高级虚拟单能量成像：门静脉期双能量 CT 对比增强中改善肌肉内病变的可视化和鉴别诊断。

Advanced Virtual Monoenergetic Imaging: Improvement of Visualization and Differentiation of Intramuscular Lesions in Portal-Venous-phase Contrast-enhanced Dual-energy CT.

机构信息

Department of Diagnostic and Interventional Radiology, University Hospital Tuebingen, Hoppe-Seyler-Strasse 3, 72076 Tuebingen, Germany.

Department of Diagnostic and Interventional Neuroradiology, University Hospital Tuebingen, Tuebingen, Germany.

出版信息

Acad Radiol. 2019 Nov;26(11):1457-1465. doi: 10.1016/j.acra.2019.02.014. Epub 2019 Mar 14.

DOI:10.1016/j.acra.2019.02.014

PMID:30879946

Abstract

PURPOSE

To evaluate the effect of advanced monoenergetic imaging (MEI+) postprocessing algorithm on the visualization of various intramuscular lesions on portal-venous-phase contrast-enhanced dual-energy computed tomography (DECT).

MATERIAL AND METHODS

Thirty-nine patients (64.3 ± 11.1 years; 26 males) with various intramuscular lesions ranging from malignancy, bleeding, inflammation, edematous changes, and benign neoplasms were included and underwent DECT (100/Sn150kV). Postprocessing with MEI+ technique was used to reconstruct images at four different keV levels (40, 60, 80, 100) and compared to the standard portal-venous-phase CT (CT) images. Image quality was assessed qualitatively (conspicuity, delineation, sharpness, noise, and confidence) by two independent readers using 5-point Likert scales, 5 = excellent; as well as quantitatively by calculating signal-to-noise ratios (SNR), contrast-to-noise ratios (CNR), and area under the receiver operating characteristic (ROC) curve (AUC) for lesion characterization.

RESULTS

Highest lesion enhancement and diagnostic confidence were observed in MEI+ 40 keV, with significant differences to CT (p < 0.001), as well as for malignant lesions (highest conspicuity, noise, and sharpness in MEI+ 40 keV; p < 0.001). CNR calculations revealed highest values for MEI+ 40 keV followed by 60 keV with significant differences to CT and increasing energy levels. ROC analysis showed highest diagnostic accuracy for 40-keV MEI+ datasets regarding the detection of malignant/benign lesions with AUC values of 98.9% (95%-confidence interval: 96.5, 100) and a standard error of 1.2, further AUC values decreased to 83.6% for MEI+100.

CONCLUSION

MEI+ at low keV levels can significantly improve lesion detection of benign versus malignant intramuscular entities in patients undergoing portal-venous-phase DECT scans due to increased CNR.

摘要

目的

评估高级单能量成像（MEI+）后处理算法对门静脉期双能 CT（DECT）增强后各种肌内病变可视化的影响。

材料与方法

共纳入 39 例（64.3±11.1 岁；26 例男性）不同肌内病变患者，包括恶性肿瘤、出血、炎症、水肿改变和良性肿瘤，并进行 DECT（100/Sn150kV）检查。采用 MEI+技术在 4 个不同 keV 水平（40、60、80、100）重建图像，并与标准门静脉期 CT（CT）图像进行比较。由两位独立的读者使用 5 分李克特量表（5 分=优秀）对图像质量进行定性评估（清晰度、轮廓、锐度、噪声和信心），并通过计算信噪比（SNR）、对比噪声比（CNR）和受试者工作特征（ROC）曲线下面积（AUC）进行定量评估，以对病变特征进行评估。

结果

MEI+40keV 时观察到最高的病变增强和诊断信心，与 CT 相比差异有统计学意义（p＜0.001），并且在恶性病变中差异更显著（MEI+40keV 时的清晰度、噪声和锐度最高；p＜0.001）。CNR 计算显示 MEI+40keV 时的数值最高，其次是 60keV，与 CT 和能量水平的增加相比差异均有统计学意义。ROC 分析显示，MEI+40keV 数据集对检测良恶性病变的诊断准确性最高，AUC 值为 98.9%（95%置信区间：96.5，100），标准误差为 1.2，进一步降低至 83.6%用于 MEI+100keV。