Chen Zhe, Bongiorni Paul, Nath Ravinder
Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06510, USA.
Brachytherapy. 2012 Nov-Dec;11(6):476-82. doi: 10.1016/j.brachy.2011.08.009. Epub 2011 Nov 21.
To measure the dosimetric properties of the Model AgX100 ¹²⁵I source for interstitial brachytherapy.
The photon energy spectrum emitted by the AgX100 source was measured using a high-resolution germanium spectrometer customized for low-energy brachytherapy source spectrometry. The dose distribution around the source was measured using the 1×1×1 mm³ lithium fluoride thermoluminescent dosimeters in water-equivalent solid phantoms. The dosimetric parameters needed for dose calculation using the American Association of Physicists in Medicine Task Group No. 43 (TG-43) formalism were determined and compared with the results of a Monte Carlo simulation by an independent research group and with the TG-43 consensus values of the well-established model 6711 source.
It was found that (1) the photon energy spectrum emitted by the AgX100 source was nearly identical to that emitted by the model 6711, (2) the dose-rate constant determined by the photon spectrometry technique (0.957±0.037 cGy·h⁻¹·U⁻¹) and by the thermoluminescent dosimeter technique (0.995±0.066 cGy·h⁻¹·U⁻¹) was within 1.5% of the corresponding values determined for the model 6711 source, and (3) the radial dose function and the anisotropy function of the AgX100 source were also found to be similar to the consensus data established for the model 6711 source in the TG-43 update report.
A comprehensive dosimetric characterization has been carried out for the model AgX100 ¹²⁵I source. The American Association of Physicists in Medicine TG-43 dosimetry parameters for this source has been determined from the experimental data.
测量用于组织间近距离治疗的AgX100型¹²⁵I源的剂量学特性。
使用专为低能近距离治疗源光谱分析定制的高分辨率锗光谱仪测量AgX100源发射的光子能谱。在水等效固体模体中，使用1×1×1 mm³的氟化锂热释光剂量计测量源周围的剂量分布。确定了使用美国医学物理学家协会第43任务组（TG - 43）形式主义进行剂量计算所需的剂量学参数，并与独立研究小组的蒙特卡罗模拟结果以及成熟的6711型源的TG - 43共识值进行比较。
发现（1）AgX100源发射的光子能谱与6711型源发射的光子能谱几乎相同；（2）通过光子光谱技术（0.957±0.037 cGy·h⁻¹·U⁻¹）和热释光剂量计技术（0.995±0.066 cGy·h⁻¹·U⁻¹）确定的剂量率常数在为6711型源确定的相应值的1.5%以内；（3）还发现AgX100源的径向剂量函数和各向异性函数与TG - 43更新报告中为6711型源建立的共识数据相似。
已对AgX100型¹²⁵I源进行了全面的剂量学表征。已根据实验数据确定了该源的美国医学物理学家协会TG - 43剂量学参数。
