Studium vlivu intrafrakčního pohybu prostaty na přesnost radioterapie

Abstract

Radiation therapy using CyberKnife system is advanced treatment technique that delivers the optimal therapeutic dose to the target volume with its rapid drop into nearby structures, which results in better local tumour control. Intrafraction correction of motion deviations is provided by robotic arm with a linear accelerator that changes its position after software evaluation of the prostate position from verification images. However, there was a need to analyse the deviations between two individual corrections of the irradiation head position. At this time, there may be some mistakes in the target volume position, in this case prostate, that are larger than the safety radiotherapy margin, and could seriously disrupt the continuity of the delivered dose or cause under-dosing of the target volume. Together with irradiating adjacent healthy tissues, it would reduce the local tumour control and significantly endangered success of the treatment. The theoretical part of this Master Thesis concentrates on the principle of radiotherapy and the biological effects of ionizing radiation on tissues, and the construction of the CyberKnife is also described there. The practical part of the thesis is focused on the statistical analysis of the deviations of the prostate position during its radiotherapy, the design of a suitable safety radiotherapy margin, and realization of the interface used for reading numerical and image data.