The aim of this report is to present a new two-piece thyroid-neck phantom produced by the concurrent use of epoxy resin and poly(methyl methacrylate) (PMMA: plexiglass) soft tissue equivalent materials. Accordingly, mass attenuation coefficients of the epoxy resin and the plexiglass compounds were obtained from simulation (NIST XCOM 3.1) and measurements (practical dosimetry) and compared to th...

OBJECTIVE The aim of this study is to evaluate the effect of tissue composition on dose distribution in electron beam radiotherapy. METHODS A Siemens Primus linear accelerator and a phantom were simulated using MCNPX Monte Carlo code. In a homogeneous cylindrical phantom, six types of soft tissue and three types of tissue-equivalent materials were investigated. The tissues included muscle (sk...

introduction the gamma knife system is designed solely for non-invasive treatment of brain disorders, and it benefits from stereotactic surgical techniques. dose calculations required in the system are performed by gammaplan code; in this code, brain tissue is considered uniform. in the present study, we evaluated the effect of gamma knife system on the obtained dose through simulating a real h...

An evaluation of two anthropomorphic breast phantoms, which have been designed for quality assurance and dose verification of radiotherapy treatment of breast cancer patients, is presented. These phantoms are identical in terms of their dimensions and shape, and composed of several layers of either Plastic Water or tissue-equivalent material. Both water- and tissue-equivalent phantoms include l...

A breast tissue-equivalent series (BRTES) of phantoms is manufactured to mimic both the attenuation and the density of the range of glandular and adipose tissue compositions encountered in mammography. The BRTES simulates breast tissues across the range of 20% to 70% glandularity and can be assembled in a variety of thicknesses to represent a compressed breast thickness corresponding to glandul...