RADIOTHERAPY SYSTEM PROVIDED WITH A PROGRAM FOR CALCULATION OF THE INTENSITY OF AN ELECTRON BEAM Russian patent published in 2018 - IPC A61N5/10 

FIELD: medical equipment.

SUBSTANCE: invention relates to medical equipment, in particular to systems for radiotherapy. System comprises: free electron accelerator, equipped with an applicator, image capture device, a built-in control unit, display for forming two-dimensional or three-dimensional images and a computer, and an active radiation dose sensor that can be installed between the distal end of the applicator and said zone (Z). Computer is equipped with a program for calculating the intensity of an electron beam, which contains the following steps: (i) setting a first intensity of the electron beam according to operation and geometric characteristic parameters of the electron accelerator and / or calculated by Monte Carlo method, and also according to at least one predefined image of the zone (Z), intensity is emitted by means of the electron accelerator during a first radiation; (ii) operating the electron accelerator for emitting the first electron beam in the first radiation corresponding to a fraction of the first intensity set in the step (i); (iii) detecting a real intensity of the first electron beam during the first radiation by means of the radiation sensor, placed in accordance with the zone (Z); (iv) capturing at least one area image by the image capture device; (v) calculating an intermediate intensity of the electron beam according to at least one image captured the step (iv), and according to the real intensity of the first electron beam detected in the step (iii); (vi) comparing the first intensity set in the step (i), with the intermediate intensity calculated in the step (v), to calculate the final intensity of the electron beam, by which the zone (Z) can be irradiated during the second radiation after the first radiation. Calculation of the final intensity in the step (vi) is performed according to the following equation:

,

where is the matrix that represents the final intensity calculated in the step (vi), that can be emitted during the second radiation, index k represents the depth of the medium through which the electron beam passes, g (i, j, l) is the original matrix of the data related to the first intensity set in the step (i), ρ_l - electron density with regard to water, Δ_z - the voxel dimension of at least one image captured in the step (iv), along the axis of the electron beam, i and j represent the starting point of the path of radiation in the zone (Z).

EFFECT: invention makes it possible to screen completely or exclude temporarily a healthy tissue from the treated area.

5 cl, 11 dwg