Dose response and stability of silicone-based deformable radiochromic dosimeters (FlexyDos3D) using spectrophotometer and flatbed scanner

This study investigated the dose response and stability of dose-rate independent silicone-based radiochromic dosimeters (FlexyDos3D), which exhibit substantial potential in fabricating deformable anthropomorphic phantoms for radiotherapy dosimetry. The dose response induced optical absorption changes and stability were investigated using two readout modalities: a UV-VIS spectrophotometer and a flatbed scanner. The absorption spectral measurement in the visible wavelength of 400 nm - 700 nm showed a principle absorption peak at 626 nm, a secondary peak at 424 nm and a valley area with minimal absorption in between around 470 nm. Dose response showed strong linearity between 0 and 90.3 Gy. The dose response stability was determined by measuring optical absorptions at various times. The phenomena of increase in dosimeters' optical density background (creep-up effect) and decrease in irradiated dosimeters’ optical density (fading effect) were identified, and these two effects can be well depicted by a proposed dual-component model. Dose gradient integrity was assessed by measuring changes in optical absorption profiles that were formed by sharp dose-falloff. The time-dependent profiles indicated that the dose gradient integrity diminished fast over time.
Source: Radiation Physics and Chemistry - Category: Physics Source Type: research

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Source: Journal of the Optical Society of America A - Category: Physics Authors: Source Type: research
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Source: The American Journal of Surgical Pathology - Category: Pathology Tags: Original Articles Source Type: research
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Source: Microbial Pathogenesis - Category: Infectious Diseases Source Type: research
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Source: Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology - Category: ENT & OMF Source Type: research
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Source: Progress in Natural Science: Materials International - Category: Materials Science Source Type: research
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