Development of a three-dimensional gel dosimeter for heavy particle scanning irradiation and its clinical application

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K07696
• 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: Yokohama National University
• Principal Investigator: Gotoh Hiroaki 横浜国立大学, 大学院工学研究院, 准教授 (80635235)
• Co-Investigator(Kenkyū-buntansha): 草野 陽介 地方独立行政法人神奈川県立病院機構神奈川県立がんセンター(臨床研究所), その他部局等, その他 (40619665) ; 蓑原 伸一 地方独立行政法人神奈川県立病院機構神奈川県立がんセンター(臨床研究所), その他部局等, その他 (60239332)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 放射線計測 / 重粒子線治療 / ゲル線量計 / 三次元線量分布 / 線量評価

Outline of Final Research Achievements

In this study, basic tests were carried out on the applicability of the developed color-gel dosimeter to the measurement of absorbed dose distribution during heavy particle irradiation. The discrepancy (accuracy) between the absorbed dose and the absolute value of the gel dosimeter measurements, which is a problem to be solved, was also examined. Furthermore, moving targets and real-time measurements were also examined. As a result, a correction method using OH radical concentration was developed, which corrects for the colouration of the color-gel dosimeter and allows the error to be evaluated in comparison with the relative value of the absorbed dose expected in the treatment plan. The results were also applied to the observation of changes over time during SOBP irradiation and the analysis of absorbed doses for irradiation of moving targets.

Free Research Field

物理有機化学

Academic Significance and Societal Importance of the Research Achievements

重粒子線高速3次元スキャニング照射は、その高性能さゆえにより精密な線量分布の計測が求められているが、複雑な分布を高速に一度の照射で正確に3次元で再現できる線量計が存在しない。本研究では、重粒子線高速3次元スキャニング照射を可視化できる３次元ゲル線量計の開発に向けた基礎的な研究を行った。