PURPOSE The goal of this study is to determine whether the magnitude of overlap between planning target volume (PTV) and rectum (Rectumoverlap) or PTV and bladder (Bladderoverlap) in prostate cancer volumetric-modulated arc therapy (VMAT) is predictive of the dose-volume relationships achieved after optimization, and to identify predictive equations and cutoff values using these overlap volumes...

Introduction: In brachytherapy treatments, high-dose sources are used in interstitial placement. In this paper, the modeling of a common breast cancer treatment applicator called MammoSite is done by the Monte Carlo simulation code. Then, to study and calculate the amount of doses in the breast and the dose rate of the organs at risk of radiation, including: lungs, ribs and ski...

BACKGROUND To protect neurological tissues, underdosing occurs in most cases of T4 nasopharyngeal carcinoma (NPC) with intracranial extension. In this study, we aimed to evaluate the effect of dosimetric inadequacy on local control and late neurological toxicities for patients treated with intensity-modulated radiotherapy (IMRT) plus chemotherapy. METHODS We prospectively enrolled patients wh...

Positional, tangential, and orthogonality constraints are all linear and can be easily incorporated into freeform curve and surface editing and manipulation environment. In this paper, we show that the area and volume constraints that are traditionally considered non linear and hence diicult to handle, can indeed be reformulated as linear constraints and similarly incorporated with ease into ed...

PURPOSE Limits on mean lung dose (MLD) allow for individualization of radiation doses at safe levels for patients with lung tumors. However, MLD does not account for individual differences in the extent or spatial distribution of pulmonary dysfunction among patients, which leads to toxicity variability at the same MLD. We investigated dose rearrangement to minimize the radiation dose to the fun...

INTRODUCTION The aim of this study was to compare various coplanar and non-coplanar 3-dimensional conformal radiation therapy (3DCRT) beam arrangements for the delivery of stereotactic ablative radiation therapy (SABR) to patients with early stage lung cancer, based on the dosimetric criteria from the Radiation Therapy Oncology Group (RTOG) 1021 protocol. METHODS Ten medically inoperable lung...

The purpose of this work is to investigate if the change in plan quality with the finer leaf resolution and lower leakage of the 160 MLC would be dosimetrically significant for head and neck intensity-modulated radiation therapy (IMRT) treat- ment plans. The 160 MLC consisting of 80 leaves of 0.5 cm on each bank, a leaf span of 20 cm, and leakage of less than 0.37% without additional backup jaw...