PURPOSE To propose a method to reduce the slab boundary artifacts in three-dimensional multislab diffusion MRI. METHODS Bloch simulation is used to investigate the effects of multiple factors on slab boundary artifacts, including characterization of residual errors on diffusion quantification. A nonlinear inversion method is proposed to simultaneously estimate the slab profile and the underly...

introduction low dose rate brachytherapy sources have been widely used for interstitial implants in tumor sites, particularly in prostate. dosimetric characteristics of a new irseed 125i brachytherapy source have been determined using the lif thermoluminescent dosimeter (tld) chips. materials and methods dose rate constant, radial dose function, and anisotropy function around the irseed 125i so...

Background: This study aimed to evaluate the dose calculation accuracy of EclipseTM treatment planning system (TPS) in a heterogeneous chest phantom with the intensity modulated radiotherapy (IMRT) technique using EBT3 film and Delta4. Materials and Methods: Two IMRT plans (A and B) were prepared for radiotherapy of the heterogeneous chest phantom. Plan A was between the left lung and the surro...

INTRODUCTION Wide agreement has been reached among the main Bodies and Organizations involved in standardization of radiation protection to define as operational quantity for individual monitoring of external exposure, the personal dose equivalent, Hp(d) (1,2,3). However, as Hp(d) is defined in the human body, it is not a measurable quantity. In practice, it has to be estimated from the indicat...

Background: The advantages of proton beam in radiation therapy- like small lateral scattering as well as absence of exit dose tail in the organs which are after the tumor- make it capable of delivering more treatment doses to the target and much lesser to the critical tissues near it. Materials and Methods: In this study, the Monte Carlo MCNPX code has been used to simulate a slab head phantom ...

BACKGROUND Tumor-Treating Fields (TTFields) are a novel treatment strategy for glioblastoma (GBM) that is approved for the use concomitantly to adjuvant chemotherapy. Preclinical data suggest a synergistic interaction of TTFields and radiotherapy (RT). However, the dosimetric uncertainties caused by the highly dense arrays have led to caution of applying the TTF setup during RT. METHODS In a ...

*Corresponding author: Dr. Asghar Mesbahi, Medical Physics Department, Medical School, Tabriz University of Medical Sciences, Tabriz, Iran. Fax: +98 411 3364660 Email: [email protected] 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 pr...

Introduction Low dose rate brachytherapy sources have been widely used for interstitial implants in tumor sites, particularly in prostate. Dosimetric characteristics of a new IrSeed 125I brachytherapy source have been determined using the LiF thermoluminescent dosimeter (TLD) chips. Materials and Methods Dose rate constant, radial dose function, and anisotropy function around the IrSeed 125I so...

Background: This study was conducted to assess the accuracy of dose calculation near the air-phantom interface of a heterogeneous phantom for Acuros XB (AXB) and Anisotropic Analytical Algorithm (AAA) algorithm of a           6-MV flattening-filter-free beam, compared with film measurements. Materials and Methods: A phantom included air gap was ...