Liang Hongwei, Du Silin, Yan Gaowu, Zhou Yang, Yang Tianyu, Zhang Zhiwei, Luo Chenyi, Liao Hongfan, Li Yongmei
Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing, 400016, China.
Department of Radiology, Suining Central Hospital, Suining, 629000, China.
Abdom Radiol (NY). 2023 Aug;48(8):2596-2603. doi: 10.1007/s00261-023-03914-0. Epub 2023 May 20.
To evaluate the image quality and diagnostic performance for pancreatic lesion between true non-contrast (TNC) and virtual non-contrast (VNC) images obtained from the dual-energy computed tomography (DECT).
One hundred six patients with pancreatic mass underwent contrast-enhanced DECT examinations were retrospectively included in this study. VNC images of the abdomen were generated from late arterial (aVNC) and portal (pVNC) phases. For quantitative analysis, the attenuation differences and reproducibility of abdominal organs were compared between TNC and aVNC/pVNC measurements. Qualitatively image quality was assessed by two radiologists using a five-point scale, and they independently compared the detection accuracy of pancreatic lesions between TNC and aVNC/pVNC images. The volume CT dose index (CTDIvol) and size-specific dose estimates (SSDE) were recorded to evaluate the potential dose reduction when using VNC reconstruction to replace the unenhanced phase.
A total of 78.38% (765/976) of the attenuation measurement pairs were reproducible between TNC and aVNC images, and 71.0% (693/976) between TNC and pVNC images. In triphasic examinations, a total of 108 pancreatic lesions were found in 106 patients, and no significant difference in detection accuracy was found between TNC and VNC images (p = 0.587-0.957). Qualitatively, image quality was rated diagnostic (score ≥ 3) in all the VNC images. Calculated CTDIvol and SSDE reduction of about 34% could be achieved by omitting the non-contrast phase.
VNC images of DECT provide diagnostic image quality and accurate pancreatic lesions detection, which are a promising alternative to unenhanced phase with a substantial reduction of radiation exposure in clinical routine.
评估双能计算机断层扫描（DECT）获得的真实非增强（TNC）和虚拟非增强（VNC）图像对胰腺病变的图像质量和诊断性能。
本研究回顾性纳入了106例接受对比增强DECT检查的胰腺肿块患者。腹部的VNC图像由动脉晚期（aVNC）和门静脉期（pVNC）生成。对于定量分析，比较了TNC与aVNC/pVNC测量之间腹部器官的衰减差异和可重复性。两名放射科医生使用五点量表对图像质量进行定性评估，并独立比较TNC与aVNC/pVNC图像之间胰腺病变的检测准确性。记录容积CT剂量指数（CTDIvol）和特定尺寸剂量估计值（SSDE），以评估使用VNC重建替代非增强期时潜在的剂量降低情况。
TNC与aVNC图像之间共有78.38%（765/976）的衰减测量对具有可重复性，TNC与pVNC图像之间为71.0%（693/976）。在三期检查中，106例患者共发现108个胰腺病变，TNC与VNC图像之间的检测准确性无显著差异（p = 0.587 - 0.957）。定性地说，所有VNC图像的图像质量均被评为可诊断（评分≥3）。通过省略非增强期，CTDIvol和SSDE可降低约34%。
DECT的VNC图像提供了诊断图像质量并能准确检测胰腺病变，在临床常规中是一种有前景的替代非增强期的方法，可大幅减少辐射暴露。
