Due to the size of the targeted regions of interest (ROI), IGSARTP are designed to deliver very small, individual, or combined treatment fields. These devices are capable of delivering realistic radiotherapy plans with beams in the medium-energy X-ray range (0.5–4 mm Cu, in terms of Half Value Layer (HVL)). Targeted preclinical irradiations are mostly performed using dedicated Image-Guided Small Animal Radiotherapy Platforms (IGSARTP). ![]() Research performed in those scenarios has the potential to translate into improvements in clinical outcomes. The use of preclinical irradiators with image-guidance capabilities, combined with in vivo (tumour) models embedded in mice, offers unique possibilities to cross-examine the radiotherapy response of tumours and normal tissues. They are critical to the development of personalized and precision medicine and its translational success. Preclinical studies are able to accurately model biological and physical aspects of clinical scenarios in radiation oncology. It supports the development of procedures for independent “live” dose verification of complex preclinical radiotherapy plans with the possibility to insert the detectors in phantoms. We demonstrated that when the detector is cross-calibrated in the user’s beam, it is a useful tool for dosimetry in medium-energy X-rays with small fields delivered by Image-Guided Small Animal Radiotherapy Platforms. Compared with EBT3 films and CMOS, ROF was within 5% (except for smaller circular fields). Independently of the beam quality, the scintillator signal repeatability was adequate and linear with dose. Relative output factors (ROF) for small, collimated fields (≤10 mm × 10 mm) were measured and compared with Gafchromic film and to a CMOS imaging sensor. Absorbed dose quality-dependent calibration coefficients, based on a cross-calibration against air kerma secondary standard ionization chambers, were determined. The response’s variation with temperature and beam angle incidence was also evaluated. Dose rate, linearity, and repeatability of the response (among others) were assessed for medium-energy X-ray beam qualities. ![]() The purpose of the study was to characterize a detection system based on inorganic scintillators and determine its suitability for dosimetry in preclinical radiation research. We demonstrated the suitability of the inorganic scintillation system for the development of phantom-based end-to-end tests for dose verification in newly implemented preclinical radiotherapy irradiation techniques. Additionally, we determined relative output factors for very small fields and compared them to other measurement systems (EBT3 film and CMOS sensor). ![]() ![]() We implemented a cross-calibration framework based on international dosimetric protocols to assess the energy dependence of the detector. In this paper, we carried out a dosimetric characterization of an active detection system based on inorganic scintillators in medium-energy X-rays. This results in the inconvenient task of lengthy post-processing. Except for dose reference measurements, dosimetric quality control of image-guided small animal irradiation platforms is mostly performed with passive detectors (alanine and gafchromic films). Dosimetry for preclinical radiotherapy research requires the standardization of dose validation and quality assurance procedures.
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