Precise Pulse Delivery Control Using Monitor Units in Electron FLASH-RT

4. FLASH-RT / UHDR, MeV Electron, LINAC Pulse Discrimination, Real-time Dosimetry Show more

In electron FLASH-RT, precise delivery of the correct number of pulses is critical to accurate dose administration in preclinical radiobiological studies. This work investigates the use of LINAC monitor ion chambers to most precisely control FLASH pulse delivery. Calibrated plastic scintillation detector and EBT-XD Gafchromic films were used for online and passive dosimetry, respectively. The plastic scintillation detector also served as a direct pulse counter.

2021 AAPM ANNUAL MEETING
J.Xu, Y.Poirier, A.Sawant | University of Maryland School of Medicine, MD, USA

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

FLASH Irradiation of Drosophila Melanogaster Using Low Energy X-Rays

4. FLASH-RT / UHDR, 5. In Vivo Dosimetry, kV Photon, Rabiobiology Show more

To investigate the capability of low energy x-rays to elicit the FLASH effect, Drosophila melanogaster larvae were irradiated with ultrahigh dose-rate and conventional radiotherapy dose rates using an inexpensive x-ray tube system. Dosimetry was performed with plastic scintillators and radiochromic film, and the differential survival observed in this work suggests that continuous 120 kVp x-rays can induce a FLASH effect.

2022 AAPM ANNUAL MEETING
A.Hart, J.Dudzic, J.Eby, S.Perlman, M.Bazalova-Carter | University of Victoria, Victoria, BC ,CA

Dosimetric Characterization of the ARIEL 10 MV X-Ray Ultrahigh Dose-Rate (FLASH) Irradiation Platform at TRIUMF

4. FLASH-RT / UHDR, 9. Advanced Dosimetry, MV Photon, Detector comparaison, Fundamental Research Show more

The purpose was to characterize the beam delivery capabilities and dose rates achievable on the new ultrahigh dose-rate 10MV x-ray irradiation platform at TRIUMF. Beam commissioning and dosimetry have been conducted on the ARIEL x-ray FLASH irradiation platform using film doses and scintillators. Measured dose rates support that the 10MV x-ray beam may be used as a UHDR source compatible with FLASH radiobiological experiments.

2022 AAPM ANNUAL MEETING
N.Esplen (1), L.Egoriti (2), T.Planche (3), A.Hart (1), B.Paley (3), C.Hoehr (3), A.Gottberg (3), M.Bazalova-Carter (1) | 1- University of Victoria, BC ,CA, 2- University of British Columbia, BC, CA, 3- TRIUMF, BC, CA

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

Characterization of an x‐ray tube‐based ultrahigh dose‐rate system for in vitro irradiations.

4. FLASH-RT / UHDR, kV Photon, Rabiobiology, Real-time Dosimetry Show more

To present an x-ray tube system capable of in vitro ultrahigh dose-rate (UHDR) irradiation of small < 0.3 mm samples and to characterize it by means of a plastic scintillation detector (PSD).

Med Phys. 2021
D.Cecchi (1), F.Therriault-Proulx (2), S.Lambert-girard (2), A.Hart (1), A.Macdonald (1), M.Pfleger (1), M.Lenckowski (1), M.Bazalova-Carter (1) | Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia, Canada, MedScint, QC, CA

Feasibility of Plastic Scintillator Dosimeters for FLASH Therapy

4. FLASH-RT / UHDR, MeV Electron, Advanced Optical Dosimetry Show more

To examine the capabilities of plastic scintillator dosimeters (PSDs) to accurately measure FLASH radiotherapy dose rates delivered with an x-ray tube.

2020 AAPM AM
D.Cecchi (1), F.Therriault-Proulx (2), M.Bazalova-Carter (1) | University of Victoria, Victoria, BC ,CA,, Medscint, QC, CA