Rippel Katharina, Decker Josua A, Luitjens Jan, Habeeballah Osama, Bette Stefanie, Braun Franziska, Kroencke Thomas J, Scheurig-Muenkler Christian
Diagnostic and Interventional Radiology, University Hospital Augsburg, Faculty of Medicine, University of Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany.
Centre for Advanced Analytics and Predictive Sciences (CAAPS), University of Augsburg, Universitätsstr. 2, 86159 Augsburg, Germany.
Diagnostics (Basel). 2024 Dec 17;14(24):2843. doi: 10.3390/diagnostics14242843.
The aim of this study was to assess the possibility of image improvement of ECG-gated, high-pitch computed tomography angiography (CTA) of the thoracoabdominal aorta before transaortic valve replacement (TAVR) on a novel dual-source photon-counting detector CT (PCD-CT) in the setting of suboptimal low-contrast attenuation.
Continuously examined patients who underwent an ECG-gated, high-pitch CTA of the aorta on a PCD-CT with a contrast decrease of at least 50% between the ascending aorta and the common femoral arteries (CFA) were included. Patient characteristics were documented. Virtual monoenergetic imaging (VMI) reconstructions with three keV settings were generated. CT values and noise were measured for five vascular segments of the aorta and the CFA. Signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were calculated. Two independent board-certified radiologists rated the images with the focus on vascular attenuation, vessel sharpness, and image quality using a 5-point Likert scale.
Fifty-five patients (mean age 77.4 ± 8.5 years; 15 women) were included. The SNR was significantly higher at 40 and 45 keV VMI compared to reference 70 keV ( < 0.001 and = 0.005, respectively). The same was shown for the CNR ( < 0.001 and = 0.0049, respectively). Subjective image evaluation showed a significant increase in vessel attenuation in the lower keV reconstructions, while the overall image quality decreased only slightly. Furthermore, 50% (8/16) of primarily non-diagnostic scans were considered diagnostic when using low-keV reconstructions ( > 0.05).
ECG-gated CTA of the aorta in high-pitch mode on PCD-CT with suboptimal contrast enhancement at the level of the CFA can be salvaged by using low-keV VMI. This implies the possibility of radiation dose reduction by eliminating the need for repeat scans.
本研究的目的是评估在低对比度衰减欠佳的情况下，使用新型双源光子计数探测器CT（PCD-CT）对经主动脉瓣置换术（TAVR）前的胸腹主动脉进行心电图门控、高螺距计算机断层扫描血管造影（CTA）时改善图像质量的可能性。
纳入在PCD-CT上接受主动脉心电图门控、高螺距CTA检查且升主动脉与股总动脉（CFA）之间对比剂减少至少50%的连续检查患者。记录患者特征。生成具有三种keV设置的虚拟单能量成像（VMI）重建图像。测量主动脉和CFA的五个血管节段的CT值和噪声。计算信噪比（SNR）和对比噪声比（CNR）。两名独立的获得委员会认证的放射科医生使用5分李克特量表对图像进行评分，重点关注血管衰减、血管清晰度和图像质量。
纳入55例患者（平均年龄77.4±8.5岁；15名女性）。与参考70keV相比，40keV和45keV VMI时的SNR显著更高（分别为<0.001和=0.005）。CNR情况相同（分别为<0.001和=0.0049）。主观图像评估显示，较低keV重建时血管衰减显著增加，而整体图像质量仅略有下降。此外，使用低keV重建时，50%（8/16）最初非诊断性扫描被认为具有诊断价值（>0.05）。
在CFA水平对比增强欠佳的情况下，PCD-CT上高螺距模式的主动脉心电图门控CTA可通过使用低keV VMI挽救。这意味着无需重复扫描从而有可能降低辐射剂量。
