Evaluation of coronary stents with 64-MDCT: in vitro comparison of scanners from four vendors.

OBJECTIVE

The purpose of this study was to compare 64-MDCT scanners from four vendors in the in vitro evaluation of coronary artery stents.

MATERIALS AND METHODS

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.

RESULTS

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.

CONCLUSION

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.