Imaging Cherenkov emission for quality assurance of radiation therapy

• Project/Area Number: 18K07679
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 52040:Radiological sciences-related
• Research Institution: Nagoya University
• Principal Investigator: Yogo Katsunori 名古屋大学, 医学系研究科(保健), 助教 (30424823)
• Co-Investigator(Kenkyū-buntansha): 前山 拓哉 北里大学, 理学部, 助教 (70612125)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2020: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2019: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2018: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• Keywords: 放射線治療 / チェレンコフ光 / 高線量率小線源治療 / 品質保証 / 線源位置測定 / 品質保証(QA) / 192Ir γ線 / 品質管理 / 水の発光 / γ線 / 医学物理 / 放射線化学 / 放射線生物

Outline of Final Research Achievements

We developed a novel and simple method to measure the source positions in applicators directly for high-dose-rate (HDR) brachytherapy based on Cherenkov emission imaging, and evaluated the performance. The light emission from plastic applicators, irradiated by an 192Ir γ-ray source, was captured using a charge-coupled device camera. We attached plastics to a metal applicator, to use as screens for the Cherenkov imaging.
We determined the source positions and dwell intervals from the light profiles and compared these with preset values and dummy marker measurements. The source positions and dwell intervals measured from the light images were comparable to the dummy marker measurements and preset values. The proposed method should be suitable for rapid and easy quality assurance (QA) investigations in HDR brachytherapy. The method allows for real-time, filmless measurements of the source positions to be obtained and is useful for rapid feedback in QA procedures.

Academic Significance and Societal Importance of the Research Achievements

高線量率小線源治療の品質保証は、従来、時間がかかり、煩雑であったが、この方法により、迅速かつ簡便に行うことが可能になった。線源動作エラーを未然に発見することで、さらに、安全ながん放射線治療に寄与すると期待される。放射線による治療器具の発光を、広くがん放射線治療の品質保証法に適用できる可能性を示すことができるため、さらなる応用が期待される。

Research Products

• [Journal Article] Source position measurement by Cherenkov emission imaging from applicators for high-dose-rate brachytherapy (2021)
  • Author(s): K Yogo, Y Noguchi, K Okudaira, M Nozawa, H Ishiyama, H Yasuda, H Okamoto, H Oguchi, S Yamamoto
  • Journal Title: Medical Physics Volume: 48 Issue: 1 Pages: 488-499
  • DOI: 10.1002/mp.14606
  • Peer Reviewed
• [Journal Article] Effect of gold nanoparticle radiosensitization on plasmid DNA damage induced by high-dose rate brachyth erap (2021)
  • Author(s): Yogo K, Misawa M, Shimizu M, Shimizu H, Kitagawa T, Hirayama R, Ishiyama H, Furukawa T, Yasuda H.
  • Journal Title: Int J Nanomedicine Volume: 14;16 Pages: 359-370
  • DOI: 10.2147/ijn.s292105
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Imaging Cherenkov emission for quality assurance of high-dose-rate brachytherapy (2020)
  • Author(s): K Yogo, A Matsushita, Y Tatsuno, T Shimo, S Hirota, M Nozawa, S Ozawa, H Ishiyama, H Yasuda, Y Nagata & K Hayakawa
  • Journal Title: Scientific Reports Volume: 10 Issue: 1 Pages: 3572-3572
  • DOI: 10.1038/s41598-020-60519-z
  • Peer Reviewed / Open Access
• [Journal Article] Scintillator screen for measuring low-dose halo in scanning carbon-ion therapy (2020)
  • Author(s): K Yogo, Y Tatsuno, H Souda, A Matsumura, M Tsuneda, Y Hirano, H Ishiyama, A Saito, S Ozawa, Y Nagata, T Nakano, K Hayakawa, and T Kanai
  • Journal Title: Radiation Measurements Volume: 133 Pages: 106299-106299
  • DOI: 10.1016/j.radmeas.2020.106299
  • Peer Reviewed
• [Journal Article] Scintillator screen for measuring dose distribution in scanned carbon-ion therapy (2019)
  • Author(s): K Yogo, Y Tatsuno, H Souda, A Matsumura, M Tsuneda, Y Hirano, H Ishiyama, A Saito, S Ozawa, Y Nagata, T Nakano, K Hayakawa, T Kanai
  • Journal Title: Radiation Measurements Volume: 129 Pages: 106207-106207
  • DOI: 10.1016/j.radmeas.2019.106207
  • Peer Reviewed
• [Presentation] Source position measurement by Cherenkov emission imaging from applicators for high-dose-rate brachytherapy (2021)
  • Author(s): 余語克紀，野口由美子, 奥平訓康, 野澤茉莉花, 石山博條, 岡本裕之, 保田浩志, 小口宏, 山本誠一
  • Organizer: 日本医学物理学会
• [Presentation] Imaging Cherenkov emission for quality assurance of high-dose-rate brachytherapy (2020)
  • Author(s): 余語克紀，下貴裕, 廣田 誠子, 野澤茉莉花, 石山博條, 保田浩志
  • Organizer: 日本医学物理学会
• [Presentation] チェレンコフ光の可視化による高線量率小線源治療の品質保証ツールの開発 (2019)
  • Author(s): 余語克紀，下貴裕, 廣田 誠子, 保田浩志, 野澤茉莉花, 石山博條
  • Organizer: 第8回3Dゲル研究会
• [Presentation] Output characteristics of Cerenkov emission for a quality assurance tool in HDR brachytherapy (2018)
  • Author(s): 余語克紀
  • Organizer: 日本医学物理学会