AIM This work investigated the dosimetric properties of a 10-MV photon beam emitted from a medical linear accelerator (linac) with no flattening filter (FF). The aim of this study is to analyze the radiation fluence and energy emitted from the flattening filter free (FFF) linac using Monte Carlo (MC) simulations. MATERIALS AND METHODS The FFF linac was created by removing the FF from a linac ...

A software program, SpekCalc, is presented for the calculation of x-ray spectra from tungsten anode x-ray tubes. SpekCalc was designed primarily for use in a medical physics context, for both research and education purposes, but may also be of interest to those working with x-ray tubes in industry. Noteworthy is the particularly wide range of tube potentials (40-300 kVp) and anode angles (recom...

Technical developments in radiotherapy (RT) have created a need for systematic quality assurance (QA) to ensure that clinical institutions deliver prescribed radiation doses consistent with the requirements of clinical protocols. For QA, an ideal dose verification system should be independent of the treatment-planning system (TPS). This paper describes the development and reproducibility evalua...

PURPOSE Lipiodol, which was used in transcatheter arterial chemoembolization before liver stereotactic body radiation therapy (SBRT), remains in SBRT. Previous we reported the dose enhancement in Lipiodol using 10 MV (10×) FFF beam. In this study, we compared the dose enhancement in Lipiodol and evaluated the probability of electron generation (PEG) for the dose enhancement using flattening fil...

background: accurate small radiation field dosimetry is essential in modern radiotherapy techniques such as stereotactic radiosurgery (srs) and intensity modulated radiotherapy (imrt). precise measurement of dosimetric parameters such as beam profile, percentage depth doses and output factor of these beams are complicated due to the electron disequilibrium and the steep dose gradients. in the p...

PURPOSE To design an efficient method for utilizing phase-space source models in the GPU-based Monte Carlo (MC) dose calculation engine gDPM. METHODS In GPU-based MC algorithms, particles are transported in parallel on different threads. Particles of different types and energies can require significantly different execution times. This can cause "thread divergence" and lower efficiency when s...

Nghiên cứu này áp dụng phương pháp mô phỏng Monte Carlo Mã EGSnrc với hai mã là chuyên dụng, BEAMnrc được sử để chùm tia phát ra từ đầu máy gia tốc và DOSXYZnrc tính toán liều lượng tốc. Từ đó, đánh giá sự suy giảm của bức xạ qua các lớp vật liệu che chắn. Kết quả nghiên ban cho thấy giới hạn ở khu vực nhân viên (khu Kiểm soát) 0,11 mSv / tuần (5,5 năm) công cộng Không kiểm 0,022 (1,1 ).

Background: Physical wedges are still widely used as beam modifiers in external beam radiotherapy. However the presence of them in the beam trace may cause beam hardening which may not be considered in many treatment planning systems. The aim of this study is to investigate the beam hardening effect generated by physical wedges via different beam quality indexes as photon spectrum, half value l...

Background:  This study presents patient specific and organ dose estimation in computed tomography (CT) imaging of thorax directly from patient CT image using Monte Carlo simulation.  Patient's CT image is considered as the patient specific phantom and the best representative of patient physical index in order to calculate specific organ dose. Materials and Methods: EGSnrc /BEAMnr...