Development of a diode dosimetric system for quality control of radiotherapy units

A diode dosimetric system was developed and tested for quality control of photon and electron beams as used in radiotherapy. The following tests were done: repeatability and reproducibility, linearity, degradation with dose and response with the field size. These results were compared with the response of ionization chambers. For the most tests, the diode system presented similar response of it, which demonstrated its viability for clinical dosimetry use. A quality assurance program for a multi-beam accelerator was proposed as an example of its application in a routine use for a radiotherapy service. Besides its practicability of using, the system presents the advantage of low cost, compared to imported system in use nowadays. (author)