Kelcz F, Zink F E, Peppler W W, Kruger D G, Ergun D L, Mistretta C A
Department of Radiology, University of Wisconsin, Madison 53792-3252.
AJR Am J Roentgenol. 1994 Feb;162(2):271-8. doi: 10.2214/ajr.162.2.8310908.
We evaluated a single-exposure, phosphor-plate, dual-energy imaging device that produces, in addition to conventional chest radiographs, both tissue- and bone-selective images. Our purpose was to determine whether dual-energy radiography was more accurate than routine chest radiography for detection and characterization of pulmonary nodules.
Two hundred patients undergoing chest CT were asked to volunteer to have dual-energy and conventional chest radiographs obtained immediately before or after their CT scan. Radiographs from a subset of 50 of these patients with 116 CT-detected nodules and 10 patients with normal findings on CT scans of the chest were presented to the observers for the nodule detection study. Similarly, radiographs from a subset of 29 patients with 20 calcified and 20 uncalcified nodules were presented to five observers to determine nodule calcification. Dual-energy images were produced by filtering the X-ray tube output with a gadolinium sheet while using a multiple phosphor plate receptor. A dual-energy triad of images consisting of a conventional image, a tissue-selective image, and a bone-selective image were produced. The conventional chest radiographs and dual-energy image sets were presented to observers in random order. Data from a free response receiver operating curve and a receiver operating curve were generated for nodule detection and characterization, respectively.
By using the dual-energy images, all five observers improved their ability to diagnose pulmonary nodules (p = .0005) and to characterize nodules as calcified (p = .005).
By eliminating rib shadows with tissue-selective images and enhancing calcified structures with bone-selective images, dual-energy chest radiography improved the ability of all observers, regardless of expertise, to detect and characterize pulmonary nodules.
我们评估了一种单次曝光的磷光板双能成像设备，该设备除了能生成传统胸部X光片外，还能生成组织选择性和骨选择性图像。我们的目的是确定双能X线摄影在检测和鉴别肺结节方面是否比常规胸部X光摄影更准确。
邀请200名接受胸部CT检查的患者自愿在CT扫描前或后立即进行双能和传统胸部X光检查。从这200名患者中选取了50名，其中116个结节经CT检测发现，另外10名患者胸部CT扫描结果正常，并将他们的X光片提供给观察者进行结节检测研究。同样，从29名患者中选取X光片，这些患者有20个钙化结节和20个未钙化结节，并将其提供给5名观察者以确定结节钙化情况。双能图像是通过使用钆片过滤X射线管输出，同时使用多磷光板接收器生成的。生成了由传统图像、组织选择性图像和骨选择性图像组成的双能三联图像。传统胸部X光片和双能图像集以随机顺序呈现给观察者。分别针对结节检测和鉴别生成了自由反应接收器操作曲线和接收器操作曲线的数据。
通过使用双能图像，所有5名观察者诊断肺结节的能力（p = 0.0005）以及将结节鉴别为钙化结节的能力（p = 0.005）均有所提高。
通过组织选择性图像消除肋骨阴影，并通过骨选择性图像增强钙化结构，双能胸部X光摄影提高了所有观察者（无论专业水平如何）检测和鉴别肺结节的能力。
