Köhler Michael, Burg Matthias C, Bunck Alexander C, Heindel Walter, Seifarth Harald, Maintz David
Department of Clinical Radiology, University of Münster, Albert-Schweitzer-Stra β e 33, 48129 Münster, Germany.
Radiol Res Pract. 2011;2011:103873. doi: 10.1155/2011/103873. Epub 2011 Jul 18.
Purpose. To test different peripheral arterial stents using four image reconstruction approaches with respect to lumen visualization, lumen attenuation and image noise in dual-source multidetector row CT (DSCT) in vitro. Methods and Materials. 22 stents (nitinol, steel, cobalt-alloy, tantalum, platinum alloy) were examined in a vessel phantom. All stents were imaged in axial orientation with standard parameters. Image reconstructions were obtained with four different convolution kernels. To evaluate visualization characteristics of the stent, the lumen diameter, intraluminal density and noise were measured. Results. The mean percentage of the visible stent lumen diameter from the nominal stent diameter was 74.5% ± 5.7 for the medium-sharp kernel, 72.8% ± 6.4 for the medium, 70.8% ± 6.4 for the medium-smooth and 67.6% ± 6.6 for the smooth kernel. Mean values of lumen attenuation were 299.7HU ± 127 (medium-sharp), 273.9HU ± 68 (medium), 270.7HU ± 53 (medium-smooth) and 265.8HU ± 43. Mean image noise was: 54.6 ± 6.3, 20.5 ± 1.7, 16.3 ± 1.7, 14.0 ± 2 respectively. Conclusion. Visible stent lumen diameter varies depending on stent type and scan parameters. Lumen diameter visibility increases with the sharpness of the reconstruction kernel. Smoother kernels provide more realistic density measurements inside the stent lumen and less image noise.
目的。在体外双源多排CT（DSCT）中，使用四种图像重建方法测试不同的外周动脉支架，以评估管腔可视化、管腔衰减和图像噪声情况。方法与材料。在血管模型中检查了22个支架（镍钛合金、钢、钴合金、钽、铂合金）。所有支架均以标准参数进行轴向成像。使用四种不同的卷积核进行图像重建。为评估支架的可视化特征，测量了管腔直径、腔内密度和噪声。结果。对于中等锐利核，可见支架管腔直径占标称支架直径的平均百分比为74.5%±5.7，中等核为72.8%±6.4，中等平滑核为70.8%±6.4，平滑核为67.6%±6.6。管腔衰减的平均值分别为299.7HU±127（中等锐利）、273.9HU±68（中等）、270.7HU±53（中等平滑）和265.8HU±43。平均图像噪声分别为：54.6±6.3、20.5±1.7、16.3±1.7、14.0±2。结论。可见支架管腔直径因支架类型和扫描参数而异。管腔直径的可见性随重建核的锐利度增加而提高。更平滑的核在支架腔内提供更真实的密度测量且图像噪声更少。
