Design optimization of intraoperative radiotherapy cones.

Purpose: Electron intraoperative cones (EIORCs) commonly used for intraoperative radiation therapy (IORT) often generate high-dose regions at superficial depths. This study was performed to optimize the use of rings in the EIORC design that reduces the high-dose region while minimizing the loss of the treatment volume at the prescribed depth.

Methods And Materials: Monte Carlo simulations were performed to study the dosimetry properties of various EIORC designs.

Applications of simulator computed tomography number for photon dose calculations during radiotherapy treatment planning.

Purpose: To study the variation of computed tomography (CT) number from a simulator-based scanner and the effect of this variation on photon-dose calculations.

Method And Materials: CT images of a cylindrical phantom with multiple inserts were obtained using a commercially-available simulator-CT (Ximatron: Varian, Palo Alto, CA). The linear correlation coefficient and Chi-square methods were used to determine the X-ray effective energy in a phantom.