New silicon microdosimetry probes for RBE and biological dose studies using stationary and movable targets in 12C ion therapy

Micro-Mini & Nano-Dosimetry & Innovative Technologies in Radiation Therapy

Chartier, L.^1 ; Tran, L.T.^1 ; Bolst, D.^1 ; Pogossov, A.^1 ; Guatelli, S.^1 ; Petasecca, M.^1 ; Lerch, M.^1 ; Prokopovich, D.^1,2 ; Reinhard, M.^2 ; Perevertaylo, V.^3 ; Jackson, M.^4 ; Matsufuji, N.^5 ; Rosenfeld, A.B.^1

Centre for Medical Radiation Physics, University of Wollongong, Wollongong, Australia^1

Institute of Materials Engineering, Australian Nuclear Science and Technology Organization, Lucas Heights, Australia^2

SBA-BIT, Kiev, Ukraine^3

University of New South Wales, Sydney, Australia^4

Research Centre for Charged Particle Therapy, National Institute of Radiological Sciences, Japan^5

关键词: Biological dose;    Carbon ion therapy;    Clinical environments;    Micro-dosimetry;    Moving targets;    Sensitive volume;    Spread out Bragg peaks;    Treatment planning;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/777/1/012019/pdf
DOI  :  10.1088/1742-6596/777/1/012019

来源: IOP

【 摘 要 】

Due to the high LET and dense ionisation tracks associated with ions, microdosimetric approaches have been used in carbon ion therapy to assess field quality and calculate radiobiological quantities for a variety of cell lines. There is however a lack of instrumentation for simple and routine use in a clinical environment, important for determination of RBE which provides accurate treatment planning and delivery in hadron therapy. In this study, a 10 μm thick silicon microdosimeter with 3D sensitive volumes has been used to investigate the effect of motion on the RBE and field quality of a typical12C ion therapy beam. For a passively scattered 290 MeV/u12C beam with 6 cm spread-out Bragg peak (SOBP), variations in biological dose along the SOBP were observed, as well as a significant changes to particle LET when incident on a moving target.