Background: Prediction of the absorbed dose in irradiated volume plays an important role in the outcome of radiotherapy. Application of small fields for radiotherapy of thorax makes the dose calculation process inaccurate due to the existence of electronic disequilibrium and intrinsic deficiencies in dose calculation algorithms. To study the lung absorbed dose in radiotherapy with smal...

PURPOSE The purpose of this study is to improve dose calculation accuracy of the simplified Monte Carlo (SMC) algorithm in the low-dose region. Because conventional SMC algorithms calculate particle scattering in consideration of multiple Coulomb scattering (MCS) only, they approximate lateral dose profiles by a single Gaussian function. However, it is well known that the low-dose region spread...

Monte Carlo dose calculations will potentially reduce systematic errors that may be present in currently used dose calculation algorithms. However, Monte Carlo calculations inherently contain random errors, or statistical uncertainty, the level of which decreases inversely with the square root of computation time. Our purpose in this study was to determine the level of uncertainty at which a lu...

BACKGROUND AND PURPOSE To assess the effect of differences in the calculation of the dose outside segment edges on the overall dose distribution and the optimisation process of intensity modulated radiation therapy (IMRT) treatment plans. PATIENTS AND METHODS Accuracy of dose calculations of two treatment planning systems (TPS1 and TPS2) was assessed, to ensure that they are both suitable for...

Current clinical experience in radiation therapy is based upon dose computations that report the absorbed dose to water, even though the patient is not made of water but of many different types of tissue. While Monte Carlo dose calculation algorithms have the potential for higher dose accuracy, they usually transport particles in and compute the absorbed dose to the patient media such as soft t...

Conventional dose calculation algorithms, such as Pencil Beam are proven effective for tumors located in homogeneous regions with similar tissue consistency such as the brain. However, these algorithms tend to overestimate the dose distribution in extracranial regions such as in the lung and head and neck regions where large inhomogeneities exist. Due to the inconsistencies seen in current calc...

The high density and atomic number of hip prostheses for patients undergoing pelvic radiotherapy challenge our ability to accurately calculate dose. A new clinical dose calculation algorithm, Monte Carlo, will allow accurate calculation of the radiation transport both within and beyond hip prostheses. The aim of this research was to investigate, for both phantom and patient geometries, the capa...