Experimental validation of dose calculation algorithms for the GliaSite RTS, a novel 125I liquid-filled balloon brachytherapy applicator.
Experimental validation of dose calculation algorithms for the GliaSite RTS, a novel 125I liquid-filled balloon brachytherapy applicator.
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GliaSite RTS（一种新型 125I 液体填充球囊近距离放射治疗施用器）剂量计算算法的实验验证。
DOI：
10.1118/1.1334608
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发表时间：
2001
期刊：
影响因子：
3.8
通讯作者：
Williamson,JF
中科院分区：
文献类型：
--
作者：
Monroe,JI;Dempsey,JF;Dorton,JA;Mutic,S;Stubbs,JB;Markman,J;Williamson,JF
本文比较了一种新型液体填充近距离放射治疗球囊施源器（GliaSite RTS）的实验测量和计算剂量率分布，该施源器设计用于治疗恶性脑肿瘤切除术腔缘。本工作旨在符合美国医学物理学家协会（AAPM）放射治疗委员会关于低能光子间质近距离放射治疗源剂量测定表征的建议[Med. Phys.25，2269-2270（1998）]。在施源器周围的冠状面进行绝对低剂量率辐射变色胶片（RCF）剂量测定。将施源器放置在固体水模体中，机加工以符合膨胀的施源器表面。结果用于验证蒙特卡罗光子输运（MCPT）模拟和点源剂量核算法在预测水剂量方面的准确性。通过将美国国家标准与技术研究所（NIST）标准品与相同小瓶和几何形状中的已知质量的放射治疗溶液（Iotrex™）相互比较来确定溶液的绝对活性。对于不与施用器接触的两个膜，发现在距离膜中心0.2-25 mm处，RCF和MCPT之间的平均一致性（指定为连续4 mm环的平均绝对偏差）在±5%范围内。对于接触导管的两张胶片，球囊表面附近的平均一致性为±14.5%和7.5%，但距离表面3.5 mm处的平均一致性提高至7.5%和6%。这些误差（在孤立像素中高达20%）可能是由于修剪损坏、污染以及与气球的一致性差造成的。在辐射剂量很低的较大距离处，观察到的差异明显大于预期。我们假设它们是由于RCF反应的剂量率依赖性。在临床相关距离上观察到简单一维路径长度半经验剂量核模型与MCPT计算之间的平均差异为1%-10%。
This paper compares experimentally measured and calculated dose‐rate distributions for a novel liquid‐filled brachytherapy balloon applicator (the GliaSite RTS), designed for the treatment of malignant brain‐tumor resection‐cavity margins. This work is intended to comply with the American Association of Physicists in Medicine (AAPM) Radiation Therapy Committee's recommendations [Med. Phys.25, 2269–2270 (1998)] for dosimetric characterization of low‐energy photon interstitial brachytherapy sources. Absolute low dose‐rate radiochromic film (RCF) dosimetry measurements were performed in coronal planes about the applicator. The applicator was placed in a solid water phantom, machined to conform to the inflated applicator's surface. The results were used to validate the accuracy of Monte Carlo photon transport (MCPT) simulations and a point‐source dose‐kernel algorithm in predicting dose to water. The absolute activity of the solution was determined by intercomparing a National Institute of Standards and Technology (NIST) standard with a known mass of radiotherapy solution (Iotrex™) in an identical vial and geometry. For the two films not in contact with applicator, the average agreement between RCF and MCPT (specified as the mean absolute deviation in successive 4 mm rings) was found to be within ±5% at distances 0.2–25 mm from the film centers. For the two films touching the catheter, the mean agreement was ±14.5% and 7.5% near the balloon surface but improving to 7.5% and 6% by 3.5 mm from the surface. These errors, as large as 20% in isolated pixels, are likely due to trim damage, contamination, and poor conformance with the balloon. At larger distances where the radiation doses were very low, the observed discrepancies were significantly larger than expected. We hypothesize that they are due to a dose‐rate dependence of the RCF response. A 1%–10% average difference between a simple one‐dimensional path‐length semiempirical dose‐kernel model and the MCPT calculations was observed over clinically relevant distances.
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影响因子：
3.8
作者：
Reinstein, LE;Gluckman, GR
通讯作者：
Gluckman, GR
含有 3-(125I)碘-4-羟基苯磺酸钠 (Iotrex) 的水溶液用于切除恶性脑肿瘤近距离治疗的生物分布和剂量测定。
影响因子：
3.4
作者：
J. Stubbs;A. Strickland;R. Frank;J. Simon;K. Mcmillan;J. Williams
通讯作者：
J. Williams
复发性高级别星形细胞瘤的手术和永久性低活性 125I 近距离治疗。
DOI：
10.1016/s0360-3016(96)80017-4
发表时间：
1996
期刊：
International journal of radiation oncology, biology, physics
影响因子：
--
作者：
J. Halligan;Keith J. Stelzer;R. Rostomily;Alexander M. Spence;Thomas W. Griffin;M. S. Berger
通讯作者：
M. S. Berger
125I 种子的剂量率测定。
影响因子：
3.8
作者：
Chiu-Tsao,ST;Anderson,LL;O'Brien,K;Sanna,R
通讯作者：
Sanna,R
DOI：
10.1016/s0360-3016(98)00215-6
发表时间：
1998-09-01
影响因子：
7
作者：
Dempsey, JF;Williams, JA;Williamson, JF
通讯作者：
Williamson, JF