Comparison of the deviation distribution in the doses administrated with and without mask in radiotherapeutic procedures

In order to guarantee that the error limit in the dose administration is inside of the recommended limit by the ICRU (the ICRU recommends that the doses administrated in radiotherapy must be inside of a total deviation ± 5 %), the radiotherapy services are maintaining quality control programs and dosimetry which guarantee that the equipment yield or source should be known with precision. The Quality Control Programs foresee moreover the radiation beam calibration dosimetry, the In vivo dosimetry for obtaining a greater control of the administered doses. At present it counts on greater devices for maintaining the deviations inside this margin, and one of them is the u se of masks. The present work was carried out on a Siemens equipment model Gammatron S-80 (Co-60) in the Radiotherapy Service of the Sao Paulo University Hospital where teletherapy procedures are realized. (Author)