Praël Isabelle, Wuest Wolfgang, Heiss Rafael, Wiesmueller Marco, Kopp Markus, Uder Michael, May Matthias S
Department of Radiology, University Hospital Erlangen, 91054 Erlangen, Germany.
Faculty of Medicine, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
Diagnostics (Basel). 2021 Oct 26;11(11):1989. doi: 10.3390/diagnostics11111989.
Pulmonary arterial dual-energy (aDE) CT is an established technique for evaluating pulmonary perfusion blood volume (PBV). As DECT protocols are increasingly used for thoraco-abdominal CT, this study assessed image quality and clinical findings in portal-venous phase dual-energy (vDE) CT and compared it to aDE. In 95 patients, vDE-CT was performed using a dual-source scanner (70/Sn150 kV, 560/140 ref.mAs). Pulmonary triggered aDE-CT served as reference ( = 94). PBV was reconstructed using a dedicated algorithm. Mean relative attenuation was measured in the pulmonary trunk, aorta, and segmented lung parenchyma. A distribution ratio (DL) between vessels and parenchyma was calculated to assess the iodine uptake of the lung parenchyma. Subjective overall diagnostic image quality was assessed for PBV images on a five-point Likert scale. Image artifacts were classified into five groups based on scale rating and compared between vDE and aDE. Pathological findings were correlated with the anatomical image datasets. Mean relative attenuation of the lung parenchyma was comparable in both groups (vDE: 23 ± 6 HU and aDE: 22 ± 7 HU), but significantly lower in the vessels of vDE. Therefore, iodine uptake of the lung parenchyma was significantly higher in vDE (DL: 10% vs. 8%, < 0.01). The subjective overall image quality of the PBV images was comparable ( = 0.5). Rotation and streak artifacts were found in most of the patients (>86%, both > 0.6). Dual-source artifacts were found in only a few patients in both groups (vDE 5%, aDE 7%, = 0.5). Recess and subpleural artifacts were increased in vDE (vDE 53/27%, aDE 24/7%, both < 0.001). Pathological findings were found in 19% of the vDE patients and 59% of the aDE patients. Comparable objective and subjective image quality of lung perfusion can be obtained in vDE and aDE. Iodine uptake of the lung parenchyma is increased in vDE compared to aDE, suggesting an interstitial pooling effect. Knowledge of the different appearances of artifacts will aid in the interpretation of the images. Additional clinical information about the lung parenchyma can be provided by PBV evaluation in vDE.
肺动脉双能量（aDE）CT是一种用于评估肺灌注血容量（PBV）的成熟技术。随着双能量CT协议越来越多地用于胸腹CT检查，本研究评估了门静脉期双能量（vDE）CT的图像质量和临床发现，并将其与aDE进行比较。对95例患者使用双源扫描仪（70/Sn150 kV，560/140参考毫安秒）进行vDE-CT检查。以肺触发aDE-CT作为对照（=94）。使用专用算法重建PBV。在肺动脉主干、主动脉和分段肺实质中测量平均相对衰减。计算血管与实质之间的分布比（DL），以评估肺实质的碘摄取。根据五点李克特量表对PBV图像的主观整体诊断图像质量进行评估。根据量表评分将图像伪影分为五组，并在vDE和aDE之间进行比较。将病理结果与解剖图像数据集进行关联。两组肺实质的平均相对衰减相当（vDE：23±6 HU，aDE：22±7 HU），但vDE血管中的平均相对衰减显著更低。因此，vDE中肺实质的碘摄取显著更高（DL：10%对8%，<0.01）。PBV图像的主观整体图像质量相当（=0.5）。大多数患者（>86%，两者>0.6）出现旋转和条纹伪影。两组中只有少数患者出现双源伪影（vDE 5%，aDE 7%，=0.5）。vDE中隐窝和胸膜下伪影增加（vDE 53/27%，aDE 24/7%，两者<0.001）。19%的vDE患者和59%的aDE患者发现病理结果。vDE和aDE在肺灌注方面可获得相当的客观和主观图像质量。与aDE相比，vDE中肺实质的碘摄取增加，提示存在间质聚集效应。了解伪影的不同表现将有助于图像解读。vDE中的PBV评估可为肺实质提供额外的临床信息。
