Oxygen Consumption In Vivo by Ultra-High Dose Rate Electron Irradiation Depends Upon Baseline Tissue Oxygenation.

Purpose: This study aimed to assess the impact of tissue oxygen levels on transient oxygen consumption induced by ultra-high dose rate (UHDR) electron radiation in murine flank and to examine the effect of dose rate variations on this relationship.

Methods And Materials: Real-time oximetry using the phosphorescence quenching method and Oxyphor PdG4 molecular probe was employed. Continuous measurements were taken during radiation delivery on a UHDR-capable Mobetron linear accelerator.

Commissioning an ultra-high-dose-rate electron linac with end-to-end tests.

. The FLASH effect can potentially be used to improve the therapeutic ratio of radiotherapy (RT) through delivery of Ultra-high-dose-rate (UHDR) irradiation. Research is actively being conducted to translate UHDR-RT and for this purpose the Mobetron is capable of producing electron beams at both UHDR and conventional dose rates for FLASH research and translation.

Electron beam response corrections for an ultra-high-dose-rate capable diode dosimeter.

Background: Ultra-high-dose-rate (UHDR) electron beams have been commonly utilized in FLASH studies and the translation of FLASH Radiotherapy (RT) to the clinic. The EDGE diode detector has potential use for UHDR dosimetry albeit with a beam energy dependency observed.

Purpose: The purpose is to present the electron beam response for an EDGE detector in dependence on beam energy, to characterize the EDGE detector's response under UHDR conditions, and to validate correction factors derived from the first detailed Monte Carlo model of the EDGE diode against measurements, particularly under UHDR conditions.

Anesthetic Oxygen Use and Sex Are Critical Factors in the FLASH Sparing Effect.

Purpose: Ultra High Dose-Rate (UHDR) radiation has been reported to spare normal tissue, compared with Conventional Dose-Rate (CDR) radiation. However, important work remains to be done to improve the reproducibility of the FLASH effect. A better understanding of the biologic factors that modulate the FLASH effect may shed light on the mechanism of FLASH sparing.

First Monte Carlo beam model for ultra-high dose rate radiotherapy with a compact electron LINAC.

Background: FLASH radiotherapy based on ultra-high dose rate (UHDR) is actively being studied by the radiotherapy community. Dedicated UHDR electron devices are currently a mainstay for FLASH studies.

Purpose: To present the first Monte Carlo (MC) electron beam model for the UHDR capable Mobetron (FLASH-IQ) as a dose calculation and treatment planning platform for preclinical research and FLASH-radiotherapy (RT) clinical trials.

Anesthetic oxygen use and sex are critical factors in the FLASH sparing effect.

Introduction: Ultra-high dose-rate (UHDR) radiation has been reported to spare normal tissue compared to conventional dose-rate (CDR) radiation. However, reproducibility of the FLASH effect remains challenging due to varying dose ranges, radiation beam structure, and in-vivo endpoints. A better understanding of these inconsistencies may shed light on the mechanism of FLASH sparing.

Characterization of a diode dosimeter for UHDR FLASH radiotherapy.

Background: Ultra-high dose rate (UHDR) FLASH beams typically deliver dose at rates of  >40 Gy/sec. Characterization of these beams with respect to dose, mean dose rate, and dose per pulse requires dosimeters which exhibit high temporal resolution and fast readout capabilities.

Purpose: A diode EDGE Detector with a newly designed electrometer has been characterized for use in an UHDR electron beam and demonstrated appropriateness for UHDR FLASH radiotherapy dosimetry.

Color-resolved Cherenkov imaging allows for differential signal detection in blood and melanin content.

Significance: High-energy x-ray delivery from a linear accelerator results in the production of spectrally continuous broadband Cherenkov light inside tissue. In the absence of attenuation, there is a linear relationship between Cherenkov emission and deposited dose; however, scattering and absorption result in the distortion of this linear relationship. As Cherenkov emission exits the absorption by tissue dominates the observed Cherenkov emission spectrum.