Gafchromic XRCT, radiochromic film is assessed over a broad energy range, from kilovoltage to megavoltage x rays for variations in reflected optical density to dose response. A large energy dependence was found with reflected optical density output for the same delivered dose varying from 7.8±0.35 at 25.5keV (50kVp) peaking at 12.1±0.5 at 54keV (125kVp) to 0.975±0.03 at 2300keV (10MV) when norm...

Megavoltage electron beams represent an important treatment modality in modern radiotherapy, often providing a unique option in the treatment of superficial tumours (less than 5 cm deep). Electrons have been used in radiotherapy since the early 1950s, first produced by betatrons and then by microtrons and linacs. Modern high energy linacs typically provide, in addition to two megavoltage photon...

This study proposes a new method for removal of metal artifacts from megavoltage cone beam computed tomography (MVCBCT) and kilovoltage CT (kVCT) images. Both images were combined to obtain prior image, which was forward projected to obtain surrogate data and replace metal trace in the uncorrected kVCT image. The corrected image was then reconstructed through filtered back projection. A similar...

disease tends to recur in a treated field with a frequency which is inversely related to dose and approaches zero at a dose of approximately 4000 rads, delivered at the rate of about 1000 rads/week. Such doses make the use of megavoltage X-ray beams mandatory to avoid severe skin reactions, but are other wise well tolerated by the normal tissues. The inverse relation ship of recurrence rate to ...

Micelle gel is a radiochromic hydrogel with the potential to be used as a three dimensional (3D) radiation dosimeter. Since an ideal dosimeter should present water equivalent properties, in this study the water equivalence of two formulations of micelle gel has been investigated by calculating electron density, effective atomic number, fractional interaction probabilities, mass attenuation coef...

The energy dependence of the dose response of EBT Gafchromic film is assessed over a broad energy range, from superficial to megavoltage X-rays. The film is auto-developing and sensitive, it provides accurate dose assessment of low doses (about 1-2 Gy) used in radiotherapy. The energy dependence of the response of EBT film was found to be very weak: the variations do not exceed 10% over the ran...

The purpose of this study was to evaluate the effect of resveratrol on cytogenetic damages of iododeoxyuridine (IUdR) and x-ray megavoltage radiation (6 MV) in spheroid model of U87MG glioblastoma cancer cell line using clonogenic and alkaline comet assay. Cells were cultured as spheroids (350 µm) that were treated with 20 μM resveratrol, 1 μM IUdR and 2 Gy of 6 MV x-ray. After treatment, viabi...