Background: In radiotherapy, the accuracy of dose calculation systems plays a key role in the treatment of cancer patients.
Objective: The current research aimed to evaluate the dose calculation accuracy of Monaco Treatment Planning System (TPS) in estimating the Effective Wedge Angle (EWA) using two different mathematical methods: Elekta formula and ICRU-24 formula.
Material And Methods: In this experimental study, EWAs for different field sizes (5×5, 10×10, 15×15, 20×20, 25×25, and 30×30 cm) at standard angles (15°, 30°, 45°, and 60°) were computed by the Monaco TPS using two different analytical methods.
This review examines the literature on the assessment of photon beam skyshine dose rates in medical accelerator radiotherapy with an energy range of 4-25 MV. The selected studies focus on medical accelerators within radiotherapy facilities and employ various methodologies for calculating photon beam skyshine dose rates. Researchers utilized Monte Carlo (MC) simulations, direct measurements, and empirical methods outlined in NCRP Reports 151 and 51 for skyshine estimations.
View Article and Find Full Text PDFThis study aimed to estimate the effective dose and the risk of exposure-induced cancer death (REID), as well as to establish diagnostic reference levels (DRLs) for common CT examinations conducted in Tabriz, Iran. The investigation included adult patients undergoing abdomen-pelvis, brain, neck, sinus, and chest CT scans. Patient data, exposure parameters, and radiation dose metrics, such as volume CT dose index (CTDI) and dose length product (DLP), were collected and analyzed.
View Article and Find Full Text PDFTumors can produce bioactive substances called tumor-derived supernatants (TDS) that modify the immune response in the host body. This can result in immunosuppressive effects that promote the growth and spread of cancer. During tumorigenesis, the exudation of these substances can disrupt the function of immune sentinels in the host and reinforce the support for cancer cell growth.
View Article and Find Full Text PDFBackground: Breast cancer requires evaluating treatment plans using dosimetric and biological parameters. Considering radiation dose distribution and tissue response, healthcare professionals can optimize treatment plans for better outcomes.
Objective: This study aimed to evaluate the effects of the different Dose Calculation Algorithms (DCAs) and Biologically Model-Related Parameters (BMRPs) on the prediction of cardiopulmonary complications due to left breast radiotherapy.
This study aimed to estimate lung and breast doses for individual patients using the size-specific dose estimate (SSDE) method, as well as calculating effective doses, in patients who underwent chest CT scans during the COVID-19 pandemic. Cancer risk incidence was estimated using excess relative risk (ERR), excess absolute risk (EAR), and lifetime attributable risk (LAR) models from the Biological Effects of Ionizing Radiation Report VII (BEIR-VII). Data from about 570 patients who underwent CT scans for COVID-19 screening were utilized for this study.
View Article and Find Full Text PDFBackground: Functional dyspepsia (FD) is felt as a discomfort or pain on the center line or upper abdomen. In this study, we aimed to compare the effects of Govarcin herbal capsule and Metoclopramide for alleviating gastrointestinal symptoms in patients with FD.
Methods: Totally, 106 patients enrolled in a double-blind, clinical trial study.
Background: Virtual wedge (VW) is used in radiotherapy to compensate for missing tissues and create a uniform dose distribution in tissues. According to TECDOC-1583 and technical reports series no. 430, evaluating the dose calculation accuracy is essential for the quality assurance of treatment planning systems (TPSs).
View Article and Find Full Text PDFBackground And Objective: Herniarin is a simple coumarin that is found naturally in some plant species. In this study, we aimed to evaluate the protective effect of herniarin against ionizing radiation-induced genotoxicity and cytotoxicity in human peripheral blood lymphocytes.
Methods: Herniarin was added to human lymphocytes before irradiation with a dose of 2 Gy of Xrays.
Background And Objectives: Anti-tumor activity of some thioureas derivatives is well documented in literature and received considerable attention. The present study aims to synthesize and characterize some novel thioureas and carbonylthioureas as anti-tumor agents for MCF-7 breast cancer cells in vitro and in vivo.
Materials And Methods: Several 1-allyl-3-(substituted phenyl), N,N'-(phenylene) bis(3- allyldithithiourea) and 1-cyclopropanecarbonyl-3-(substituted phenyl)-thioureas derivatives were synthesized and confirmed by FT-IR spectroscopy, NMR and C-NMR.
This study evaluated the basic dosimetric characteristics of a Dynamic Multi Leaf Collimator (DMLC) using a diode detector and film measurements for Intensity Modulated Radiation Therapy Quality Assurance (IMRT QA). The EGSnrc Monte Carlo (MC) simulation system was used for the determination of MLC characteristics. Radiation transmission and abutting leaf leakage relevant to the LinaTech DMLC H were measured using an EDGE detector and EBT3 film.
View Article and Find Full Text PDFIn radiation cancer treatments, the most of the side effects could be minimized using a proper dosimeter. Gel dosimeter is the only three-dimensional dosimeter and magnetic resonance imaging (MRI) is the gold standard method for gel dosimeter readout. Because of hard accessibility and high cost of sample reading by MRI systems, some other alternative methods were developed.
View Article and Find Full Text PDFBackground: The impact of intravenous (IV) contrast media (CM) on radiation dose calculations must be taken into account in treatment planning.
Purpose: The aim of this study is to evaluate the effect of an intravenous contrast media on dose calculations in three-dimensional conformal radiation therapy (3D-CRT) for lower esophageal and rectal cancers.
Materials And Methods: Seventeen patients with lower esophageal tumors and 12 patients with rectal cancers were analyzed.