Normalized mean glandular dose computation from mammography using GATE: a validation study.
Normalized mean glandular dose computation from mammography using GATE: a validation study.
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使用 GATE 计算乳房 X 线摄影的标准化平均腺体剂量：一项验证研究。
DOI：
10.1088/0031-9155/58/7/2247
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发表时间：
2013
影响因子：
3.5
通讯作者：
Myronakis ME
中科院分区：
文献类型：
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作者：
Myronakis ME
平均腺体剂量（MGD）是评估乳房x光检查后剂量的价值数字。使用由蒙特卡罗计算获得的归一化MGD与测量的入射空气kerma确定交付给患者的MGD。Geant4断层成像发射应用程序（GATE）工具包是一个现代蒙特卡罗应用程序，专门为医学成像系统建模而设计。尽管世界范围内越来越多的出版物将GATE用于广泛的医学成像和治疗应用，但目前还没有办法获得标准化的MGD。在这项工作中，通过开发两个新模块，扩展了GATE工具包，为基于简单几何形状的压缩乳房模型提供规范化的MGD信息。标准化MGD值与已发表的工作进行了验证，并提供了低于0.3和大于0.6 mmAl的半值层的结果。此外，还考虑了蒙皮的厚度和成分。在用皮肤组织代替标准乳房假体周围的脂肪层后计算归一化MGD，并报告其相对差异。其他作者先前发表的工作的进一步发展促进了频谱生成。新的GATE扩展验证显示与已发表的数据非常一致，可用于评估乳房x线摄影以及更复杂的x射线成像技术的乳房剂量。皮肤厚度和成分的变化揭示了标准化MGD的实质性变化，特别是在压缩乳房厚度低于5厘米的情况下，可能需要对标准乳房模型的结构进行修订。
Mean glandular dose (MGD) is the figure of merit to assess breast dose after a mammographic acquisition. The use of normalized MGD obtained from Monte Carlo computations with measured incident air kerma determines the MGD delivered to patients. The Geant4 Application for Tomographic Emission (GATE) toolkit is a modern Monte Carlo application specifically designed for medical imaging systems modelling. Although there is an increasing number of publications using GATE worldwide for a wide range of medical imaging and therapeutic applications, there is currently no means to obtain normalized MGD. In this work, the GATE toolkit is extended, through the development of two new modules, to provide normalized MGD information for compressed breast phantoms based on simple geometries. The normalized MGD values were validated against published work and provided results at half value layers lower than 0.3 and greater than 0.6 mmAl. In addition, the skin thickness and composition were considered. Normalized MGD was computed after substitution of the adipose layer surrounding the standard breast phantom with skin tissue and the relative difference is reported. Spectrum generation was facilitated by further development of previously published work by other authors. Validation of the new GATE extension showed good agreement with published data and can be used to assess breast dose from mammographic as well as more complex x-ray imaging techniques. Changing skin thickness and composition revealed substantial changes in normalized MGD specifically for compressed breast thickness different than 5 cm and a possible revision of the structure of the standard breast model may be necessary.