Hickethier Tilman, Iuga Andra-Iza, Lennartz Simon, Hauger Myriam, Byrtus Jonathan, Luetkens Julian A, Haneder Stefan, Maintz David, Doerner Jonas
Institute of Diagnostic and Interventional Radiology, University of Bonn, Bonn, Germany.
J Comput Assist Tomogr. 2018 May/Jun;42(3):350-356. doi: 10.1097/RCT.0000000000000711.
We aimed to determine optimal window settings for conventional polyenergetic (PolyE) and virtual monoenergetic images (MonoE) derived from abdominal portal venous phase computed tomography (CT) examinations on a novel dual-layer spectral-detector CT (SDCT).
From 50 patients, SDCT data sets MonoE at 40 kiloelectron volt as well as PolyE were reconstructed and best individual window width and level values manually were assessed separately for evaluation of abdominal arteries as well as for liver lesions. Via regression analysis, optimized individual values were mathematically calculated. Subjective image quality parameters, vessel, and liver lesion diameters were measured to determine influences of different W/L settings.
Attenuation and contrast-to-noise values were significantly higher in MonoE compared with PolyE. Compared with standard settings, almost all adjusted W/L settings varied significantly and yielded higher subjective scoring. No differences were found between manually adjusted and mathematically calculated W/L settings.
PolyE and MonoE from abdominal portal venous phase SDCT examinations require appropriate W/L settings depending on reconstruction technique and assessment focus.
我们旨在确定在新型双层光谱探测器CT（SDCT）上，腹部门静脉期计算机断层扫描（CT）检查所获得的传统多能（PolyE）和虚拟单能图像（MonoE）的最佳窗口设置。
对50例患者的SDCT数据集进行重建，分别获得40千电子伏特的MonoE以及PolyE，并分别手动评估用于评估腹部动脉以及肝脏病变的最佳个体窗宽和窗位值。通过回归分析，以数学方法计算优化后的个体值。测量主观图像质量参数、血管和肝脏病变直径，以确定不同窗宽/窗位（W/L）设置的影响。
与PolyE相比，MonoE中的衰减和对比噪声值显著更高。与标准设置相比，几乎所有调整后的W/L设置均有显著差异，并产生更高的主观评分。手动调整和数学计算的W/L设置之间未发现差异。
腹部门静脉期SDCT检查的PolyE和MonoE需要根据重建技术和评估重点设置合适的W/L。
