رضاپور, جعفر

دانشگاه علوم پزشکی شهید بهشتی

[ 1 ] - مقایسه میزان دز جذبی پستان در دستگاه ماموگرافی معمولی و دیجیتال در شرایط مورد استفاده دستگاه‌ها در تبریز

Background: The amount of doses received in mammography is one of the biggest concerns in the world. According to some statistics, every 12 minutes a woman dies due to breast cancer. Mammography concerned to detect breast cancer at an early stage of the disease as well as for screening, however due to the risk of exposure, the increasingly and widespread use of mammography for breast cancer scr...

[ 2 ] - Camera based EPID dosimetric verification of radiation treatments

Introduction: Tumor control and treatment quality depend on accuracy of delivered dose. Various methods have been studied for treatment dosimetry verification. Among these methods, the use of electronic portal imaging device (EPID) is highly considered. Many efforts are underway to improve the results of this context.   Materials and Methods: In this study, ...

[ 3 ] - Small field size dose-profile measurements using MAGIC- f polymer gel dosimeter and EBT3 film dosimeter

Introduction: In radiotherapy, treatment planning methods are evaluating and transforming every day, so precision in calculation and determination of dose delivery process is performing more important role in radiotherapy than past. In modern radiotherapy treatments, deramatically increase of small fields utilization, causes the polymeric gels has known as the most reliable dos...

[ 4 ] - Calculation of air gaps between bolus and skin on the dose received from the skin

    Introduction: In the last few decades, a lot of monte carlo codes have been introduced for medical applications. For close - to - surface tumors, the surface of the skin can be used to increase the surface dose so that all or part of the bunch area can fall into bolus, thereby increasing the dose of the skin. The air gaps between bolus and skin can affect the dose of...

[ 5 ] - Calculation the phantom scatter factor for the linear accelerators device

Introduction: In the last few decades, a lot of monte carlo codes have been introduced for medical applications. this is important because through simulation, we are fully independent of the spectral scattering factor that we are not able measure in real terms. The effect of the radiation energy, the dimension of the radiation field, the sensitive volume of the ion chamber on t...

[ 6 ] - Investigation of dosimetric characteristic of NIPAM polymer gel using x-ray CT

Introduction: Polymer gel dosimeters contain chemical materials sensitive to the radiation which are polymerized by the radiation as a function of absorbed dose. So information of spatial dose distribution can be extracted by imaging from irradiated gel. Among imaging techniques, computed tomography (CT) poses as an attractive method because of practical advantages such as acce...

[ 7 ] - Investigation of Freedom-Degrees impact on Modulation of Radiation

Introduction: Nowadays tendency to apply more degrees of freedom in high-tech radiotherapy systems, and consequent complex process to optimize dose calculation and delivery algorithms, is a challenge of radiation therapy optimization. Faster MLC speed, dose rate, Gantry angle variation, and other degrees, which have been utilized in IMRT, IMAT, VMAT, improved modulation of inte...

[ 8 ] - Designing Optimal Bias Voltage for Radiotherapy Diamond Dosimeter

Introduction: Recent developments of radiotherapy techniques, require high accuracy detectors to determine the delivered dose in a small area. Chemical vapor deposition (CVD) or naturally growth diamond detectors which are commercially available are good candidates for this purpose. In these detectors two electrodes with high different electrical potential are deposited on both...

[ 9 ] - Breast dose in conventional and digital mamography

Introduction: The amount of doses received in mammography is one of the biggest concerns in the world. According to some statistics, every 12 minutes a woman dies due to breast cancer. Mammography concerned to detect breast cancer at an early stage of the disease as well as for screening, however due to the risk of exposure, the increasingly and widespread use of mammography fo...

[ 10 ] - Pseudo-CT Generation from Magnetic Resonance Imaging by fuzzy look up table algorithm

Introduction: Despite growing interest in the use of magnetic resonance imaging (MRI) in the external radiotherapy design process (RT), Computer Tomography (CT) remains a gold standard and is regarded as a basic imaging modality in radiotherapy. MRI shows the high contrast in soft tissues without any radiation exposure to patients. As a result, MRI is used in functional tissue ...

[ 11 ] - Beam characteristic of P.E collimators Add-on multileaf collimator

  Introduction:    Multileaf collimators (MLCs) are computer-controlled devices which are Useful and cost-effective tools for conformal therapy and intensity modulation radiotherapy (IMRT). Nowadays MLCs are important and standard configuration of the new medical linear accelerators which are substitute of conventional Blocks and has eliminated the ...

[ 12 ] - Comparison dose distributions from gamma knife unit 4C with CT data and non-CT data options of beamnrc code

Todays gamma knife radiosurgery is used widely for treatment of very small brain tumors. In order to investigate accuracy of dosimetry and treatment planning calculations, using Monte Carlo simulation with dedicated code named as beamnrc including non-CT data and CT data options is necessary. The aim of this study is choosing the best options in order to have an accurate tools based on their ad...