The aim of the study is evaluation of absorbed doses for thyroids by using neck phantoms. For this purpose, it was arranged the irradiation set with different phantoms. Three different materials were used for phantom materials as, water, paraffin and wood. The phantoms were three different dimensions for simulation of different ages and human race for each material. Co-60 gamma source was used ...

Methods A phantom was built consisting of a single walled chamber with similar axial dimensions to a rat left ventricle. The phantom wall is made from polyvinyl alcohol cryogel (PVAC). The phantom is housed in a sealed polypropylene tube in a water bath. An inlet/outlet hose is used to drive expansion of the phantom, a second outlet allows space for this expansion. The phantom is expanded by a ...

Beam quality correction, kQQ0(r), for solid-state detectors diamond, LiF, Li2B4O7, Al2O3, and plastic scintillator are calculated as a function of distance, r, along the transverse axis of the 60Co and 192Ir brachytherapy sources using the Monte Carlo- based EGSnrc code system. This study also includes calculation of detector-specific phantom scatter correction, kphan(r), for solid phantoms suc...

During pulsed laser lithotripsy, the calculus is subject to a strong recoil momentum which moves the calculus away from laser delivery and prolongs the operation. This study was designed to quantify the recoil momentum during Ho:YAG laser lithotripsy. The correlation among crater shape, debris trajectory, laser-induced bubble and recoil momentum was investigated. Calculus phantoms made from pla...

Division of Medical Physics, University of Leeds, UK Positron range is one important physical limitation to spatial resolution in PET imaging. We present a method to take account of positron range blurring in iterative reconstruction by including specific positron range kernels approximating the annihilation distribution in the forward projection operation [1]. The correction method is implemen...

For determining the absorbed dose of ionizing radiation is tissues, it is essential to have materials which behave like tissues. These kinds of materials are usually called phantom. Up to now many different compounds like water, rubber, Perspex etc have been used. Unfortunately, the practical use of each of them has had its own problems. Our suggested gelatin phantom is very similar to soft...

Background: Recent studies in eye plaque brachytherapy have shown a considerable difference between the dosimetric results using water phantom and a model of human eye containing realistic materials. In spite of this fact, there is a lack of simulation studies based on such a model in proton therapy literatures. In the presented work, the effect of utilizing an eye model with ocular media on pr...

Kilovoltage (kV) cone beam computed tomography (CBCT) images suffer from a substantial scatter contribution. In this study, Monte Carlo (MC) simulations are used to evaluate the scattered radiation present in projection images. These predicted scatter distributions are also used as a scatter correction technique. Images were acquired using a kV CBCT bench top system. The EGSnrc MC code was used...