Wolf Florian, Cademartiri Filippo, Loewe Christian, Stadler Alfred, Weber Michael, Lammer Johannes, Feuchtner Gudrun M
Division of Cardiovascular and Interventional Radiology, Department of Radiology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.
AJR Am J Roentgenol. 2009 Sep;193(3):787-94. doi: 10.2214/AJR.08.1897.
The purpose of this study was to compare 64-MDCT scanners from four vendors in the in vitro evaluation of coronary artery stents.
Twelve coronary artery stents (nominal outer diameter, 2.5-5.0 mm) oriented in the z-axis were placed in a combined cardiac-chest phantom and imaged with 64-MDCT scanners from four vendors. Quantitative image quality parameters, including artificial in-stent luminal narrowing, image noise, and artificial in-stent luminal attenuation were measured on longitudinal and axial reformations. Imaging of stents with a luminal diameter of 3 mm or less and that of stents with a diameter greater than 3 mm also were compared.
Artificial in-stent luminal narrowing was not different among the four vendors (range, 37-42%) on longitudinal reformations. Image noise inside the stent was significantly greater for one vendor (Siemens Healthcare; SD, 48 HU) than for the others (SD range, 21-26 HU) on longitudinal but not on axial images. For the same vendor, artificial in-stent luminal attenuation was significantly lower than for the other vendors. For all vendors, image noise inside the stent was significantly greater on axial than on longitudinal reformations (p < 0.001), and artificial luminal attenuation was significantly greater for all but one vendor (GE Healthcare). Stents 3 mm and narrower had significantly greater artificial luminal narrowing and artificial luminal attenuation (p < 0.05) than those with a diameter greater than 3 mm.
For longitudinal reformations, scanners from the four leading vendors do not differ in artificial luminal narrowing, but there are differences in artificial luminal attenuation and image noise. The quality of images of the in-stent lumen is better on longitudinal reformations and for stents with a diameter greater than 3 mm. Except for image noise, differences between axial and longitudinal reformations are vendor specific.
本研究旨在比较四家厂商的64层螺旋CT扫描仪对冠状动脉支架的体外评估情况。
将12个沿z轴方向放置的冠状动脉支架（标称外径2.5 - 5.0 mm）置于心脏胸部联合体模中，并用四家厂商的64层螺旋CT扫描仪进行成像。在纵向和轴向重建图像上测量定量图像质量参数，包括人工支架内管腔狭窄、图像噪声和人工支架内管腔衰减。还比较了管腔直径3 mm及以下的支架和直径大于3 mm的支架的成像情况。
在纵向重建图像上，四家厂商的人工支架内管腔狭窄情况无差异（范围为37% - 42%）。在纵向图像而非轴向图像上，一家厂商（西门子医疗；标准差，48 HU）的支架内图像噪声显著高于其他厂商（标准差范围为21 - 26 HU）。对于同一厂商，其人工支架内管腔衰减显著低于其他厂商。对于所有厂商，支架内图像噪声在轴向重建图像上显著高于纵向重建图像（p < 0.001），除一家厂商（通用电气医疗）外，所有厂商的人工管腔衰减均显著更高。直径3 mm及以下的支架的人工管腔狭窄和人工管腔衰减显著高于直径大于3 mm的支架（p < 0.05）。
对于纵向重建，四大领先厂商的扫描仪在人工管腔狭窄方面无差异，但在人工管腔衰减和图像噪声方面存在差异。支架内管腔的图像质量在纵向重建以及直径大于3 mm的支架上更好。除图像噪声外，轴向和纵向重建之间的差异因厂商而异。
