This paper presents an anthropomorphic phantom study of dose delivered to a specific point during tangential breast irradiation to verify monitor unit calculations. Measurements were made using a 0.6 cc Farmer type cylindrical ionization chamber in the phantom and compared to calculations made on a three-dimensional radiotherapy treatment planning system using single digitized contour through t...

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...

A patient dose distribution was calculated by a 3D multi-group S N particle transport code for intracavitary brachytherapy of the cervix uteri and compared to previously published Monte Carlo results. A Cs-137 LDR intracavitary brachytherapy CT data set was chosen from our clinical database. MCNPX version 2.5.c, was used to calculate the dose distribution. A 3D multi-group S N particle transpor...

Deterministic linear Boltzmann transport equation (D-LBTE) solvers have recently been developed, and one of the latest available software codes, Acuros XB, has been implemented in a commercial treatment planning system for radiotherapy photon beam dose calculation. One of the major limitations of most commercially available model-based algorithms for photon dose calculation is the ability to ac...

*Corresponding author: Dr. Mostafa Ghafoori, Radiation Dosimetry and Monitoring group, Agricultural, Medical and Industrial Research School (AMIRS), Nuclear Science and Technology Research Institute (NSTRI), Atomic Energy Organization of Iran (AEOI), P.O. Box 31485-498 Karaj, Iran. Fax: +98 261 4464058 E-mail: [email protected] Background: Absolute dosimetry of external beam radiotherapy is c...

Nowadays, in most radiotherapy departments, the commercial treatment planning systems (TPS) used to calculate dose distributions needs to be verified; therefore, quick, easy-to-use, and low-cost dose distribution algorithms are desirable to test and verify the performance of the TPS. In this paper, we put forth an analytical method to calculate the phantom scatter contribution and depth dose on...

introduction: secondary radiation such as photoelectrons, auger electrons and characteristic radiations cause a local boost in dose for a tumor when irradiated with an external x-ray beam after being loaded with elements capable of activating the tumor, e.g.; i and gd. materials and methods:  in this investigation, the mcnpx code was used for simulation and calculation of dose enhancement facto...

In nuclear medicine and particularly in internal radiotherapy, one of the major challenges is to determine the dose for each patient. Current internal dosimetric estimations are based on the Medical Internal Radiation Dose (MIRD) formalism and use standard mathematical models. These standard models are often far from a given patient morphology and do not allow to perform patient-specific dosime...

introduction: multiple fields and presence of heterogeneities create complex dose distributions that need three dimensional dosimetry. in this work, we investigated mr-based magic gel dosimetry as a three-dimensional dosimetry technique to measure the delivered dose to bladder and rectum in prostate radiation therapy. materials and methods: a heterogeneous slab phantom including bones was made....

background: we aimed to compare field-in-field technique (fif) with conformal tangential field radiotherapy (crt) in terms of dosimetric benefits for early stage breast cancer radiotherapy. materials and methods: twenty consecutive left-side breast cancer patients who underwent breast-conserving surgery were included to the study. for each patient, two different treatment plans were created for...