2014年
Influence of difference in cross-sectional dose profile in a CTDI phantom on X-ray CT dose estimation: A Monte Carlo study
Radiological Physics and Technology
- ,
- ,
- 巻
- 7
- 号
- 1
- 開始ページ
- 133
- 終了ページ
- 140
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1007/s12194-013-0242-1
- 出版者・発行元
- Springer-Verlag Tokyo
The longitudinal dose profile in a computed tomography dose index (CTDI) phantom had been studied by many researchers. The cross-sectional dose profile in the CTDI phantom, however, has not been studied. It is also important to understand the cross-sectional dose profile in the CTDI phantom for dose estimation in X-ray CT. In this study, the cross-sectional dose profile in the CTDI phantom was calculated by use of a Monte Carlo (MC) simulation method. A helical or a 320-detector-row cone-beam X-ray CT scanner was simulated. The cross-sectional dose profile in the CTDI phantom from surface to surface through the center point was calculated by MC simulation. The shape of the calculation region was a cylinder of 1-mm-diameter. The length of the cylinder was 23, 100, or 300 mm to represent various CT ionization chamber lengths. Detailed analyses of the energy depositions demonstrated that the cross-sectional dose profile was different in measurement methods and phantom sizes. In this study, we also focused on the validation of the weighting factor used in weighted CTDI (CTDIw). As it stands now, the weighting factor used in CTDI w is (1/3, 2/3) for the (central, peripheral) axes. Our results showed that an equal weighting factor, which is (1/2, 1/2) for the (central, peripheral) axes, is more suitable to estimate the average cross-sectional dose when X-ray CT dose estimation is performed. © Japanese Society of Radiological Technology and Japan Society of Medical Physics 2013.
- リンク情報
- ID情報
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- DOI : 10.1007/s12194-013-0242-1
- ISSN : 1865-0341
- ISSN : 1865-0333
- PubMed ID : 24272457
- SCOPUS ID : 84896057866