Purpose This study is intended to compare dose-volume parameters evaluated using different forward planning- optimization techniques, involving two applicator systems in intracavitary brachytherapy for cervical cancer. It looks for the best applicator-optimization combination to fulfill recommended dose-volume objectives in different high-dose-rate (HDR) fractionation schedules. Material and ...

Introduction: Nowadays tendency to apply more degrees of freedom in high-tech radiotherapy systems, and consequent complex process to optimize dose calculation and delivery algorithms, is a challenge of radiation therapy optimization. Faster MLC speed, dose rate, Gantry angle variation, and other degrees, which have been utilized in IMRT, IMAT, VMAT, improved modulation of inte...

Monte Carlo (MC) is rarely used for IMRT plan optimization outside of research centres due to the extensive computational resources or long computation times required to complete the process. Time can be reduced by degrading the statistical precision of the MC dose calculation used within the optimization loop. However, this eventually introduces optimization convergence errors (OCEs). This stu...

A methodology for the concurrent optimization of beam orientations and beam weights in conformal radiotherapy treatment planning has been developed and tested on a cohort of five patients. The algorithm is based on a beam-weight optimization scheme with a downhill simplex optimization engine. The use of random voxels in the dose calculation provides much of the required speed up in the optimiza...

The annual number of computed tomography (CT) procedures in the U.S. has increased 20-fold (from 3 to 60 million) between 1985 and 2005 (1), and as a result, the average (i.e., per capita) annual background dose in the U.S. has nearly doubled from 3.0 to 5.6 mSv (2). This has precipitated increasing societal concern over the potential public health impact—an increased risk of cancer—associated ...