Department of Radiology, Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Songpa-gu, Seoul, Korea.
J Thorac Imaging. 2010 Nov;25(4):301-10. doi: 10.1097/RTI.0b013e3181e16232.
For the assessment of solitary pulmonary nodules (SPNs), a chest computed tomography (CT) is often performed as a combination of a nonenhanced and an enhanced scan. A nonenhanced scan is used for the detection of calcification in the SPN or lymph node, as the presence of calcification is one of the important determinants of benignity. An enhanced scan is informative in providing the degree and pattern of enhancement. In particular, the degree of enhancement of an SPN after iodine injection has been shown to be helpful in distinguishing malignant from benign nodules. Recently introduced dual-energy applications of dual-source CT simultaneously provide a virtual nonenhanced and an iodine-enhanced image from a single scan, after the administration of iodine contrast material. Therefore, a single enhanced dual-energy CT scan allows both measurement of the degree of enhancement and detection of calcifications. It may reduce radiation exposure to patients by avoiding baseline nonenhanced scans and may also reduce measurement error due to different regions of interest during the subtraction of a nonenhanced image from an enhanced image. This technique may have applications in contrast-enhanced dynamic CT and perfusion CT for the differentiation between benign and malignant lesions and the assessment of tumor angiogenesis. In this review article, we sought to address the usefulness of dual-energy CT for the assessment of SPN. In addition, we briefly review the physical principles of dual-energy CT and discuss potential future applications in patients with lung nodules.
对于孤立性肺结节（SPN）的评估，通常会进行胸部 CT 平扫加增强扫描。平扫用于检测 SPN 或淋巴结中的钙化，因为钙化的存在是良性的重要决定因素之一。增强扫描有助于提供增强程度和模式的信息。特别是，SPN 在碘注射后的增强程度有助于区分恶性和良性结节。最近推出的双源 CT 的双能量应用程序，在给予碘造影剂后，可从单次扫描中同时提供虚拟平扫和碘增强图像。因此，单次增强双能量 CT 扫描可以同时测量增强程度和检测钙化。它可以通过避免基线平扫来减少患者的辐射暴露，并且还可以减少由于在从增强图像减去平扫图像时不同的感兴趣区域而导致的测量误差。该技术可能在对比增强动态 CT 和灌注 CT 中用于区分良恶性病变和评估肿瘤血管生成方面具有应用价值。在这篇综述文章中，我们旨在探讨双能量 CT 在 SPN 评估中的作用。此外，我们还简要回顾了双能量 CT 的物理原理，并讨论了其在肺部结节患者中的潜在未来应用。
