Published October 2022 | Version v1
Journal article

Experimental verification of ultra high dose rate irradiation effect

  • 1. National Institutes for Quantum Science and Technology, Quantum Medical Science Directorate, National Institute of Radiological Sciences, Chiba (Japan)

Description

The radiotherapy performed at ultra-high dose rate over 40 Gy/s, so called FLASH radiotherapy, has attracted great interests due to its therapeutic advantage. The killing effect to tumors is maintained while the damage to surrounding normal tissues is minimized as compared to the conventional dose rate of < 0.1 Gy/s. The specific point is that the ultra high dose rate irradiation spares healthy tissues. The FLASH effect has been actively investigated in radiobiological studies with electrons, protons and heavy ions. One of key points for the mechanism is in the chemical reactions occurred in tissues. The sparing effect is related to yields of water radiolysis products, which contributes to the indirect action onto the DNA strand break. In this review, we introduce our experimental verification of ultra high dose rate irradiation effect in water by proton and carbon ion irradiation. (author)

Availability note (English)

Available from https://radiation-chemistry.org/kaishi/114pdf/114_39.pdf

Abstract (Japanese)

通常の放射線治療線量率よりも1000倍以上も高い線量率で行われる超高線量率放射線がん治療(FLASH)は治療効果を維持しつつ,正常組織への副作用を低減できることから大きな注目を浴びている.そのメカニズムとして間接作用を低減する効果との見方があり,短時間での高線量照射による水の放射線分解生成物と酸素との反応や密なトラック構造の重なり合いによるラジカル再結合の可能性が指摘されている.本研究では,超高線量率照射効果を実験的に検証するために,陽子・炭素線照射による水の放射線分解生成物の収率の線量率依存性を調べている.本稿では現在取り組んでいる放射線化学実験で得られた結果・考察について紹介する.(著者)

Additional details

Additional titles

Original title (Japanese)
超高線量率照射効果のメカニズム解明に向けた取り組み

Publishing Information

Journal Title
Hoshasen Kagaku (Online)
Journal Issue
no.114
Series
雑誌名:放射線化学
Journal Page Range
p. 39-43
ISSN
2188-0115

Optional Information

Notes
25 refs., 5 figs.