Department of Radiology, Eunpyeong St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 1021, Tongil-ro, Eunpyeong-gu, Seoul, 03312, Republic of Korea.
Department of Radiology, Eunpyeong St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 1021, Tongil-ro, Eunpyeong-gu, Seoul, 03312, Republic of Korea.
Eur J Radiol. 2021 Jul;140:109741. doi: 10.1016/j.ejrad.2021.109741. Epub 2021 Apr 29.
To evaluate the difference in liver density and to compare the performance to diagnose fatty liver between true noncontrast (TNC) images and virtual noncontrast (VNC) images generated from dual-energy CT (DECT).
Patients who underwent liver dynamic DECT and MRI were included (n = 49). Two observers measured the liver and spleen densities on TNC images and three VNC images from the arterial, portal and delayed phases of DECT (VNCa, VNCp and VNCd, respectively). The liver-minus-spleen density (density L-S) and liver-to-spleen ratio (density L/S) were calculated. The CT parameters were compared between normal liver patients and fatty liver patients by using the independent t-test. Differences and agreements between measurements on TNC images and VNC images were evaluated by using the paired t-test and Bland-Altman analysis. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic performance of CT parameters for diagnosing fatty liver.
All CT parameters measured on TNC and VNC images were significantly higher in normal liver patients than in fatty liver patients. Although the mean liver densities on VNC images were significantly lower than those on TNC images, all CT parameters showed good agreement between TNC images and VNC images. The diagnostic performances of CT parameters on VNC images were not significantly different from those on TNC images.
Although the liver and spleen density on VNC images was significantly lower than that on TNC images, the diagnostic performances of CT parameters on three VNC images from multiple phases were similar to those on TNC images for diagnosing fatty liver.
评估肝脏密度的差异，并比较真实无对比（TNC）图像和双能 CT（DECT）生成的虚拟无对比（VNC）图像在诊断脂肪肝方面的性能。
纳入了行肝脏动态 DECT 和 MRI 检查的患者（n=49）。两位观察者分别在 TNC 图像和 DECT 的动脉期、门静脉期和延迟期的三个 VNC 图像（VNCa、VNCp 和 VNCd）上测量肝脏和脾脏的密度。计算肝-脾密度差（密度 L-S）和肝脾比（密度 L/S）。采用独立 t 检验比较正常肝脏患者和脂肪肝患者的 CT 参数。采用配对 t 检验和 Bland-Altman 分析评估 TNC 图像和 VNC 图像上测量值的差异和一致性。采用受试者工作特征（ROC）曲线分析评估 CT 参数诊断脂肪肝的性能。
TNC 和 VNC 图像上测量的所有 CT 参数在正常肝脏患者中均显著高于脂肪肝患者。尽管 VNC 图像上的平均肝脏密度显著低于 TNC 图像，但所有 CT 参数在 TNC 图像和 VNC 图像之间均具有良好的一致性。VNC 图像上的 CT 参数的诊断性能与 TNC 图像上的无显著差异。
尽管 VNC 图像上的肝脏和脾脏密度显著低于 TNC 图像，但多期 VNC 图像上的 CT 参数的诊断性能与 TNC 图像相似，可用于诊断脂肪肝。
