Biomedical Engineering, University of Florida, Gainesville, FL 32611, USA.
Med Phys. 2011 Oct;38(10):5490-9. doi: 10.1118/1.3633935.
To introduce a new skin dose mapping software system for interventional fluoroscopy dose assessment and to analyze the benefits and limitations of patient-phantom matching.
In this study, a new software system was developed for visualizing patient skin dose during interventional fluoroscopy procedures. The system works by translating the reference point air kerma to the location of the patient's skin, which is represented by a computational model. In order to orient the model with the x-ray source, geometric parameters found within the radiation dose structured report (RDSR) are used along with a limited number of in-clinic measurements. The output of the system is a visual indication of skin dose mapped onto an anthropomorphic model at a resolution of 5 mm. In order to determine if patient-dependent and patient-sculpted models increase accuracy, peak skin dose was calculated for each of 26 patient-specific models and compared with doses calculated using an elliptical stylized model, a reference hybrid model, a matched patient-dependent model and one patient-sculpted model. Results were analyzed in terms of a percent difference using the doses calculated using the patient-specific model as the true standard.
Anthropometric matching, including the use of both patient-dependent and patient-sculpted phantoms, was shown most beneficial for left lateral and anterior-posterior projections. In these cases, the percent difference using a reference model was between 8 and 20%, using a patient-dependent model between 7 and 15%, and using a patient-sculpted model between 3 and 7%. Under the table tube configurations produced errors less than 5% in most situations due to the flattening affects of the table and pad, and the fact that table height is the main determination of source-to-skin distance for these configurations. In addition to these results, several skin dose maps were produced and a prototype display system was placed on the in-clinic monitor of an interventional fluoroscopy system.
The skin dose mapping program developed in this work represents a new tool that, as the RDSR becomes available through automated export or real-time streaming, can provide the interventional physician information needed to modify behavior when clinically appropriate. The program is nonproprietary and transferable, and also functions independent to the software systems already installed on the control room workstation. The next step will be clinical implementation where the workflow will be optimized along with further analysis of real-time capabilities.
介绍一种新的用于介入透视剂量评估的皮肤剂量映射软件系统，并分析患者-体模匹配的优缺点。
本研究开发了一种新的软件系统，用于在介入透视过程中可视化患者皮肤剂量。该系统通过将参考点空气比释动能转换到患者皮肤的位置来工作，这是通过计算模型来表示的。为了使模型与 X 射线源对准，使用辐射剂量结构化报告（RDSR）中找到的几何参数以及少量临床测量值。系统的输出是将皮肤剂量映射到人体模型上的可视化指示，分辨率为 5 毫米。为了确定患者相关和患者塑造的模型是否能提高准确性，为每个 26 个患者特定模型计算了峰值皮肤剂量，并与使用椭圆形风格模型、参考混合模型、匹配的患者相关模型和一个患者塑造模型计算的剂量进行了比较。结果根据使用患者特定模型计算的剂量作为真实标准的百分比差异进行分析。
人体测量匹配，包括使用患者相关和患者塑造的体模，对于左侧侧位和前后位投影最为有益。在这些情况下，使用参考模型的百分比差异在 8%到 20%之间，使用患者相关模型的百分比差异在 7%到 15%之间，使用患者塑造模型的百分比差异在 3%到 7%之间。由于桌子和平板的扁平化影响以及桌子高度是这些配置源到皮肤距离的主要决定因素，因此在大多数情况下，桌子下的管配置产生的误差小于 5%。除了这些结果外，还生成了几个皮肤剂量图，并将原型显示系统放置在介入透视系统的临床监测器上。
本工作开发的皮肤剂量映射程序代表了一种新的工具，随着 RDSR 通过自动导出或实时流传输可用，它可以为介入医师提供在临床适当的情况下改变行为所需的信息。该程序是无专利和可转让的，并且独立于控制室工作站上已经安装的软件系统运行。下一步将是临床实施，其中将优化工作流程，并进一步分析实时功能。
