Dose-rate scaling factor estimation of THOR BNCT test beam.
In 1998, an epithermal neutron test beam was designed and constructed at the Tsing Hua Open-Pool Reactor (THOR) for the purpose of preliminary dosimetric experiments in boron neutron capture therapy (BNCT). A new epithermal neutron beam was designed at this facility, and is currently under construction, with clinical trials targeted in late 2004. Depth dose-rate distributions for the THOR BNCT test beam have been measured by means of activation foil and dual ion chamber techniques. Neutron and structure-induced gamma spectra measured at the test beam exit were configured into a source function for the Monte Carlo-based treatment planning code NCTPlan. Dose-rate scaling factors (DRSFs) were determined to normalize computationally derived dose-rate distributions with experimental measurements in corresponding mathematical and physical phantoms, and to thus enable accurate treatment planning using the NCTPlan code. A similar approach will be implemented in characterizing the new THOR epithermal beam in preparation for clinical studies. This paper reports the in-phantom calculated and experimental dosimetry comparisons and derived DRSFs obtained with the THOR test beam.
Hsu
F Y
FY
Yuanpei University of Science and Technology, 306 Yuanpei Street, Hsinchu 300, Taiwan. fyhsu@mail.yust.edu.tw
Tung
C J
CJ
Chen
J C
JC
Wang
Y L
YL
Huang
H C
HC
Zamenhof
R G
RG
D016754:Boron Neutron Capture Therapy / Q000295:instrumentation* / Q000706:statistics & numerical data*; D001932:Brain Neoplasms / Q000532:radiotherapy; D006801:Humans; D009010:Monte Carlo Method; D019047:Phantoms, Imaging; D011874:Radiometry / Q000295:instrumentation; D011880:Radiotherapy Planning, Computer-Assisted / Q000706:statistics & numerical data; D013624:Taiwan