Field output correction factors using a fully characterized plastic scintillation detector (HYPERSCINT RP-200)

Commissioning, SMALL-FIELD, MeV Electron, MV Photon, Commissioning, Detector comparaison, Energy Dependency, Monte Carlo, Quality Assurance Show more

As small fields become increasingly important in radiation therapy, accurate dosimetry is essential for ensuring precise dose calculation and treatment optimization. Despite the availability of small volume detectors, small field dosimetry remains challenging. The new plastic scintillation detector (PSD) from the HYPERCINT RP-200 platform from Medscint offers a promising solution with minimal correction requirements for small field measurements.

This study focused on characterizing the field output correction factors of the PSD across a wide range of field sizes and demonstrating its potential for determining correction factors for other small field detectors. Monte Carlo simulations and experimental comparisons were used to assess the system’s performance. The PSD exhibited near-unity correction factors (1.002 to 0.999) across field sizes between 0.6×0.6 cm² and 30×30 cm², with an impressive total uncertainty of 0.5%.

The PSD is shown to be a highly accurate and reliable detector for small field dosimetry, and it can also be used to determine correction factors for other dosimeters with great precision.

PREPRINT
Luc Gingras (1,2), Yunuen Cervantes (1,2,3), Frederic Beaulieu (1,2), Magali Besnier (1,2), Benjamin Coté (4), Simon Lambert-Girard (4), Danahé LeBlanc (4), Yoan LeChasseur (4), François Therriault-Proulx (4), Luc Beaulieu (1,2,3), Louis Archambault (1,2,3) | 1. CHU de Québec–Université Laval, Québec – Canada, 2. Centre de recherche du CHU de Québec, Québec – Canada, 3. Université Laval, Québec – Canada, 4. Medscint, Québec – Canada

Characterization of a novel time-resolved, real-time scintillation dosimetry system (HYPERSCINT RP-FLASH) for ultra-high dose rate radiation therapy applications

FLASH-RT, MeV Electron, Beam characterization, Commissioning, Detector comparaison, Energy Dependency, LINAC Pulse Counting, Quality Assurance, Real-time Dosimetry Show more

This study evaluates a novel scintillation dosimetry solution developed by Medscint for ultra-high dose rate (UHDR) radiotherapy, the HYPERSCINT RP-FLASH. The system was tested on an UHDR electron beamline, demonstrating dose linearity and independence from dose rate (1.8–1341 Gy/s) and dose per pulse (0.005–7.68 Gy) within ±3% tolerance. The system accurately measured doses per pulse up to 120 Hz.

With daily calibrations and specific correction factors, the system provides real-time, millisecond-resolved dosimetric measurements for pulsed conventional and UHDR beams, showing promise for applications in FLASH-RT.

PREPRINT
Alexander Baikalov (1,2,3), Daline Tho (1), Kevin Liu (1,4), Stefan Bartzsch (2,3), Sam Beddar (1,4), Emil Schüler (1,4) | 1. University of Texas MD Anderson Cancer Center, Houston, TX – USA, 2. Technical University of Munich – Germany, 3. German Research Center for Environmental Health, Neuherberg – Germany, 4. The University of Texas MD Anderson Cancer Center UTHealth Houston Graduate School of Biomedical Sciences, Houston, TX – USA

Characterization of a 0.8 mm³ Medscint Plastic Scintillator Detector System for Small Field Dosimetry

SMALL-FIELD, MeV Electron, Advanced Optical Dosimetry, Angular dependancy, Beam characterization, Detector comparaison, Energy Dependency, Quality Assurance Show more

The scintillator-based dosimetry system HYPERSCINT RP-200, coupled with a 0.8 mm³ plastic scintillator detector, demonstrated excellent dosimetric properties for small field radiation therapy, including good repeatability, dose linearity, and accuracy down to field sizes as small as 0.5 × 0.5 cm².

Physics in Medicine & Biology
Elena Timakova (1,2), Magdalena Bazalova-Carter (1) , Sergei Zavgorodni (2) | 1. University of Victoria, British Columbia, Canada, 2. BC Cancer Agency, Vancouver Island Centre, British Columbia, Canada

Performance of the HYPERSCINT scintillation dosimetry research platform for the 1.5 T MR-linac

MR-LINAC, Treatment Plan QA, MV Photon, Adaptive RT, Angular dependancy, Detector comparaison, Energy Dependency, Quality Assurance, Real-time Dosimetry Show more

This study demonstrates the suitability of the HYPERSCINT PSD for accurate time- resolved dosimetry measurements in the 1.5 T MR-linac. The excellent performance during continuous MR scanning and during dynamic movement indicates the great potential of the detector to validate end-to-end workflows of online adaptive radiotherapy

PHYSICS IN MEDICINE & BIOLOGY
Prescilla Uijtewaal (1), Benjamin Côté (2), Thomas Foppen (1), J H Wilfred de Vries (1), Simon J Woodings (1), Pim T S Borman (1), Simon Lambert-Girard (2), François Therriault-Proulx (2), Bas W Raaymakers (1), Martin F Fast (1) | 1 – UMC Utrecht, Netherland, 2 – Medscint, Canada

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

Advanced Optical Dosimetry, Brachytherapy, Fundamental research, In Vivo Dosimetry, MV Photon, Advanced Optical Dosimetry, Detector comparaison, Fundamental Research, Real-time Dosimetry Show more

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

Use of a Commercial Plastic Scintillation Detector for Determination of Detector-Specific Small Field Output Correction Factors of Other Detectors

SMALL-FIELD, MV Photon, Commissioning, Detector comparaison, Monte Carlo, Quality Assurance Show more

The goal of this work is to determine small field output correction factors of various detectors using the HYPERSCINT plastic scintillation detector as a reference and to compare values with current available data. The simple and well understood composition and geometry of the scintillation detector make it ideal to be used as a reference detector for the evaluation of field output correction factors. Field size dependent correction factors have been extracted for different detectors and show limited discrepancies with current available data. This may potentially be attributed to inter detector variability or other methodological uncertainties in published data.

2022 AAPM ANNUAL MEETING
M.Besnier (1), F.Beaulieu (1), F.Berthiaume (1,2), Y.Cervantes Espinosa (1), B.Côté (2), S.Lambert-girard (1,2), D.Leblanc (1,2), Y.Lechasseur (2), F.Therriault-Proulx (2), L.Archambault (1), L.Beaulieu (1), L.Gingras (1) | 1- CHU de Quebec – Universite Laval, QC, Canada, 2- MEDSCINT, QC, Canada

Comparison Between the HYPERSCINT RP200 Scintillation Detector and Other Small Field Detectors for 10MV FFF SRS Beam Modelling On a VersaHD Linear Accelerator

Commissioning, SMALL-FIELD, MV Photon, Angular dependancy, Beam characterization, Commissioning, Detector comparaison, Energy Dependency, Quality Assurance Show more

Plastic scintillation detectors (PSDs) have advantageous dosimetric properties, including small size and energy independence, which make them ideal candidates for small field dosimetry.

2021 AAPM ANNUAL MEETING
J.Morin, JF.Cabana, M.Goulet, D.Theriault | CISSS – Chaudiere-Appalaches, Lévis, QC, CA

Technical note: Characterization and practical applications of a novel plastic scintillator for online dosimetry for an ultrahigh dose rate (FLASH)

FLASH-RT, MeV Electron, Commissioning, Detector comparaison, Rabiobiology, Real-time Dosimetry Show more

Although FLASH radiation therapy is a promising novel technique, the ultrahigh pulsed dose rates mean that experimental dosimetry is very challenging. The plastic scintillator shows a linear and reproducible response and is able to accurately measure the radiation absorbed dose delivered by 16-MeV electrons at UHPDR. The dose is measured accurately in real time with a greater level of precision than that achieved with a radiochromic film.

Med Phys. 2022
Y.Poirier (1,2), J.Xu (1), S.Mossahebi (1), F.Therriault-Proulx (3), A.Sawant (1) | 1- Department of Radiation Oncology, University of Maryland School of Medicine, Maryland, USA, 2- Department of Medical Physics, McGill University, Quebec, Canada, 3- MEDSCINT, Quebec, Canada

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

Treatment Plan QA, MV Photon, Detector comparaison, Phantom QA, Quality Assurance Show more

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

Brachytherapy Technique Commissioning Using the HYPERSCINT Plastic Scintillation Detector

Brachytherapy, Commissioning, In Vivo Dosimetry, kV Photon, Commissioning, Detector comparaison, Quality Assurance Show more

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