From the Department of Abdominal and Interventional Radiology, Massachusetts General Hospital, 55 Fruit St, White Building, Room 270, Boston, MA 02114-2696.
Radiographics. 2014 May-Jun;34(3):589-612. doi: 10.1148/rg.343135041.
Dual-energy computed tomographic (DECT) technology offers enhanced capabilities that may benefit oncologic imaging in the abdomen. By using two different energies, dual-energy CT allows material decomposition on the basis of energy-dependent attenuation profiles of specific materials. Although image acquisition with dual-energy CT is similar to that with single-energy CT, comprehensive postprocessing is able to generate not only images that are similar to single-energy CT (SECT) images, but a variety of other images, such as virtual unenhanced (VUE), virtual monochromatic (VMC), and material-specific iodine images. An increase in the conspicuity of iodine on low-energy VMC images and material-specific iodine images may aid detection and characterization of tumors. Use of VMC images of a desired energy level (40-140 keV) improves lesion-to-background contrast and the quality of vascular imaging for preoperative planning. Material-specific iodine images enable differentiation of hypoattenuating tumors from hypo- or hyperattenuating cysts and facilitate detection of isoattenuating tumors, such as pancreatic masses and peritoneal disease, thereby defining tumor targets for imaging-guided therapy. Moreover, quantitative iodine mapping may serve as a surrogate biomarker for monitoring effects of the treatment. Dual-energy CT is an innovative imaging technique that enhances the capabilities of CT in evaluating oncology patients.
双能 CT 技术提供了增强的功能，可能有益于腹部肿瘤成像。通过使用两种不同的能量，双能 CT 允许根据特定材料的能量依赖性衰减特性进行物质分解。尽管双能 CT 的图像采集与单能 CT 相似，但全面的后处理不仅能够生成与单能 CT（SECT）图像相似的图像，还能够生成各种其他图像，如虚拟非增强（VUE）、虚拟单能（VMC）和物质特异性碘图像。在低能 VMC 图像和物质特异性碘图像上碘的对比度增加可能有助于肿瘤的检测和特征描述。使用所需能量水平（40-140keV）的 VMC 图像可提高病变与背景的对比度，并改善血管成像的质量，从而进行术前规划。物质特异性碘图像可区分低衰减肿瘤与低或高衰减囊肿，并有助于检测等衰减肿瘤，如胰腺肿块和腹膜疾病，从而为成像引导治疗定义肿瘤靶标。此外，定量碘映射可用作监测治疗效果的替代生物标志物。双能 CT 是一种创新的成像技术，可增强 CT 评估肿瘤患者的能力。
