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Estimation of scattered radiation amount and its effects on image quality in 4D CT
https://repo.qst.go.jp/records/67680
https://repo.qst.go.jp/records/67680151e228e-c464-44db-ae33-5f3c1b69acb5
| Item type | 会議発表用資料 / Presentation(1) | |||||
|---|---|---|---|---|---|---|
| 公開日 | 2003-12-18 | |||||
| タイトル | ||||||
| タイトル | Estimation of scattered radiation amount and its effects on image quality in 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 |
Mori, Shinichirou
× Mori, Shinichirou× Endo, Masahiro× Tsunoo, Takanori× 森 慎一郎× 遠藤 真広× 角尾 卓紀 |
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| 抄録 | ||||||
| 内容記述タイプ | Abstract | |||||
| 内容記述 | We have developed a prototype of 4-dimensional (4D) CT-scanner that employs continuous rotation of cone-beam, the number of elements are 912 channels x 256 segments; element size is approximately 1mm x 1mm. Scanning time is 1.0sec/rotation. Data sampling rate is 900 views (frames)/sec. The potential drawback of cone beam CT is a larger amount of scattered x-rays than conventional CT-scanner. Our purpose in this work was to estimate scattered-to-primary ratio (S/P) and observe its effects on the reconstructed images as variation of a beam width (5-128mm). S/P was measured by scanning cylindrical water phantom and interrupting the primary with Pb disk. The effects of scattered radiation on the images was evaluated with noise and uniformity of CT number, the low contrast detectability and the differences of CT number between air cavity in the water phantom and air region outside it. \nThough S/P increased as the beam width became wider, noise and uniformity of CT numbers depended little on the beam width. Low contrast detectability did not depend on it. However CT numbers differed 38 at 5mm beam width and 67 at 128mm beam width between the air cavity and the air region outside. S/P of 200mm-diam-water phantom for 120kVp was approximately 8% (128mm beam width) and approximately 1% (10mm beam width). The results suggested that scattered radiation seemed little effect on image quality except quantitativeness of CT-number in 4D CT. |
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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 | RSNA(Radiological Society of North America) | |||||
| 発表年月日 | ||||||
| 日付 | 2003-12-06 | |||||
| 日付タイプ | Issued | |||||
