A development of small spectrometer for clinical use

• Project/Area Number: 23791451
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Radiation science
• Research Institution: Teikyo University
• Principal Investigator: KOTOKU Junichi 帝京大学, 医療技術学部, 講師 (70450195)
• Co-Investigator(Renkei-kenkyūsha): KOBAYASHI Takenori 帝京大学, 医療技術学部, 教授 (10459365)
• Project Period (FY): 2011 – 2012
• Project Status: Completed (Fiscal Year 2012)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2012: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2011: ¥3,250,000 (Direct Cost: ¥2,500,000、Indirect Cost: ¥750,000)
• Keywords: 逆問題 / エネルギースペクトル推定 / PDD / リニアック / エネルギースペクトル / スペクトロスコピー

Research Abstract

The energy spectrum of a clinical photon beam constitutes the most upstream information and is critical in dose distribution. However, the technical difficulty of photon counting has hampered attempts to determine this energy spectrum. In this paper , we present a scheme that infers the X-ray energy spectrum of a linear particle accelerator on the basis of the percentage depth dose (PDD) in an ion chamber.We assumed a linear relationship between the clinical photon beam spectrum and the PDD of the beam. The photon spectrum was then estimated as a solution of maximum a posteriori. The PDD of 4-MV X-rays was measured using an ion chamber and a three-dimensional water phantom in Teikyo University Hospital.Our inference method proved to be effective and powerful in estimating the X-ray energy spectrum. The estimated spectrum closely matched the spectrum modeled in the commercial treatment planning system. Although our method is tested only on a single case, the method is validated by its successful output.

Research Products

• [Journal Article] Energy Spectrum Inference of X‐Rays from a Linac (2012)
  • Author(s): Jun'ichi Kotoku, Shinobu Kumagai, Norikazu Arai, Naoya Saotom, Akihiro Haga and Takenori Kobayashi
  • Journal Title: Medical Physics Volume: 39 Pages: 3715-3715
  • URL: http://dx.doi.org/10.1118/1.4735112
  • Peer Reviewed
• [Journal Article] The improvement of discrepancy between radiotherapy treatment planning system and verificationsystem using Effective Density Method (2012)
  • Author(s): Shinobu Kumagai, M. Okajima, H. Takaya, N. Arai, K. Waga, T. Tanaka, M. Yasuda, K. Takimoto, J. Kotoku and T Kobayashi
  • Journal Title: KEK Proceedings 2012-7 Volume: 1 Pages: 66-75
• [Journal Article] The improvement of discrepancy between radiotherapy treatment planning system and verification system using Effective Density Method (2012)
  • Author(s): Shinobu Kumagai
  • Journal Title: KEK Proceedings 2012-7 Volume: 1 Pages: 66-75
• [Journal Article] Dose Calculation of KV Cone‐Beam CT by Use of Pinnacle (2011)
  • Author(s): J Kotoku, A Haga, S Saegusa, N Arai, T Kobayashi, K Waga, A Sakumi, S Itoh, S Kida, N Saotome, K Nakagawa, H Kanemitsu, and K Ishioka
  • Journal Title: Medical Physics Volume: 38 Pages: 3723-3723
  • URL: http://dx.doi.org/10.1118/1.3613006
  • Peer Reviewed
• [Journal Article] Dose Calculation of KV Cone‐Beam CT by Use of Pinnacle (2011)
  • Author(s): Jun'ichi Kotoku
  • Journal Title: Medical Physics Volume: 38 Pages: 3723-3723
  • Peer Reviewed
• [Presentation] Energy Spectrum Inference of clinical photon beam by use of PDD (2013)
  • Author(s): Jun'ichi Kotoku, Shinobu Kumagai, Norikazu Arai, Naoya, Akihiro Haga, Takenori Kobayashi
  • Organizer: 55th AAPM Annual Meeting & Exhibition
  • Place of Presentation: Indianapolis, USA
  • Year and Date: 2013-08-05
• [Presentation] Energy Spectrum Inference of clinical photon beam by use of PDD (2013)
  • Author(s): 古徳純一、熊谷仁、新井範一、早乙女直也 、芳 賀 昭 弘 、小 林 毅 範
  • Organizer: 第105回日本医学物理学会
  • Place of Presentation: パシフィコ横浜
  • Year and Date: 2013-04-12
• [Presentation] X 線治療における物理学 (2013)
  • Author(s): 古徳純一
  • Organizer: 日本物理学会第68回年次大会シンポジウム医学における物理学の貢献
  • Place of Presentation: 広島大学
  • Year and Date: 2013-03-28
• [Presentation] 3D ゲル線量計で推定する リニアックのエネルギースペクトル (2012)
  • Author(s): 古徳純一、熊谷仁、新井範一、早乙女直也、芳賀昭弘、小林毅範
  • Organizer: 第1回 3 次元(3D)ゲル線量計研究会
  • Place of Presentation: 広島大学
  • Year and Date: 2012-12-02
• [Presentation] リニアックの 頑健なエネルギースペクトル推定 (2012)
  • Author(s): 古徳純一、熊谷仁、新井範一、芳賀昭弘、小林毅範
  • Organizer: 第104回日本医学物理学会
  • Place of Presentation: パシフィコ横浜
  • Year and Date: 2012-09-15
• [Presentation] リニアックのエネルギースペクトル推定 (2012)
  • Author(s): 古徳純一、熊谷仁、新井範一、芳賀昭弘、小林毅範
  • Organizer: 第103回日本医学物理学会
  • Place of Presentation: パシフィコ横浜
  • Year and Date: 2012-04-12
• [Presentation] Dose Calculation of KV Cone‐Beam CT by Use of Pinnacle (2011)
  • Author(s): Jun'ichi Kotoku
  • Organizer: AAPM Anual Meeting
  • Place of Presentation: バンクーバー
• [Presentation] リニアックのエネルギースペクトル推定
  • Author(s): 古徳純一
  • Organizer: 第103回日本医学物理学会
  • Place of Presentation: パシフィコ横浜
• [Presentation] リニアックの 頑健なエネルギースペクトル推定
  • Author(s): 古徳純一
  • Organizer: 第104回日本医学物理学会
  • Place of Presentation: パシフィコ横浜
• [Presentation] 3Dゲル線量計で推定する リニアックのエネルギースペクトル
  • Author(s): 古徳純一
  • Organizer: 第1回 3次元(3D)ゲル線量計研究会
  • Place of Presentation: 広島大学
• [Presentation] X線治療における物理学
  • Author(s): 古徳純一
  • Organizer: 日本物理学会第68回年次大会シンポジウム医学における物理学の貢献
  • Place of Presentation: 広島大学
  • Invited
• [Presentation] Energy Spectrum Inference of clinical photon beam by use of PDD
  • Author(s): 古徳純一
  • Organizer: 第105回日本医学物理学会
  • Place of Presentation: パシフィコ横浜
• [Presentation] Energy Spectrum Inference of clinical photon beam by use of PDD
  • Author(s): Jun'ichi Kotoku
  • Organizer: 55th AAPM Annual Meeting & Exhibition
  • Place of Presentation: Indianapolis, USA
• [Remarks]
  • URL: http://www.e-campus.gr.jp/staffinfo/public/staff/detail/1339/35