background: boron neutron capture therapy (bnct) is a radiotherapy that combines biological targeting and high linear energy transfer. a potential therapeutic approach for non-small cell lung cancer (nsclc) is considered. however, dose in lung tumor is not homogeneous, and it will reduce the effect of bnct treatment. in order to improve the dose distribution of bnct, the multi-field irradiation...

Background: In radiation therapy, peripheral dose or the dose outside the radiotherapy field, is important when anatomical structures with very low dose tolerances are involved. One of these critical organs in pelvic irradiation is testis. The amount of radiation delivered to the testes in radiotherapy must be kept as small as possible, consistent with the limit dose of this organ. The threshol...

Introduction: During intensity modulated radiation therapy (IMRT) technique, theoretically, presence of flattening filter (FF) across the beamline of clinical linear accelerator (linac) is not essential to obtain uniform lateral profiles due to intensity modulation of photon beams by multileaf collimators (MLCs). The aim of this study was to investigate the dosimetrical propert...

Background: During intensity modulated radiation therapy (IMRT) technique, theoretically, presence of flattening filter (FF) across the beamline of clinical linear accelerator (linac) is not essential to obtain uniform lateral profiles due to intensity modulation of photon beams by multileaf collimators (MLCs). The aim of this study was to investigate the dosimetrical properties of 18 MV photon...

background: in radiation therapy, peripheral dose or the dose outside the radiotherapy field, is important when anatomical structures with very low dose tolerances are involved. one of these critical organs in pelvic irradiation is testis. the amount of radiation delivered to the testes in radiotherapy must be kept as small as possible, consistent with the limit dose of this organ. the threshol...

background: dose calculation algorithms play a very important role in predicting the explicit dose distribution. we evaluated the percent depth dose (pdd), lateral depth dose profile, and surface dose volume histogram in inhomogeneous media using calculation algorithms and inhomogeneity correction methods. materials and methods: the homogeneous and inhomogeneous virtual slab phantoms used in th...

Aims: It was aimed to investigate postoperative conformal radiotherapy planning that provides the best target volume and the least dose for critical organs in cancers of stomach. Methods: This study was conducted on the CT simulation images of thirty patients diagnosed with gastric cancer. Target volumes and the organs at risk were contoured. AP-PA reciprocal parallel field conventional plan an...

Introduction Wedge modifiers are commonly applied in external beam radiotherapy to change the dose distribution corresponding to the body contour and to obtain a uniform dose distribution within the target volume. Since the radiation dose delivered to the target must be within ±5% of the prescribed dose, accurate dose calculation by a treatment planning system (TPS) is important. The objective ...

Dose profiles produced by wedge filters in the non-wedged direction can exhibit a 7% or greater dose reduction at the outer ends of the field compared with open field profiles. However, many planning systems use open field profiles to model wedged dose distributions. In the present work, wedges have been modified to reproduce open field profile shapes. This modification involved removing varyin...