Introduction: Small field dosimetry is challenging for radiotherapy dosimetry. measurement of the output factor in the air and water (Sc, Scp) is one of the input parameters for commissioning of treatment planning systems and beam modeling. The aims of this study are to measured Sc,Scp for small fields with EBT2 and Ion chamber and design a appropriate mini-phantom for small fi...

Introduction: Exposure to ionizing radiation can be through direct hit or water radiolysis lead to oxidation in biological systems. In this study, the protective effect of Myrtus Communis aqueous extract on structural changes and oxidative stress in red blood cells and plasma proteins was examined after receipt of ionizing radiation. Materials and Methods: wis...

Background: The Shielding methods in radiotherapy due to delivering an accurate radiation dose to cancer tissues and avoiding unnecessary dose to normal tissues are very important. These methods include Lead standard blocks, individual molding and multi leaf collimator (MLC). The MLC method is not still common in Iran radiotherapy centers. Individual molding is better than the lead block shield...

Background: 7-LiF: Mg,Cu,P (GR-207A) is one kind of thermo-luminescent dosimeters (TLD) which can be used in diagnostic radiology and radiotherapy applications. Because of having suitable properties such as good sensitivity, small size and being tissue equivalent, thermo-luminescent dosimetry has been one of the most important techniques in medicine over many years. Choosing a correct energy fo...

Background: New treatment modalities are developed with the aim of escalating tumor absorbed dose and simultaneously sparing the normal structures. The use of nanotechnology in cancer treatment offers some possibilities including destroying cancer tumors with minimal damage to healthy tissues. Zinc Oxide nanoparticles (ZnO NPs) are wide band gap semiconductors and seem to have a good effect on ...

Background: The accuracy and the reproducibility of radiotherapy can be provided by using immobilization devices such as thermoplastic masks. In head and neck cancer radiotherapy, the patients are mostly immobilized by using thermoplastic masks. In this study, the effect of the thermoplastic mask to the surface and buildup region doses was investigated by using Markus parallel plate ion chamber...

Some aspects of the electronic and active membrane properties of nonspiking local interneurons were studied in isolated locust thoracic ganglia, using the switched current- and voltage-clamp techniques in neuropilar recordings. The average transmembrane potential (Vr) of the interneurons was -58 +/- 6mV (n = 85), and the input resistance (in the linear region of the current-voltage curve) was 1...

As flattening filter-free (FFF) photon beams become readily available for treat-ment delivery in techniques such as SBRT, thorough investigation of skin dose from FFF photon beams is necessary under clinically relevant conditions. Using a parallel-plate PTW Markus chamber placed in a custom water-equivalent phantom, surface-dose measurements were taken at 2 × 2, 3 × 3, 4 × 4, 6 × 6, 8 × 8, 10 ×...

PURPOSE To compare the accuracy of 2D algorithm with an established 3D algorithm, and to define the number of CT-slices needed for treatment planning of intact breast irradiation. MATERIAL AND METHODS Twenty patients with breast cancer treated with conservative surgery were included in this study, ten of them had right breast cancer and the other 10 patients had cancer of the left breast. For...