Caracterización experimental de núcleos de convolución en radioterapia con modulación de intensidad

Resumo

The objective of radiation therapy is the treatment of tumors with radiations. In order to achieve an efficient radiotherapy process, the development of algorithms that lead to accurate dose calculations is very important. In this work a new procedure for beam characterization and a dose calculation algorithm valid in intensity modulated radiation therapy (IMRT) conditions have been developed. The beam characterization is based on deconvolution with the Hankel transform. The comparisons between calculations and measurements demonstrate that it is a valid procedure for dose calculations in IMRT. The dosimetric problems that arise in these beams have been discussed and managed properly. The comparisons between our calculations, those from a commercial software, and measurements agreed well. Finally, the gel dosimetry is introduced. Applied to our research, it could lead to the characterization of a three dimensional kernel with only one measurement. The difficulties that make this technique being still a mattre of research are discussed. Extensions of this development are the application to charged particles and to the dose calculation based on measurements taken with a flat panel.