den Boer A, de Feyter P J, Hummel W A, Keane D, Roelandt J R
University Hospital Rotterdam, Department of Cardiology, The Netherlands.
Circulation. 1994 Jun;89(6):2710-4. doi: 10.1161/01.cir.89.6.2710.
Radiographic technology plays an integral role in interventional cardiology. The number of interventions continues to increase, and the associated radiation exposure to patients and personnel is of major concern. This study was undertaken to determine whether a newly developed x-ray tube deploying grid-switched pulsed fluoroscopy and extra beam filtering can achieve a reduction in radiation exposure while maintaining fluoroscopic images of high quality.
Three fluoroscopic techniques were compared: continuous fluoroscopy, pulsed fluoroscopy, and a newly developed high-output pulsed fluoroscopy with extra filtering. To ascertain differences in the quality of images and to determine differences in patient entrance and investigator radiation exposure, the radiated volume curve was measured to determine the required high voltage levels (kVpeak) for different object sizes for each fluoroscopic mode. The fluoroscopic data of 124 patient procedures were combined. The data were analyzed for radiographic projections, image intensifier field size, and x-ray tube kilovoltage levels (kVpeak). On the basis of this analysis, a reference procedure was constructed. The reference procedure was tested on a phantom or dummy patient by all three fluoroscopic modes. The phantom was so designed that the kilovoltage requirements for each projection were comparable to those needed for the average patient. Radiation exposure of the operator and patient was measured during each mode. The patient entrance dose was measured in air, and the operator dose was measured by 18 dosimeters on a dummy operator. Pulsed compared with continuous fluoroscopy could be performed with improved image quality at lower kilovoltages. The patient entrance dose was reduced by 21% and the operator dose by 54%. High-output pulsed fluoroscopy with extra beam filtering compared with continuous fluoroscopy improved the image quality, lowered the kilovoltage requirements, and reduced the patient entrance dose by 55% and the operator dose by 69%.
High-output pulsed fluoroscopy with a grid-switched tube and extra filtering improves the image quality and significantly reduces both the operator dose and patient dose.
放射成像技术在介入心脏病学中发挥着不可或缺的作用。介入手术的数量持续增加，患者和工作人员所面临的相关辐射暴露成为主要关注点。本研究旨在确定一种新开发的采用格栅切换脉冲透视和额外束流过滤的X射线管，在保持高质量透视图像的同时，是否能够降低辐射暴露。
比较了三种透视技术：连续透视、脉冲透视以及新开发的具有额外过滤功能的高输出脉冲透视。为了确定图像质量的差异以及患者入口和研究者辐射暴露的差异，测量了辐射体积曲线，以确定每种透视模式下不同物体尺寸所需的高电压水平（kV峰值）。汇总了124例患者手术的透视数据。对这些数据进行了放射摄影投影、影像增强器视野大小和X射线管千伏电压水平（kV峰值）的分析。基于该分析构建了一个参考程序。所有三种透视模式都在体模或模拟患者上对参考程序进行了测试。体模的设计使得每个投影的千伏要求与普通患者所需的要求相当。在每种模式下测量了操作者和患者的辐射暴露。在空气中测量患者入口剂量，通过在模拟操作者身上放置18个剂量计测量操作者剂量。与连续透视相比，脉冲透视在较低千伏电压下可实现更好的图像质量。患者入口剂量降低了21%，操作者剂量降低了54%。与连续透视相比，具有额外束流过滤功能的高输出脉冲透视提高了图像质量，降低了千伏要求，患者入口剂量降低了55%，操作者剂量降低了69%。
采用格栅切换管和额外过滤的高输出脉冲透视提高了图像质量，并显著降低了操作者剂量和患者剂量。
