ArticleInternational journal of radiation oncology, biology, physics2021
Quantification of Oxygen Depletion During FLASH Irradiation In Vitro and In Vivo.
Article in International journal of radiation oncology, biology, physics, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 127 papers, 3 of them syntheses that pooled it.
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Who cites it
127 citing papers in PubMed, 3 syntheses or guidelines pooled it.
- Global clinical landscape and multidisciplinary translational frontiers of FLASH radiotherapy: a systematic review and visualized bibliometric mapping based on WoSCC and PubMed (2014-2025).Frontiers in medicine · 2026Pooled it
- The current status of FLASH particle therapy: a systematic review.Physical and engineering sciences in medicine · 2023Pooled it
- Examining the Occurrence of the FLASH Effect in Animal Models: A Systematic Review and Meta-Analysis of Ultra-High Dose Rate Proton or Carbon Ion Irradiation.Technology in cancer research & treatmentPooled it
- X‑ray FLASH RT inhibits lung cancer bone metastasis via activating CD4⁺ T-cell‑mediated antitumor immunity with modulation of Th17 cell response.Oncoimmunology · 2026Article
- Physicochemical modeling of electron FLASH to identify the roles of oxygen, aqueous electrons and causal radical recombination effects underlying them.Physics in medicine and biology · 2026Article
- Geant4-DNA Simulation of the Oxygen Depletion Coefficient and the Relative Change in OER in Proton-Irradiated Oxygenated Water.International journal of molecular sciences · 2026Article
- Harnessing Particle Ions for FLASH Radiotherapy.Cells · 2026Review
- Oxygels: Tunable Phosphorescent Hydrogels for Cherenkov-Excited Luminescence Imaging (CELI) of Oxygen.Advanced healthcare materials · 2026Article
- FLASH radiotherapy: physico-chemical considerations on ionisation tracks, radical reactions, and the role of oxygen.Radiation oncology (London, England) · 2026Review
- TOPAS-nBio simulation of the impact of ultrahigh dose rate and oxygen concentration on the Fenton reaction using the Fricke solution.Medical physics · 2026Article
- Harnessing the sparing effect of FLASH-RT: From phenomenon observation, radiophysical determinants to molecular mechanisms and synergistic strategies.Materials today. Bio · 2026Review
- Article
- Radiation-Induced Modifications in Bovine Serum Albumin in Saline Solutions Under E-Beam Irradiation.International journal of molecular sciences · 2026Article
- Article
- Proton FLASH Exposure Preserves Gut Commensal Microbiomes and Spares Intestinal Stem Cells.Advanced science (Weinheim, Baden-Wurttemberg, Germany) · 2026Article
- A new perspective on radiotherapy in the comprehensive treatment of cancer.Precision radiation oncology · 2026Review
- Systematic tissue oxygen variation shows the modulation of murine skin radiation toxicity at ultra-high dose rates.Physics in medicine and biology · 2026Article
- A modified lethal-potentially lethal model for oxygen-mediated FLASH sparing in stem cell niches.Medical physics · 2026Article
- Kinetic model of radiochemical oxygen depletion (ROD) in FLASH radiotherapy.Medical physics · 2026Article
- Oxygen Depletion in FLASH Particle Therapy: Effects of Linear Energy Transfer and Ion Track Structure.Antioxidants (Basel, Switzerland) · 2026Article
67 more citing papers are in PubMed but not listed here.
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Authors and funding
14 authors.
Funding
Abstract
purposeDelivery of radiation at ultrahigh dose rates (UHDRs), known as FLASH, has recently been shown to preferentially spare normal tissues from radiation damage compared with tumor tissues. However, the underlying mechanism of this phenomenon remains unknown, with one of the most widely considered hypotheses being that the effect is related to substantial oxygen depletion upon FLASH, thereby altering the radiochemical damage during irradiation, leading to different radiation responses of normal and tumor cells. Testing of this hypothesis would be advanced by direct measurement of tissue oxygen in vivo during and after FLASH irradiation. METHODS AND MATERIALS: Oxygen measurements were performed in vitro and in vivo using the phosphorescence quenching method and a water-soluble molecular probe Oxyphor 2P. The changes in oxygen per unit dose (G-values) were quantified in response to irradiation by 10 MeV electron beam at either UHDR reaching 300 Gy/s or conventional radiation therapy dose rates of 0.1 Gy/s.
resultsIn vitro experiments with 5% bovine serum albumin solutions at 23°C resulted in G-values for oxygen consumption of 0.19 to 0.21 mm Hg/Gy (0.34-0.37 μM/Gy) for conventional irradiation and 0.16 to 0.17 mm Hg/Gy (0.28-0.30 μM/Gy) for UHDR irradiation. In vivo, the total decrease in oxygen after a single fraction of 20 Gy FLASH irradiation was 2.3 ± 0.3 mm Hg in normal tissue and 1.0 ± 0.2 mm Hg in tumor tissue (P < .00001), whereas no decrease in oxygen was observed from a single fraction of 20 Gy applied in conventional mode.
conclusionsOur observations suggest that oxygen depletion to radiologically relevant levels of hypoxia is unlikely to occur in bulk tissue under FLASH irradiation. For the same dose, FLASH irradiation induces less oxygen consumption than conventional irradiation in vitro, which may be related to the FLASH sparing effect. However, the difference in oxygen depletion between FLASH and conventional irradiation could not be quantified in vivo because measurements of oxygen depletion under conventional irradiation are hampered by resupply of oxygen from the blood.
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