Peterzol A, Padovani R, Quai E, Vano E, Prieto C, Aviles P
Dipartimento di Fisica, Università di Trieste, Via Valerio 2, 34100 Trieste, Italy.
Radiat Prot Dosimetry. 2005;117(1-3):38-43. doi: 10.1093/rpd/nci709. Epub 2006 Feb 3.
The image quality (IQ) evaluation of a charge-coupled device (CCD)-based digital angiography system was assessed with respect to modulation transfer function and noise power spectrum. These values were used to calculate the system's frequency-dependent detective quantum efficiency (DQE). The X-ray image detector was an image intensifier (II) lens coupled to a CCD camera. Two measurement setups were used. Setup A is standard IQ assessment, while Setup B more closely represented clinical conditions (polymethyl methacrylate (PMMA) of varying thickness placed between the X-ray tube and II, with test object positioned between PMMA slices 30 cm from the II). Exposure parameters varied according to automatic brightness control settings. Setup B included X-ray radiation scattered by the patient-PMMA. A clinical DQE, describing the transmission of the input signal-to-noise ratio associated with both primary and secondary X-ray spectra, was defined.
基于电荷耦合器件（CCD）的数字血管造影系统的图像质量（IQ）评估是根据调制传递函数和噪声功率谱进行的。这些值用于计算系统的频率相关探测量子效率（DQE）。X射线图像探测器是一个与CCD相机耦合的图像增强器（II）镜头。使用了两种测量设置。设置A是标准的IQ评估，而设置B更接近临床情况（在X射线管和II之间放置不同厚度的聚甲基丙烯酸甲酯（PMMA），测试对象位于距II 30 cm的PMMA切片之间）。曝光参数根据自动亮度控制设置而变化。设置B包括患者-PMMA散射的X射线辐射。定义了一个临床DQE，用于描述与初级和次级X射线光谱相关的输入信噪比的传输。
