WEKO3
アイテム
SPOT SCANNING USING 11C BEAMS FOR HEAVY-ION RADIOTHERAPY
https://repo.qst.go.jp/records/68149
https://repo.qst.go.jp/records/68149fda5e131-0c4a-459b-b72b-a1c4fda57ad4
| Item type | 会議発表用資料 / Presentation(1) | |||||
|---|---|---|---|---|---|---|
| 公開日 | 2005-08-17 | |||||
| タイトル | ||||||
| タイトル | SPOT SCANNING USING 11C BEAMS FOR HEAVY-ION RADIOTHERAPY | |||||
| 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 |
Urakabe, Eriko
× Urakabe, Eriko× Kanai, Tatsuaki× Kanazawa, Mitsutaka× Kitagawa, Atsushi× Tomitani, Takehiro× Suda, Mitsuru× Satou, Shinji× Noda, Kouji× Furukawa, Takuji× Mizuno, Hideyuki× Iseki, Yasushi× Inaniwa, Taku× 新谷 恵理子× 金井 達明× 金澤 光隆× 北川 敦志× 富谷 武浩× 須田 充× 佐藤 眞二× 野田 耕司× 古川 卓司× 水野 秀之× 井関 康× 稲庭 拓 |
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| 抄録 | ||||||
| 内容記述タイプ | Abstract | |||||
| 内容記述 | A scheme for spot scanning using 11C beams has been developed in order to form and verify a three-dimensionally conformal irradiation field for heavy-ion radiotherapy. With use of positron emitting 11C beams, the verification of therapeutic irradiation can be directly accomplished by observing annihilation-pair gamma rays from the stopping point in the patient. One of the features of 11C beams is the large number of the gamma rays observed at the range of the incident beam. The half-life of 11C is 20.39 min, which is appropriate for measurements using offline positron emission tomography (PET). 11C produced by a projectile-fragmentation process, however, has considerably different characteristics compared with those of the primary beam: a) low yield (less than 1% of the primary beam); b) wide momentum spread (2%); c) large beam size due to its large emittance (~ 40 pi mm mrad). We have to compromise the yield and the momentum spread keeping treatment planning in mind. Its low yield motivated us the use of spot scanning method, which is associated with technical difficulties. The spot beam is scanned stepwise over the tumor region by a horizontal and vertical scanning magnets and the range shifter made by PMMA plates. The beam delivery is stopped just after the prescribed dose is reached. For the precise dose management, the fast beam cut-off method is investigated and achieved a cut-off time of around 0.05 ms. During the transition time from one spot to the next one, the position and the width of each spot beam is verified. By selecting the momentum spread of a 11C beam, we could considerably decrease the distal falloff of the irradiation field, thus conserving the beam quality. To estimate and optimize the dose distribution in the irradiation field, it is essential to evaluate precisely the dose distribution of spot beams. It is pointed out that the chromatic aberration and the dispersion should be taken into account to calculate the dose distribution of 11C beams. A concave-shaped field in PMMA phantom was optimized and experimentally evaluated. In this conference, a scheme for spot scanning that uses the above-described features of 11C beams will be reported. In this study, we focus mainly on the dose estimation of 11C spot beams. |
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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 | 9th Workshop on Heavy Charged Particles in Biology and Medicine 2003 and 3rd Meeting of the European Network for Light Ion Hadron Therapy | |||||
| 発表年月日 | ||||||
| 日付 | 2003-10-05 | |||||
| 日付タイプ | Issued | |||||
