中华放射医学与防护杂志
中華放射醫學與防護雜誌
중화방사의학여방호잡지
Chinese Journal of Radiological Medicine and Protection
2014年
6期
441-445
,共5页
罗素明%何志坚%李开宝%薛娴
囉素明%何誌堅%李開寶%薛嫻
라소명%하지견%리개보%설한
非参考条件%TLD%光子线束和电子线束%平行板电离室%吸收剂量
非參攷條件%TLD%光子線束和電子線束%平行闆電離室%吸收劑量
비삼고조건%TLD%광자선속화전자선속%평행판전리실%흡수제량
Non-reference condition%TLD%Photon and electron beams%Plane parallel chamber%Absorbed dose
目的 研究用热释光剂量计(TLD)核查非参考条件下光子线束和电子线束剂量学参数方法.方法 用60Coγ线束,高能X射线束和电子线束,开展TLD分散性、非线性剂量响应、衰退、能量和有机玻璃支架(IAEA提供)等校正实验,建立估算TLD水中光子线束和电子线束吸收剂量方法.选择了60 Co,6、10、15和18 MV光子线束(离轴),剂量随着照射野和30°楔形角度变化研究;选择了6和10 MV光子线,剂量随着源皮距,照射野和楔形角度变化进行可靠性研究;选择了9和15 MeV电子线,剂量随着源皮距离变化进行可靠性研究.结果 用建立的TLD方法,估算非参考条件下光子线束(离轴)研究结果,相对偏差在-0.1％ ～7.2％(IAEA要求不大于±7.0％)范围内.非参考条件光子线束(轴上)验证研究结果,相对偏差在0.1％ ～7.0％范围内;参考和非参考条件电子线束验证研究结果,相对偏差为0 ～4.7％(IAEA要求不大于±5.0％)范围内.结论 用TLD核查放射治疗非参考条件临床的剂量学参数方便准确,经在医院做可靠性验证,对高能电子线束,用平行板电离室校准吸收剂量,用TLD验证,效果很好.
目的 研究用熱釋光劑量計(TLD)覈查非參攷條件下光子線束和電子線束劑量學參數方法.方法 用60Coγ線束,高能X射線束和電子線束,開展TLD分散性、非線性劑量響應、衰退、能量和有機玻璃支架(IAEA提供)等校正實驗,建立估算TLD水中光子線束和電子線束吸收劑量方法.選擇瞭60 Co,6、10、15和18 MV光子線束(離軸),劑量隨著照射野和30°楔形角度變化研究;選擇瞭6和10 MV光子線,劑量隨著源皮距,照射野和楔形角度變化進行可靠性研究;選擇瞭9和15 MeV電子線,劑量隨著源皮距離變化進行可靠性研究.結果 用建立的TLD方法,估算非參攷條件下光子線束(離軸)研究結果,相對偏差在-0.1％ ～7.2％(IAEA要求不大于±7.0％)範圍內.非參攷條件光子線束(軸上)驗證研究結果,相對偏差在0.1％ ～7.0％範圍內;參攷和非參攷條件電子線束驗證研究結果,相對偏差為0 ～4.7％(IAEA要求不大于±5.0％)範圍內.結論 用TLD覈查放射治療非參攷條件臨床的劑量學參數方便準確,經在醫院做可靠性驗證,對高能電子線束,用平行闆電離室校準吸收劑量,用TLD驗證,效果很好.
목적 연구용열석광제량계(TLD)핵사비삼고조건하광자선속화전자선속제량학삼수방법.방법 용60Coγ선속,고능X사선속화전자선속,개전TLD분산성、비선성제량향응、쇠퇴、능량화유궤파리지가(IAEA제공)등교정실험,건립고산TLD수중광자선속화전자선속흡수제량방법.선택료60 Co,6、10、15화18 MV광자선속(리축),제량수착조사야화30°설형각도변화연구;선택료6화10 MV광자선,제량수착원피거,조사야화설형각도변화진행가고성연구;선택료9화15 MeV전자선,제량수착원피거리변화진행가고성연구.결과 용건립적TLD방법,고산비삼고조건하광자선속(리축)연구결과,상대편차재-0.1％ ～7.2％(IAEA요구불대우±7.0％)범위내.비삼고조건광자선속(축상)험증연구결과,상대편차재0.1％ ～7.0％범위내;삼고화비삼고조건전자선속험증연구결과,상대편차위0 ～4.7％(IAEA요구불대우±5.0％)범위내.결론 용TLD핵사방사치료비삼고조건림상적제량학삼수방편준학,경재의원주가고성험증,대고능전자선속,용평행판전리실교준흡수제량,용TLD험증,효과흔호.
Objective To develop a methodology for auditing dosimetric parameters using TLD for photon and electron beams in non-reference conditions.Methods The correction experiments have been developed for non-linear dose response,PAAM holder,energy,fading and dispersion using TLD for 60Co γ-ray,high energy X-ray and electron beams.The measuring method was set up for absorbed dose estimation by TLDs in water.3 photon beams and 2 electron beams were selected for research purposes,and 5 photon beams and 4 electron beams for reliability research.Results The research results were evaluated for60Co source,6,10,15 and 18 MV photon beams in non-reference conditions at off-axis,with the relative deviation within-0.1％-7.2％ at-off axis (IAEA's acceptable deviation:± 7.0％).The verification results were evaluated for 5 photon beams in non-reference conditions at on-axis,with the relative deviation are within 0.1％-7.0％.The verification results were evaluated for 4 electron beams in non-reference conditions,with the relative deviation within 0-4.7％ (IAEA's acceptable deviation:±5.0％).Conclusions It is convenient and accurate to use TLD method for quality audits for clinic dosimetry parameters in radiotherapy.Two kinds of IAEA TLD holders are feasible for use in TLD audits.Absorbed doses for high energy electron beam were corrected using plane parallel chambers and verified using TLD,with good results obtained.
