerator during radiotherapy of cancer patients. Material and methods: The Eclipse planning system was used to model the lattice diaphragm and carry out the corresponding calculations. The tested dosimetric characteristics for open fields of the Clinac iX series accelerators were used as the initial dosimetric data for calculating irradiation plans. Calculation of irradiation plans for the grid diaphragm was carried out in a tissue-equivalent phantom for photon radiation with a nominal energy of 6 MeV. Conclusion: The fundamental and practical possibility of implementing a grating diaphragm formed using a multi-leaf collimator of the electron accelerator of the Clinac iX series (Varian) is shown. A series of dosimetric characteristics of the lattice diaphragm is designed for the Eclipse joint venture. These are depth dose distributions under open and closed areas, dose distribution profiles, dose field lines and dose unevenness coefficients under closed areas between two and four holes. The results obtained can be used as a basis for planning and irradiating patients with a common process with a lattice diaphragm formed using a multileaf collimator.