Acceptance modulated radiation intensity and enhanced dynamic wedge using 2D ion chamber array

Abstract

Dynamic techniques for dose delivering used in external radiotherapy such as modulated radiation intensity (IMRT) and enhanced dynamic wedges (EDW) tend to be used with more frequency due to the benefits in terms of higher treatment dose to the tumor while preserving the exposure of healthy tissues and reduction in treatment times needed in wedged beam techniques, respectively. In seeking to ensure accuracy in dose delivery in dynamic techniques are several the measurement methods and systems developed. One of the factors of interest to medical physicists who daily use these techniques in the clinic routine is the quick and easy configuration of measurement systems and analysis to carry out QA tests. This paper presents the results of tests of acceptance for Intensity Modulated Radiation Therapy and Enhanced Dynamic Wedge Commissioning made on a Varian iX with 6 and 10 MV energies using a 2D array ionization chamber Octavius2D. This paper presents the results of acceptance tests for IMRT and EDW commissioning made on a 6 and 10 MV Varian iX using a 2D array Octavius2D PTW ionization chamber. Acceptance factors considered were: absolute dose delivery, reproducibility and exactitude fluence patterns, dose profile and QA of specific patient. The results obtained show a good accordance with the field parameters having higher acceptance percentages to 90% in all realized tests.