TY - JOUR
T1 - Estimation of the optical errors on the luminescence imaging of water for proton beam
AU - Yabe, Takuya
AU - Komori, Masataka
AU - Horita, Ryo
AU - Toshito, Toshiyuki
AU - Yamamoto, Seiichi
N1 - Funding Information:
The proton-beam measurements were performed at the Nagoya Proton Therapy Center. We thank the clinical teams for allowing us beam times for our experiments as well as its staff members who helped us prepare and carry out the irradiations. This work was supported in part by JSPS KAKENHI Grant Number JP25253077 , JP16H03908 and JP16K15349 .
Funding Information:
The proton-beam measurements were performed at the Nagoya Proton Therapy Center. We thank the clinical teams for allowing us beam times for our experiments as well as its staff members who helped us prepare and carry out the irradiations. This work was supported in part by JSPS KAKENHI Grant Number JP25253077, JP16H03908 and JP16K15349.
Publisher Copyright:
© 2018 Elsevier B.V.
PY - 2018/4/21
Y1 - 2018/4/21
N2 - Although luminescence imaging of water during proton-beam irradiation can be applied to range estimation, the height of the Bragg peak of the luminescence image was smaller than that measured with an ionization chamber. We hypothesized that the reasons of the difference were attributed to the optical phenomena; parallax errors of the optical system and the reflection of the luminescence from the water phantom. We estimated the errors cause by these optical phenomena affecting the luminescence image of water. To estimate the parallax error on the luminescence images, we measured the luminescence images during proton-beam irradiation using a cooled charge-coupled camera by changing the heights of the optical axis of the camera from those of the Bragg peak. When the heights of the optical axis matched to the depths of the Bragg peak, the Bragg peak heights in the depth profiles were the highest. The reflection of the luminescence of water with a black wall phantom was slightly smaller than that with a transparent phantom and changed the shapes of the depth profiles. We conclude that the parallax error significantly affects the heights of the Bragg peak and the reflection of the phantom affects the shapes of depth profiles of the luminescence images of water.
AB - Although luminescence imaging of water during proton-beam irradiation can be applied to range estimation, the height of the Bragg peak of the luminescence image was smaller than that measured with an ionization chamber. We hypothesized that the reasons of the difference were attributed to the optical phenomena; parallax errors of the optical system and the reflection of the luminescence from the water phantom. We estimated the errors cause by these optical phenomena affecting the luminescence image of water. To estimate the parallax error on the luminescence images, we measured the luminescence images during proton-beam irradiation using a cooled charge-coupled camera by changing the heights of the optical axis of the camera from those of the Bragg peak. When the heights of the optical axis matched to the depths of the Bragg peak, the Bragg peak heights in the depth profiles were the highest. The reflection of the luminescence of water with a black wall phantom was slightly smaller than that with a transparent phantom and changed the shapes of the depth profiles. We conclude that the parallax error significantly affects the heights of the Bragg peak and the reflection of the phantom affects the shapes of depth profiles of the luminescence images of water.
KW - Dose estimation
KW - Imaging
KW - Luminescence
KW - Optical error
KW - Proton beam
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U2 - 10.1016/j.nima.2018.01.030
DO - 10.1016/j.nima.2018.01.030
M3 - Article
AN - SCOPUS:85041472264
SN - 0168-9002
VL - 888
SP - 163
EP - 168
JO - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
JF - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
ER -