Brosi Philippe, Stuessi Anja, Verdun Francis R, Vock Peter, Wolf Rainer
Institute of Diagnostic, Interventional and Pediatric Radiology, Inselspital, University of Bern, Freiburgstrasse, Bern, Switzerland.
Radiol Phys Technol. 2011 Jul;4(2):148-55. doi: 10.1007/s12194-011-0115-4. Epub 2011 Mar 23.
The effect of copper (Cu) filtration on image quality and dose in different digital X-ray systems was investigated. Two computed radiography systems and one digital radiography detector were used. Three different polymethylmethacrylate blocks simulated the pediatric body. The effect of Cu filters of 0.1, 0.2, and 0.3 mm thickness on the entrance surface dose (ESD) and the corresponding effective doses (EDs) were measured at tube voltages of 60, 66, and 73 kV. Image quality was evaluated in a contrast-detail phantom with an automated analyzer software. Cu filters of 0.1, 0.2, and 0.3 mm thickness decreased the ESD by 25-32%, 32-39%, and 40-44%, respectively, the ranges depending on the respective tube voltages. There was no consistent decline in image quality due to increasing Cu filtration. The estimated ED of anterior-posterior (AP) chest projections was reduced by up to 23%. No relevant reduction in the ED was noted in AP radiographs of the abdomen and pelvis or in posterior-anterior radiographs of the chest. Cu filtration reduces the ESD, but generally does not reduce the effective dose. Cu filters can help protect radiosensitive superficial organs, such as the mammary glands in AP chest projections.
研究了铜（Cu）过滤对不同数字X射线系统图像质量和剂量的影响。使用了两个计算机X线摄影系统和一个数字X射线探测器。用三个不同的聚甲基丙烯酸甲酯模块模拟儿童身体。在60、66和73 kV的管电压下，测量了厚度为0.1、0.2和0.3 mm的铜滤过器对入射表面剂量（ESD）和相应有效剂量（EDs）的影响。使用自动分析仪软件在对比细节体模中评估图像质量。厚度为0.1、0.2和0.3 mm的铜滤过器分别使ESD降低了25%-32%、32%-39%和40%-44%，其范围取决于各自的管电压。随着铜滤过增加，图像质量没有持续下降。前后位（AP）胸部投照的估计有效剂量最多降低了23%。在腹部和骨盆的AP X线片或胸部后前位X线片中，未发现有效剂量有相关降低。铜滤过可降低ESD，但一般不会降低有效剂量。铜滤过器有助于保护对辐射敏感的浅表器官，如AP胸部投照中的乳腺。
