Introduction: Intensity modulated radiation therapy (IMRT) and three-dimensional conformal radiation therapy (3D CRT) are two treatment modalities in prostate cancer, which provide acceptable dose distribution in tumor region with sparing the surrounding normal tissues. IMRT is based on inverse planning optimization; in which, intensity of beams is modified by using multileaf c...

background: inclusion of inhomogeneity corrections in intensity modulated small fields always makes conformal irradiation of lung tumor very complicated in accurate dose delivery. objective: in the present study, the performance of five algorithms via monte carlo, pencil beam, convolution, fast superposition and superposition were evaluated in lung cancer intensity modulated radiotherapy planni...

The purpose of this study was to evaluate different homogeneity indices for IMRT of head and neck cancers and to suggest the best representative homogeneity index for quantitative measure of dose homogeneity. In this study 3 different homogeneity indices were evaluated for 22 head and neck cancer patients receiving dynamic IMRT treatments on Clinac-DHX linear accelerator with 6 MV photon beam. ...

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: To date, different kinds of treatment methods have been proposed for radiotherapy of cancer patients. Choosing the kind of treatment method affects the quality of the patient's treatment. This study aims to investigate the effect of the number of radiation treatment sessions on the dose received by the patient and the distribution of tumor dose and dose received by organs at risk in...

Diagnostic reference levels (DRLs) are an important optimisation tool, which aid in identifying abnormally high dose levels. These are currently not available in Saudi Arabia, and this research aims to remedy this. CT dose data (DLP and CTDIvol) were collected for a minimum number of 10 adult patients of average size (60-80 kg) presenting for a range of CT examinations from public hospitals in ...

background: natural background radiation of a particular region is one of the distinctive factors defining the status of environment. eloor island is an industrial area in ernakulum district of the state of kerala, india. the indoor and outdoor gamma level measurements have been carried out for the region for evaluating the annual effective dose to the population residing in this area. material...

introduction: this study was designed to evaluate dosimetric parameters such as rectal dose, bladder dose, integral dose (id), homogeneity index (hi) and conformity index (ci) in various treatment plans for prostate cancer. materials and methods: pelvic computed tomography (ct) scans of 27 patients were acquired and transferred to the rtdoseplan treatment planning system. for each patient, 8 co...