BACKGROUND This study was designed to evaluate the integral dose (ID) received by normal tissue from intensity-modulated radiotherapy (IMRT) for prostate cancer. METHODS AND MATERIALS Twenty-five radiation treatment plans including IMRT using a conventional linac with both 6 MV (6MV-IMRT) and 20 MV (20MV-IMRT), as well as three-dimensional conformal radiotherapy (3DCRT) using 6 MV (6MV-3DCRT)...

ID: 4805 Title: For small field Radiosurgery Intermediate Energy Photons (800kV) show superior dose distributions compared to megavoltage beams Purpose: Beam penumbra is significant when using stereotactic radiosurgery to treat small volumes with limited microscopic extensions. It is challenging to irradiate these lesions if a highly critical structure is in close contact with the target. Previ...

BACKGROUND Gold nanoparticles are emerging as promising agents for cancer therapy and are being investigated as drug carriers, photothermal agents, contrast agents and radiosensitisers. OBJECTIVE The aim of this study is to understand characteristics of secondary electrons generated from interaction of gold nanoparticles GNPs with x-rays as a function of nanoparticle size and beam energy and ...

ID: 3490 Title: Non-Tumor Integral Dose in Conformal, External Beam Radiation Therapy Purpose: To investigate the computed non-tumor integral dose (NTID) delivered during treatment of prostate cancer with intensity modulated radiotherapy (IMRT) compared to three-dimensional conformal radiotherapy (3DCRT). Low and highenergy photon treatments were also evaluated in this study, as was helical tom...

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...

The analytical anisotropic algorithm (AAA) was implemented in the Eclipse (Varian Medical Systems) treatment planning system to replace the single pencil beam (SPB) algorithm for the calculation of dose distributions for photon beams. AAA was developed to improve the dose calculation accuracy, especially in heterogeneous media. The total dose deposition is calculated as the superposition of the...

introduction in this study, we aimed to assess the medium-term energy stability of a 6mv elekta compacttm linear accelerator. to the best of our knowledge, this is the first published article to evaluate this linear accelerator in terms of energy stability. as well as investigating the stability of the linear accelerator energy over a period of several weeks, the results will be useful for esti...

Introduction: Physical wedge as a useful tool has been utilized in radiotherapy to modify photon beam shape and intensity such that it distributes dose uniformly in tumor site and reduces hot points. Since during Linac commissioning dosimetric parameters like output factors and lateral dose profiles are measured only for symmetric open and wedged fields, so calculation the par...

Background: Commissioning tests are recommended before implementing Intensity Modulated Radiation Therapy. This study evaluated five different plans of IMRT mocks for different modulation indices. Materials and Methods: IMRT tests were done in slab phantom for both 6MV and 15 MV photon energies using a 2D array ion chamber dosimeter. Results: The acceptance criteria were based on 3% /3mm. All t...

Background: External beam radiation therapy is often administered to patients implanted with silicone gel breast prosthesis. The aim of this study was to investigate the influence of silicone gel breast prosthesis on photon dose distributions. In the event of recurrence, the oncologist may be forced to irradiate through the prosthetic device. To quantify the dose enhancement or reduction below ...