Verification of collapsed cone convolution algorithm for dose calculation by computer - based system in treatment planning
Keywords:computerized treatment planning system, collapsed cone convolution algorithm, homogeneity phantom, heterogeneity phantom
In radiation therapy, computerized-based treatment planning system is used to calculate dose distribution in order to consider the radiation dose at tumors and normal organs. The accuracy of dose calculation algorithm is very important for treatment planning systems (TPS). The purpose of this study was to verify the accuracy of dose calculation in collapsed cone convolution algorithm. To verify the accuracy of TPS, dose measurement was compared with TPS. Verification was performed in two conditions as follows: homogeneity and heterogeneity media. For homogeneity media, the dose difference between calculations and measurments in all radiation energys (6MV, 10MV, 15MV, 6MV-FFF, 10MV-FFF) were < 2% for simple radiation filed and < 3% for Multileaf collimator shaped fields. For heterogeneity media, the dose difference between calculations and measurments in all radiation energys were < 3% for inner radiation beam and < 4% for penumbra regoin. This indicated that collapsed cone convolution algorithm has enougth accuracy to perform dose calculation in homogeneity and heterogeneity media.