Mehdi Zehtabian

School of Mechanical Engineering, Shiraz University, Shiraz, Iran

[ 1 ] - Evaluation of the Entrance Skin Dose in Animals Undergoing Diagnostic Radiology Using LiF, Mg, Ti Thermoluminescence Dosimetry (TLD-100)

Introduction According to the International Commission on Radiological Protection publication numbers 60 and 21, the environmental control standards should ensure human and other species protection to a desirable degree. Since application of radiographic procedures in Veterinary Medicine has increased significantly, in this study, we aimed to evaluate the entrance skin dose to the animals (e.g....

[ 2 ] - Design of Light Multi-layered Shields for Use in Diagnostic Radiology and Nuclear Medicine via MCNP5 Monte Carlo Code

Introduction Lead-based shields are the most widely used attenuators in X-ray and gamma ray fields. The heavy weight, toxicity and corrosion of lead have led researchers towards the development of non-lead shields. Materials and Methods The purpose of this study was to design multi-layered shields for protection against X-rays and gamma rays in diagnostic radiology and nuclear medicine. In this...

[ 3 ] - Material-specific Conversion Factors for Different Solid Phantoms Used in the Dosimetry of Different Brachytherapy Sources

Introduction Based on Task Group No. 43 (TG-43U1) recommendations, water phantom is proposed as a reference phantom for the dosimetry of brachytherapy sources. The experimental determination of TG-43 parameters is usually performed in water-equivalent solid phantoms. The purpose of this study was to determine the conversion factors for equalizing solid phantoms to water. Materials and Methods T...

[ 4 ] - Investigation of Anisotropy Caused by Cylinder Applicator on Dose Distribution around Cs-137 Brachytherapy Source using MCNP4C Code

Introduction: Brachytherapy is a type of radiotherapy in which radioactive sources are used in proximity of tumors normally for treatment of malignancies in the head, prostate and cervix. Materials and Methods: The Cs-137 Selectron source is a low-dose-rate (LDR) brachytherapy source used in a remote afterloading system for treatment of different cancers. This system uses active and inactive sp...

[ 5 ] - Investigation of the Effects of Tissue Inhomogeneities on the Dosimetric Parameters of a Cs-137 Brachytherapy Source using the MCNP4C Code

Introduction: Brachytherapy is the use of small encapsulated radioactive sources in close vicinity of tumors. Various methods are used to obtain the dose distribution around brachytherapy sources. TG-43 is a dosimetry protocol proposed by the AAPM for determining dose distributions around brachytherapy sources. The goal of this study is to update this protocol for presence of bone and air inhom...

[ 6 ] - کاوشی در عوامل اثر‌گذار بر کیفیت استفاده از فناوری ویدئو کنفرانس در آموزش‌های مهندسی

پژوهشهای اخیر نشان داده‌اند که فنّاوری ویدئو‌کنفرانس،‌ هم‌اکنون به‌ عنوان راهبردی سودمند برای ارتباط استاد با دانشجو در محیطهای یاددهی و یادگیری در دانشگاهها و مراکز آموزش عالی کاربرد دارد. هدف مقالة کنونی، کاوشی پیرامون عوامل اثر‌گذار بر ارتقای کیفیت بهره‌گیری از فناوری ویدئو‌کنفرانس در آموزشهای مهندسی است. روش پژوهش مورد‌ استفاده در این پژوهش، مطالعة موردی بوده است. به‌منظور تحقق هدف پژوهش، با...

[ 7 ] - Comparison of dosimetry parameters of two commercially available Iodine brachytherapy seeds using Monte Carlo calculations

Background: Iodine brachytherapy sources with low photon energies have been widely used in treating cancerous tumors. Dosimetric parameters of brachytherapy sources should be determined according to AAPM TG-43U1 recommendations before clinical use. Monte Carlo codes are reliable tools in calculation of these parameters for brachytherapy sources. Materials and Methods: Dosimetric param...

[ 8 ] - Designed free-lead composite shields for diagnostic medicine radiation fields by using MCNPX code

 Introduction: Nowadays, applications of free-lead radiation shields are increased specially for weighting factor and toxicity of lead elements. Although touching the lead may be results in the nervousand blood system of body, it is not exactly proven yet. Protective measures are the fundamental parts of radiation protection. On the other hand, high weighting factor of lead sh...