Novel Plastic Scintillator for Online Dosimetry in Electron FLASH-RT

4. FLASH-RT / UHDR, 5. In Vivo Dosimetry, MeV Electron, Energy Dependency, LINAC Pulse Discrimination, Rabiobiology, Real-time Dosimetry Show more

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

Investigation of the HyperscintTM Plastic Scintillation Dosimetry System Performance in a 15 MeV electron beam at FLASH dose rates

4. FLASH-RT / UHDR, MeV Electron, Energy Dependency, Real-time Dosimetry Show more

The performance of the HYPERSCINT plastic scintillation dosimetry system in a 15 MeV electron beam operating at FLASH dose rates was investigated. The linac produced a 15 MeV electron FLASH beam with an average dose rate of ~250 Gy/s and dose per pulse between 1 Gy and 1.7 Gy, at the level just above the multi-leaf collimator. The HYPERSCINT plastic scintillator detector system agreed with OSLDs within 3.5% for 10 to 20 pulse FLASH deliveries using the standard dose rate calibration for both dosimeters.

2021 COMP ANNUAL SCIENTIFIC MEETING
C.Mendez, P.Petric, T.Karan, C.Duzenli | BC Cancer, Vancouver, BC, CA

EFLASH Dosimetry On a Conventional Linac Using Pulse-Gated Delivery

4. FLASH-RT / UHDR, 9. Advanced Dosimetry, MeV Electron, Detector comparaison, Energy Dependency, Fundamental Research, LINAC Pulse Discrimination, Real-time Dosimetry Show more

To build on previous experiments and improve reproducibility of electron FLASH delivery on a conventional linear accelerator, a pulse-gating circuit was constructed and tested with several dosimeters including : a 0.01cc volume ion chamber, optically stimulated luminescence dosimeters (OSLDs), Gafchromic MD film and a novel plastic scintillation detector with spectral analysis (HYPERSCINT).

2021 AAPM ANNUAL MEETING
C.Duzenli, C.Mendez, M.Petric, J.Sweeney, D.Ta, T.Karan | BC Cancer, Vancouver, BC, CANADA

On the nature of the light produced within PMMA optical light guides in scintillation fiber-optic dosimetry

9. Advanced Dosimetry, MeV Electron, MV Photon, Advanced Optical Dosimetry, Cherenkov, Energy Dependency, Fundamental Research Show more

The goal of this study was to evaluate the nature of the stem effect light produced within an optical fiber, to quantify its composition, and to evaluate the efficiency of the chromatic technique to remove the stem effect. The chromatic stem effect removal technique is accurate in most of the situations. However, noticeable differences were obtained between very specific high-energy irradiation conditions. It would be advantageous to implement an additional channel in the chromatic stem effect removal chain or implement a spectral approach to independently remove the Cerenkov and the fluorescence components from the signal of interest. This would increase the accuracy and versatility of the actual chromatic stem effect removal technique.

PHYSICS IN MEDICINE & BIOLOGY
F.Therriault-Proulx (1)(2), L.Beaulieu (2)(3), L.Archambault (2)(3), S.Beddar (4)(1) | 1- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA, 2- Département de Physique, de Génie Physique et d’Optique, Université Laval, Québec, Québec, Canada, 3- Département de Radio-Oncologie, Hôtel-Dieu de Québec, Centre Hospitalier Universitaire de Québec, Québec, Canada

Review of plastic and liquid scintillation dosimetry for photon, electron, and proton therapy

9. Advanced Dosimetry, kV Photon, MeV Electron, MV Photon, Proton (and other Particules), Fundamental Research Show more

While scintillation dosimetry has been around for decades, the need for a dosimeter tailored to the reality of modern radiation therapy-in particular a real-time, water-equivalent, energy-independent dosimeter with high spatial resolution-has generated renewed interest in scintillators over the last 10 years. This topical review is intended to provide the medical physics community with a wide overview of scintillation physics, related optical concepts, and applications of plastic scintillation dosimetry.

PHYSICS IN MEDICINE & BIOLOGY
L Beaulieu (1,2), S Beddar (3,4) | 1- Département de physique, génie physique et optique, et Centre de recherche sur le cancer, Université Laval, Québec, CA , 2- Département de radio-oncologie et Axe Oncologie du CRCHU de Québec, QC, CA, 3- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA, 4- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX, USA

Water-equivalent plastic scintillation detectors for high-energy beam dosimetry: II. Properties and measurements

7. Commissioning, 9. Advanced Dosimetry, MeV Electron, MV Photon, Advanced Optical Dosimetry, Fundamental Research Show more

The properties of a new scintillation detector system for use in dosimetry of high-energy beams in radiotherapy have been measured. The most important properties of these detectors are their hgh spatial resolution and their nearly water-equivalence.

PHYSICS IN MEDICINE & BIOLOGY
A.S. Beddar, T.R. Mackie, F.H. Attix | Depanment of Medical Physics, University of Wisconsin Medical School, Madison, Wl, USA

Water-equivalent plastic scintillation detectors for high-energy beam dosimetry: I. Physical characteristics and theoretical consideration

7. Commissioning, 9. Advanced Dosimetry, MeV Electron, MV Photon, Advanced Optical Dosimetry, Fundamental Research Show more

A minimally perturbing plastic scintillation detector has been developed for the dosimetry of high-energy beams in radiotherapy. The detector system consists of two identical parallel sets of radiation-resistant optical fibre bundles, each connected to independent photomultiplier tubes.

PHYSICS IN MEDICINE & BIOLOGY
A.S. Beddar, T.R. Mackie, F.H. Attix | Depanment of Medical Physics, University of Wisconsin Medical School, Madison, Wl, USA

A method to correct for temperature dependence and measure simultaneously dose and temperature using a plastic scintillation detector

5. In Vivo Dosimetry, 9. Advanced Dosimetry, MeV Electron, MV Photon, Fundamental Research Show more

Plastic scintillation detectors work well for radiation dosimetry. However, they show some temperature dependence, and a priori knowledge of the temperature surrounding the plastic scintillation detectors is required to correct for this dependence.

PHYSICS IN MEDICINE & BIOLOGY
F.Therriault-Proulx, L.Wooton, S.Beddar | Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA

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

4. FLASH-RT / UHDR, 7. Commissioning, MeV Electron, Commissioning, Detector comparaison, Quality Assurance Show more

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

Quantifying the DNA-damaging Effects of FLASH Irradiation With Plasmid DNA

4. FLASH-RT / UHDR, MeV Electron, Rabiobiology Show more

The objective is to investigate a plasmid DNA nicking assay approach for isolating and quantifying the DNA-damaging effects of ultrahigh-dose-rate (ie FLASH) irradiation relative to conventional dose-rate irradiation. The doses and dose rates were verified independently using EBT-XD Gafchromic film placed directly above the DNA-based phantom and HYPERSCINT high temporal resolution plastic scintillator placed immediately beside the DNA phantoms (both phantoms had been previously calibrated at conventional dose rates and validated at FLASH-RT dose rates).

INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY, BIOLOGY, PHYSICS
A.Perstin (1), Y.Poirier (2), A.Sawant (2), M.Tambasco (1) | 1- Department of Physics, San Diego State University, CA, USA, 2- Department of Radiation Oncology, University of Maryland School of Medicine, Maryland, USA