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

Patient Specific QA for External Beam Radiotherapy Using the HYPERSCINT Plastic Scintillation Detector

Plastic scintillation detectors have interesting dosimetric properties, including small size and energy independence. These advantages make them well suited for VMAT patient-specific QA, either alone or in conjunction with a detector matrix. This work aims to determine if the HYPERSCINT scintillation dosimetry research platform can replace the classic ion chamber in a clinical patient-specific QA workflow.

2020 AAPM AM
M.Goulet | CISSS – Chaudiere-Appalaches, Lévis, QC, CA

Characterization of the HYPERSCINT Dosimetry System for Real-Time Dosimetry Measurements with the Varian TrueBeamLinac

Plastic scintillator/optical fibre dosimetry systems are advantageous due to their near water equivalence, waterproof construction, linear dose response, and good spatial resolution due to their small size. The nanosecond decay times of plastic scintillators enable the possibility of real-time dosimetry. We tested the new HYPERSCINT fibre detector system to determine if, in addition to the expected dose and field size responses, this system can provide real-time dose information. The HYPERSCINT system is suitable after appropriate calibration to be used to measure relative dose delivered in cGy as well as indicate changing dose conditions within 0.3 seconds.

2020 AAPM AM
C.Penner (1,2), C.Hoehr (2), C.Mendez (1), C.Duzenli (1) | BC Cancer, Vancouver, BC, CA, TRIUMF, Vancouver, BC, CA

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

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

Beam matching for small-field dosimetry applications using accelerator solenoid current and a miniature plastic scintillation detector.

The goal of this work is to determine the optimal accelerator solenoid current (ASOL) that minimizes the spread of measured small field output factor (OF) values between a series of machines. Small field OF measurements of 6 MV flattening filtered beams from 3 Varian TrueBeam linear accelerators were performed using a 1 mm diameter by 1 mm length plastic scintillation detector HYPERSCINT HS-RP200 research platform. In conclusion Small field dosimetry characteristics are highly sensitive to beam focal spot size. and the possibility to optimize accelerator focusing coil current to reduce OF and penumbra width spread enables new avenues in beam matching of series of machines, especially for SRS and SBRT techniques.

2022 COMP ANNUAL SCIENTIFIC MEETING
L.Gingras (1), F.Beaulieu (1), M.Besnier (1), B.Côté (2), D.Leblanc (2), L.Beaulieu (1), L.Archambault (1) | 1- CHU de Québec – Université Laval, QC, CA, 2- MEDSCINT, QC, CA

Plastic Scintillation Detector for Dosimetric Characterization of Mobetron Ultra-High Dose Rate Electron Beam

The purpose is to present commissioning data for the MOBETRON electron radiation therapy system (IntraOp) at ultra-high dose rate using the HYPERSCINT plastic scintillation detector. The suitability of using a plastic scintillator as an active dosimeter for commissioning measurements of an ultra-high dose rate electron beam has been demonstrated (reference dosimetry, DPP, beam penetration, linearity with number of pulses, linearity with PW and short-term output stability).

2022 AAPM ANNUAL MEETING
G.Famulari (1), K.Zerouali (1), O.Piron (1), JF.Aubry (1), F.DeBlois (1), JF.Carrier (2) | 1- Centre Hospitalier de l’Universite de Montreal (CHUM), Montreal, QC, CA, 2- Departement de Physique, Universite de Montreal, Montreal, QC, CA

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

Small field dosimetry of a Varian TrueBeam High Definition MLC linear accelerator using theHyperscint RP200 scintillation detector.

Small field dosimetry of a Varian TrueBeam High Definition MLC linear accelerator using the Hyperscint RP200 scintillation detector.

Purpose: To evaluate the performance of the new Hyperscint RP200 plastic scintillator for small field measurements of a Varian TrueBeam linear accelerator in comparison with the current state-of-the-art methodology in the clinic.

Methods: Small field measurements were performed using different detectors: a diamond detector (microDiamond, PTW), a diode (Razor, IBA), a compact ion chamber (Razor, IBA), and a 1mm x 1mm
plastic scintillation detector (Hyperscint RP200, Medscint). Correction factors based on measured field sizes, following TRS483 recommendations, were applied to all measurements. Output factors of a
TrueBeam linear accelerator were measured for field sizes of 0.5 cm to 2 cm for jaws and MLC configurations for 6-MV, 6-MV FFF and 10-MV FFF photon beams. Output factors for different circular collimators (0.4 cm to 2 cm) were also obtained at 10-MV FFF. Scintillator measurements were compared to the small-field dosimetry methodology used clinically.

Results: No correction factors were necessary for the plastic scintillation detector measurements. Scintillator measurements were within 1.1% of the standard methodology for all the small field geometries studied. Average relative differences were (0.3±0.5)%, (0.7±0.3)%, and (0.2±0.2)% for the 6-MV, 6-MV FFF, and 10-MV FFF, respectively. Output factors of circular field sizes down to 0.4-cm diameter were obtained with an average relative difference of (0.1±0.4)%, including a maximum difference of 0.7% for the smallest field.

Conclusion: This new scintillation dosimetry research platform shows great promises for small field dosimetry. It has the potential to be used as part of a single-detector no-correction-factor methodology.

2021 COMP ASM
L.Gingras, B.Côté, F.Berthiaume, S.Lambert-Girard, D.Leblanc, L.Archambault, L.Beaulieu, F.Therriault-Proulx | CHU de Quebec – Universite Laval, QC, CA, Département de radio-oncologie et Axe Oncologie du CRCHU de Québec, QC, CA, MedScint, QC, CA