To evaluate in vitro stent lumen visibility of coronary stents in a second- and third-generation dual-source CT system at 100 and 120kVp tube potential.

Twenty-six coronary stents ranging from 2.25 to 4.0mm diameter were implanted in a coronary vessel phantom. Scans were performed at 100 and 120kVp tube potential. Evaluation was performed using a medium-sharp kernel in both systems (B46f in the second-generation and Bv49 in the third-generation model) and a sharp (Bv59) convolution kernel optimized for vascular imaging in the third-generation CT. Stent evaluation was performed solely with axial reformations and with a fixed window setting of 1500 HU width and a defined center of 300 HU. Visible...

Median visible stent lumen diameter on the second-generation system was higher at 120kVp with a median of 62.0% compared to 56.3% at 100kVp (p<0.001). Median visible diameter in the third-generation system was significantly higher applying the Bv49 kernel with 66.7% at 120kVp and 61.1% at 100kVp (both p<0.001). When applying the Bv59 kernel, visible stent lumen further increased to 69.3% at 120kVp (p=0.007)and 66.7% at 100kVp (p<0.001; Figure 2). For demonstration purposes, these differences are illustrated on longitudinal multiplanar reformationsin Figure 3.

Third-generation dual-source CT provides superior stent lumen visibility both at equivalent and reduced tube potential of 100kVp when compared to 120kVp on a second-generation system.