Dose Imaging in radiotherapy photon fields with Fricke and Normoxic-polymer Gels

Gel dosimetry measurements and Monte Carlo modeling for external radiotherapy photon beams

“…3a), it is possible to compare relative dose distributions with normalized DOD [1,4]. Typical normalized DOD distribution surfaces are shown in Fig.…”

“…However, greater Fricke gel dosimeters are actually under study [9] in order to establish the feasibility of employing wider field sizes, as those commonly used in radiotherapy. …”

“…A Fricke (ferrous sulfate) solution infused with Xylenol Orange was incorporated to a gel matrix (porcine skin gelatin) as described in Refs. [1,[4][5][6][7]. The solution was introduced in properly designed polystyrene layers.…”

“…The analysis method is based on optical light-transmittance detection [1,4], performing before and after phantom exposure dosimeter images by means of a commercial flatbed-like scanner. Suitably developed software, written in MatLab s , traduces the dosimeter images into optical density differences (DOD), which normalized can be compared with relative dose distributions or, eventually, employing appropriate calibration factors, with absolute dose distributions [1,4].…”

“…Suitably developed software, written in MatLab s , traduces the dosimeter images into optical density differences (DOD), which normalized can be compared with relative dose distributions or, eventually, employing appropriate calibration factors, with absolute dose distributions [1,4]. In order to ensure linearity between DOD and dose distributions, it is necessary to analyze the scanner response studying characteristics like illumination homogeneity and reproducibility.…”