Development of End-to-End Preclinical Treatment Verification Procedures, Traceable to NPL Air Kerma Primary Standard

Dosimetry audits are an important tool to improve quality of reported results and to support standardization of preclinical radiation research. This work presents how the combination of passive and active detectors, such as the real-time HYPERSCINT scintillation dosimetry solution, with anatomically correct mouse phantoms are adequate for the development of End-to-End dosimetry audits for the independent verification of preclinical radiation treatments.

The traceability of the detectors’ calibration to primary standards strengthens the dosimetry chain in the validation of preclinical plans, and it is consistent with the current practice for dose traceability of clinical radiotherapy treatments. Their implementation at national and regional levels could lead to databases of anonymised records, which will positively impact the dissemination of best practices and sharing of validated results.

6th Conference on small animal precision image-guided radiotherapy
Ileana Silvestre Patallo (1), Rebecca Carter (2)(3), Andrew Nisbet (2), Anna Subiel (1), Giuseppe Schettino (1) | 1. National Physical Laboratory, UK, 2. University College London, UK, 3. Cancer Institut, UK

Investigation of temperature dependence of inorganic scintillators using the HYPERSCINT research platform

The temperature dependence of four inorganic scintillation detectors was examined spectrally using the HYPERSCINT Research Platform 200 under 6 MV photon irradiations from a LINAC. After varying only the temperature of the detectors, all scintillators demonstrated linearity when the change in photon counts with temperature in the full-width at half maximum of their spectrum are integrated. Establishing the magnitude of the temperature dependence of the materials is critical to decide whether correction factors are required. This is especially true in applications such as brachytherapy, where detectors equilibrise to body temperature.

Radiation Measurements
Owen McLaughlin (1), Michael Martyn (1,2), Christoph Kleefeld (1), Mark Foley (1) | 1. Physics Unit, School of Natural Sciences, University of Galway, Galway, Ireland, 2. Galway Clinic, Doughiska, Galway, Ireland

Pre-clinical and clinical evaluation of the HYPERSCINT plastic scintillation dosimetry research platform for in vivo dosimetry during radiotherapy

The purpose of this work is to evaluate the HYPERSCINT HS-RP100 scintillation dosimetry research platform designed for clinical quality assurance (QA) for use in in vivo dosimetry measurements. The device correctly detected the treatment error when the heads were intentionally laterally shifted. In three canine clinical patients treated in multiple fractions.

J Appl Clin Med Phys. 2022
I.Schoepper (1), S.Dieterich (2), E.Alonzo Trestrail (3), M.Sean Kent (1) | Department of Radiation Oncology, University of California Davis School of Veterinary Medicine, Davis, California, USA, Department of Radiation Oncology, University of California Davis, Medical Center, Sacramento, California, USA, Pacific Crest Medical Physics, Chico, California, USA

Brachytherapy Technique Commissioning Using the HYPERSCINT Plastic Scintillation Detector

Accurate dosimetry in brachytherapy is not an easy task, as most detectors exhibit volume averaging or energy dependence reducing their usability. Free from these limitations are plastic scintillation detectors, which makes them well suited for brachytherapy applications, either for in vivo dosimetry or commissioning. This work aims to determine if the HYPERSCINT scintillation dosimetry research platform can be used for brachytherapy dose measurement in the context of commissioning a new brachytherapy technique.

2020 AAPM ANNUAL MEETING
M.Goulet, N.Octave, P.Duguay-drouin | CISSS – Chaudiere-Appalaches, Lévis, QC, CA

Characterization of a Novel Plastic Scintillator for Instant Real- Time Dosimetry in Electron FLASH-RT

Purpose was to characterize and validate the novel HYPERSCINT RP100 plastic dosimeter as a direct pulse counter and investigate its use as a real-time in-vivo dosimeter in FLASH-RT radiobiological experiments. In conclusions, the HYPERSCINT RP100 dosimeter accurately measured the delivered radiation absorbed dose under both characterization and biological experimental conditions, with a higher degree of reliability than conventional radiochromic film. Furthermore, its 500 Hz measurement frequency could directly and accurately measure the number of pulses delivered in real time. This shows its potential for real-time in-vivo dosimetry to verify accurate delivery during biological experiments and clinical treatments.

2021 COMP ANNUAL SCIENTIFIC MEETING
Y.Poirier (1), J.Xu (1), A.Ahmady (1), S.Mossahebi (1), H.Zhang (1), F.Therriault-Proulx (2), A.Sawant (1) | 1- University of Maryland School of Medicine, MD, USA , 2- McGill University, QC, Canada, 3- MEDSCINT, QC, Canada

Novel Plastic Scintillator for Online Dosimetry in Electron FLASH-RT

The accurate delivery of electrons at FLASH-RT dose rates in radiobiological experiments require new dosimeters that are capable of accurately measuring the radiation dose delivered at >0.55 Gy per pulse (>100 Gy/s) in real-time. The novel HYPERSCINT RP100 plastic dosimeter was able to accurately measure the delivered radiation absorbed dose under characterization and biological experimental conditions, with a higher degree of reliability than conventional radiochromic film. Furthermore, it was shown to directly and accurately measure the number of pulses delivered in real time. This shows potential for use as a real-time in-vivo dosimeter during biological experiments, as well as potential clinical applications.

2021 AAPM ANNUAL MEETING
Y.Poirier (1), J.Xu (1), A.Ahmady (1), S.Mossahebi (1), H.Zhang (1), F.Therriault-Proulx (2), A.Sawant (1) | 1- University of Maryland School of Medicine, Baltimore, MD, USA , 2- MEDSCINT, QC, CANADA

On the use of a single-fiber multipoint plastic scintillation detector for 192Ir high-dose-rate brachytherapy

The goal of this study was to prove the feasibility of using a single-fiber multipoint plastic scintillation detector as an in vivo verification tool during (192)Ir high-dose-rate brachytherapy treatments. The use of a multipoint plastic scintillation detector for high-dose-rate brachytherapy dosimetry is feasible. This detector shows great promise for development of in vivo applications for real-time verification of treatment delivery.

MEDICAL PHYSICS
F.Therriault-Proulx, S.Beddar, L.Beaulieu | Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA

Development of a novel multi-point plastic scintillation detector with a single optical transmission line for radiation dose measurement

The goal of this study was to develop a novel multi-point plastic scintillation detector capable of measuring the dose accurately at multiple positions simultaneously using a single optical transmission line. This study demonstrates the practical feasibility of multi-point plastic scintillation detector. This type of detector could be very useful for pre-treatment quality assurance applications as well as an accurate tool for real-time in vivo dosimetry.

PHYSICS IN MEDICINE & BIOLOGY
F.Therriault-Proulx, L.Archambault, L.Beaulieu, S.Beddar | Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA, Département de Physique, de Génie Physique et d’Optique, Université Laval, Québec, Québec, Canada, Département de Radio-Oncologie, Hôtel-Dieu de Québec, Centre Hospitalier Universitaire de Québec, Québec, Canada

Pre-Clinical and Clinical Evaluation of the HYPERSCINT Scintillation Dosimetry Research Platform

The purpose of this work is to evaluate the HYPERSCINT scintillation dosimetry research platform (Medscint Inc., Quebec City, Canada) designed for clinical QA for use in in-vivo dosimetry measurements.

2020 AAPM AM
I.Schoepper, E.Trestrail, S.Dieterich, M.Kent | WR Pritchard Veterinary Medical Teaching Hospital, UC Davis School of Veterinary Medicine UC Davis School Of Veterinary Medicine, Pacific Crest Medical Physics ,Chico, CA, UC Davis Medical Center, Sacramento, CA, Surgical and Radiological Sciences, UC Davis School of Veterinary Medicine, Davis, CA

Evaluation of scintillation detectors for ultrahigh dose-rate x-ray beam dosimetry

FLASH-Radiotherapy is an emerging ultrahigh dose rates radiotherapy technique, and animal studies have demonstrated the safety and efficacy of the technique in cancer treatment. A reliable real-time dosimeter system is crucial for the characterization of the so-called ‘FLASH-effect’, and an accurate beam delivery. This study aims to benchmark the performance of optical fiber inorganic scintillating detectors (ISDs) with plastic scintillating detectors (PSDs) for an ultrahigh dose-rate x-ray beam irradiation. Measurements includes : relative scintillator output, signal linearity with dose and dose rate, signal-to-noise ratio (SNR), signal stability and reliability.

The PSDs resulted in the highest reliability for a UHDR beam measurement with a CV of <0.1% while the Gd2O2S:Tb showed excellent repeatability (coefficient of variation (CV) <0.1%) compared to other detectors. All detectors showed good linearity with tube current (R2 < 0.975) and shutter exposure (R2 >0.999).

Proc Spie
Shahirah Shaharuddin (1), Alexander Hart (2), Magdalena Bazalova-Carter (2), Luc Beaulieu (3), Cloe Giguere (3), Christoph Kleefeld (1), Mark J. Foley (1) | 1. National University of Ireland, Galway (Ireland), 2. University of Victoria (Canada), 3 University Laval (Canada)