RESUMO
A method of correcting the output dose rate of the radiotherapeutic cobald units is presented. This method links measurements values with the decay formula for increasing the accuracy of output dose rate determining. The least squares method has been applied to mathematical processing of the data. Results were discussed on the record of output dose rate which had been measured since 1969.
Assuntos
Radioisótopos de Cobalto/uso terapêutico , Neoplasias/radioterapia , Radioterapia/métodos , Humanos , Radioterapia/instrumentaçãoRESUMO
A quick method of calculating the dose-rate distribution in irregularly shaped beams is presented. This method is partly based on the Cunningham model. The proposed modifications make it possible to avoid the scatter functions in favor of direct use of tissue-phantom ratios and field size coefficients. The problem has been evaluated for photons generated by 10 and 23 MV linacs. The calculated dose rates have been compared with measured ones, and good accuracy has been achieved.
