剂量学
近距离放射治疗
材料科学
电离室
热释光剂量计
NIST公司
克尔玛
物理
核医学
电离
剂量计
医学
放射治疗
计算机科学
离子
自然语言处理
内科学
量子力学
作者
Samantha J. Simiele,B Palmer,Larry A. DeWerd
出处
期刊:Medical Physics
[Wiley]
日期:2016-06-01
卷期号:43 (6Part24): 3625-3625
被引量:2
摘要
Purpose: The establishment of an air kerma rate standard at NIST for the Xoft Axxent® electronic brachytherapy source (Axxent® source) motivated the establishment of a modified TG-43 dosimetry formalism. This work measures the modified dosimetry parameters for the Axxent® source in the absence of a treatment applicator for implementation in Xoft's treatment planning system. Methods: The dose-rate conversion coefficient (DRCC), radial dose function (RDF) values, and polar anisotropy (PA) were measured using TLD-100 microcubes with NIST-calibrated sources. The DRCC and RDF measurements were performed in liquid water using an annulus of Virtual Water™ designed to align the TLDs at the height of the anode at fixed radii from the source. The PA was measured at several distances from the source in a PMMA phantom. MCNP-determined absorbed dose energy dependence correction factors were used to convert from dose to TLD to dose to liquid water for the DRCC, RDF, and PA measurements. The intrinsic energy dependence correction factor from the work of Pike was used. The AKR was determined using a NIST-calibrated HDR1000 Plus well-type ionization chamber. Results: The DRCC was determined to be 8.6 (cGy/hr)/(µGy/min). The radial dose values were determined to be 1.00 (1cm), 0.60 (2cm), 0.42 (3cm), and 0.32 (4cm), with agreement ranging from (5.7% to 10.9%) from the work of Hiatt et al. 2015 and agreement from (2.8% to 6.8%) with internal MCNP simulations. Conclusion: This work presents a complete dataset of modified TG-43 dosimetry parameters for the Axxent® source in the absence of an applicator. Prior to this study a DRCC had not been measured for the Axxent® source. This data will be used for calculating dose distributions for patients receiving treatment with the Axxent® source in Xoft's breast balloon and vaginal applicators, and for intraoperative radiotherapy. Sources and partial funding for this work were provided by Xoft Inc. (a subsidiary of iCAD). This work was also supported by the Radiological Sciences T32 Training Grant through the University of Wisconsin-Madison Medical Physics department (5T32CA009206-37).
科研通智能强力驱动
Strongly Powered by AbleSci AI