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Dose profile measurement of a four-dimensional CT (4D-CT)
https://repo.qst.go.jp/records/67716
https://repo.qst.go.jp/records/6771696258577-f949-4f46-8d68-829433419e4d
| Item type | 会議発表用資料 / Presentation(1) | |||||
|---|---|---|---|---|---|---|
| 公開日 | 2004-02-20 | |||||
| タイトル | ||||||
| タイトル | Dose profile measurement of a four-dimensional CT (4D-CT) | |||||
| 言語 | ||||||
| 言語 | eng | |||||
| 資源タイプ | ||||||
| 資源タイプ識別子 | http://purl.org/coar/resource_type/c_c94f | |||||
| 資源タイプ | conference object | |||||
| アクセス権 | ||||||
| アクセス権 | metadata only access | |||||
| アクセス権URI | http://purl.org/coar/access_right/c_14cb | |||||
| 著者 |
Endo, Masahiro
× Endo, Masahiro× Mori, Shinichirou× Tsunoo, Takanori× Nishizawa, Kanae× Aoyama, Takahiko× 遠藤 真広× 森 慎一郎× 角尾 卓紀× 西澤 かな枝 |
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| 抄録 | ||||||
| 内容記述タイプ | Abstract | |||||
| 内容記述 | [Purpose] We have developed a four-dimensional CT (4D-CT) using continuous rotation of cone-beam x-ray. The maximum field of view for 4D-CT is 128mm at the center of rotation in the longitudinal direction. In order to obtain appropriate estimations of exposure dose, we have measured dose profiles perpendicular to the rotation axis in a lucite cylinder of 320mm diameter. [Methods] We have used cylindrical lucite phantom of 320mm diameter and 750mm length. Dose profiles were measured at the center and a peripheral point of 10mm depth. A pin silicon photodiode sensor with 3x3x3mm sensitive region was used as an x-ray detector, which was scanned along longitudinal direction in the phantom for collimator widths of 10, 32, 64, 96 and 128mm. [Results] The dose profiles had long tails caused by scattered radiation. For 128 mm collimator width 90% of integral dose was distributed along 350mm length at the center and 220mm at the periphery. Even for 10 mm collimator width 90% of integral dose was distributed along 250mm length at the center and 160mm length at the periphery. [New or breakthrough work to be presented] Before the advent of multi-detector CT CTDI100 was a good estimation of exposure dose, because it expressed approximate integral dose for clinical scan conditions. For 4D-CT employing a variable collimator, the standard CTDI was not a good estimation. In the present work we measured dose profiles for 4D-CT, and showed long tails distributed more than 100mm out of the collimator edge. [Conclusion] In order to estimate exposure dose for cone-beam CT such as 4D-CT, it should be recommended to measure integral dose over collimator width plus at least 200mm length. |
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| 会議概要（会議名, 開催地, 会期, 主催者等） | ||||||
| 内容記述タイプ | Other | |||||
| 内容記述 | SPIE medical imaging | |||||
| 発表年月日 | ||||||
| 日付 | 2004-02-19 | |||||
| 日付タイプ | Issued | |||||
