Patient-specific verification of intensity-modulated radiation therapy (IMRT) plans can be done by dosimetric measurements or by independent dose or monitor unit calculations. The aim of this study was the clinical evaluation of IMRT verification based on a fast Monte Carlo (MC) program with regard to possible benefits compared to commonly used film dosimetry. 25 head-and-neck IMRT plans were r...

Relative absorbed dose energy response correction, R, for various radiochromic films in water phantom is calculated by the use of the Monte Carlo-based EGSnrc code system for high energy brachytherapy sources 60Co, 137Cs, 192Ir and 169Yb. The corrections are calculated along the transverse axis of the sources (1-15 cm). The radiochromic films investigated are EBT, EBT2 (lot 020609 and lot 03110...

background: gel polymers are considered as new dosimeters for determining radiotherapy dose distribution in three dimensions. objective: the ability of a new formulation of magic-f polymer gel was assessed by experimental measurement and monte carlo (mc) method for studying the effect of gold nanoparticles (gnps) in prostate dose distributions under the internal ir-192 and external 18mv radioth...

*Corresponding author: Dr. Tayyeb Allahverdi Pourfallah, Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran, Iran. Fax: +98 21 88973653 E-mail: [email protected] Background: Polymer gel dosimetry is still the only dosimetry method for direct measuring of threedimensional dose distributions. MRI Polymer gel dosimeters are tissue equi...

Background: The presence of a wedge filter in the beam trajectory can modify the beam quality and cause some changes in the dosimetry parameters which are usually difficult to be measured directly and accurately. Material and Methods: In this study the MCNP-4C Monte Carlo code was used to simulate the 9 MV photon beam generated by a linear accelerator. Upon getting a good agreement bet...

Thoracic cancer treatment presents dosimetric difficulties due to respiratory motion and lung inhomogeneity. Monte Carlo and deformable image registration techniques have been proposed to be used in four-dimensional (4D) dose calculations to overcome the difficulties. This study validates the 4D Monte Carlo dosimetry with measurement, compares 4D dosimetry of different tumor sizes and tumor mot...

PURPOSE The aim of this study was to combine a set of methods for use of radiochromic film dosimetry, including calibration, correction for lateral effects and a proposed triple-channel analysis. These methods can be applied to GAFCHROMIC EBT3 film dosimetry for radiation field analysis and verification of IMRT plans. METHODS A single-film exposure was used to achieve dose calibration, and th...

Introduction: Monte Carlo calculation method is considered to be the most accurate method for dose calculation in radiotherapy. The purpose of this research is comparison between 6 MV Primus LINAC simulation output with commissioning data using EGSnrc and build a Monte Carlo geometry of 6 MV Primus LINAC as realistically as possible. The BEAMnrc and DOSXYZnrc (EGSnrc package) M...

www.onk.ns.ac.rs/Archive Vol 20, No. 1–2, July 2012 INTRODUCTION The GZP6 high dose rate (HDR) afterloading brachytherapy unit (Nuclear Power Institute of China) (1) has recently been introduced in the Iranian radiation oncology centers. The unit has six different cobalt-60 source braids being loaded in tandem and ovoid applicators. The sources are used in the treatment of cervix, vagina, rectu...

Curative breast radiotherapy typically leaves patients with varying degrees of cosmetic damage. One problem interfering with cosmetically acceptable breast radiotherapy is the external contour for large pendulous breasts which often results in high doses to skin folds. Thermoplastic casts are often employed to secure the breasts to maintain setup reproducibility and limit the presence of skin f...