Successful delivery of conformal fields requires stringent immobilization and treatment verification, as well as knowledge of the setup reproducibility. [1] Before coming OBI, electronic portal imaging detector was used to detect the setup errors. EPID images are not clear vision to identify correctly and immediately because they were produced by megavoltage X-ray during treatment setup. In OBI...

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...

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 ...

Gafchromic XR type-R radiochromic film is a relatively new product designed for use at clinical diagnostic x-ray energies both qualitatively and quantitatively. This short note investigates the energy response characteristics of this high-sensitivity radiochromic film for both diagnostic and therapeutic x-ray energies. Results are also compared to conventional silver halide x-ray film for energ...

Since the inception of radiotherapy soon after the discovery of X rays by Roentgen in 1895, the technology of X ray production has first been aimed towards ever higher photon and electron beam energies and intensities, and more recently towards computerization and intensity modulated beam delivery. During the first 50 years of radiotherapy the technological progress was relatively slow and main...

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...