Introduction: During radiotherapy, high accuracy in the dose delivery is required because there is a strong  relationship between the absorbed dose, local tumor control and particularly the normal tissue damage. In  many institutions, in vivo dosimetry using diodes is performed to check the actual dose delivered. In general,  the uncertainty in the dose delivered should fall within  ± 5% of the...

introduction the gamma knife system is designed solely for non-invasive treatment of brain disorders, and it benefits from stereotactic surgical techniques. dose calculations required in the system are performed by gammaplan code; in this code, brain tissue is considered uniform. in the present study, we evaluated the effect of gamma knife system on the obtained dose through simulating a real h...

background: delivering the maximum dose to tumor while achieving the minimum dose delivery to normal tissue; is the most important goal in external radiotherapy. diode in vivo dosimetry is widely considered to be an important tool for quality improvement of patient care in external radiotherapy. uncertainty in dose delivery should fall within 5% of the prescribed dose as recommended by internat...

Introduction: Accelerated Partial Breast Irradiation (APBI) is an effective treatment for breast carcinomas because of its limited number of fractions. Strut-adjusted volume implant (SAVI) is a HDR brachytherapy applicator to deliver the prescription dose with good PTV coverage and acceptable dose to skin, chest wall and organ at risks. Acceptable clinical outcomes depend on a...

Introduction The Gamma Knife system is designed solely for non-invasive treatment of brain disorders, and it benefits from stereotactic surgical techniques. Dose calculations required in the system are performed by GammaPlan code; in this code, brain tissue is considered uniform. In the present study, we evaluated the effect of Gamma Knife system on the obtained dose through simulating a real ...

Background: The advantages of proton beam in radiation therapy- like small lateral scattering as well as absence of exit dose tail in the organs which are after the tumor- make it capable of delivering more treatment doses to the target and much lesser to the critical tissues near it. Materials and Methods: In this study, the Monte Carlo MCNPX code has been used to simulate a slab head phantom ...

Introduction: Wedge filters are used in radiotherapy to modify photon beam and improve dose uniformity in the target volume. Determination of wedge dose distribution is important to improve treatment planning accuracy. The utilization of treatment planning software to obtain dose distribution is not always available. In this work an analytical model has been developed to calcu...

Background: Neutron contamination in our environment can cause harmful biological effects on human body. Therefore, many efforts have been made to construct a neutron dosimeter to estimate the received dose. Objective: To design a simple neutron dosimeter. Methods: The primary dosimeter had 3He as a spherical thermal neutron detector encircled by paraffin 10 cm in radius. Then, the paraffin sph...

The principal objective of radiation protec­tion is to ensure that the dose received by any individual does not exceed the applicable M.P.D. values.We will discuss in this paper the presents recommendations and technical information related to the design and installation of struc­tural shielding with taking into account the concept of Maximum Permissible Dose equi­valent (MPDl as expressed and ...

BACKGROUND Intraoperative Radiotherapy (IORT) is a method by which a critical radiation dose is delivered to the tumour bed immediately after surgical excision. It is being investigated whether a single high dose of radiation will impart the same clinical benefit as a standard course of external beam therapy. Our centre has four Photon Radiosurgery Systems (PRS) currently used to irradiate brea...