Assessment of coronary stents using 40-detector row CT: comparison with 16-detector row CT in vitro

To evaluate the performance of 40-detector row computed tomography (CT) in the assessment of coronary stents in comparison with 16-detector row CT.

A total of 6 vascular models (3 models without stenosis and 3 with stenosis) using 3 types of stent (Bx-Velocity, Express2, and Driver) with an approximately 3.5-mm inner diameter filled with contrast material (450 Hounsfield units) were scanned with 2 computed tomographic scanners (collimation, 16 x 0.75 and 40 x 0.625 mm). We evaluated the in-stent stenosis visually for the 6 vascular models in 4 orientations (0, 30, 60, and 90 degrees) to the z-axis of the scanner. We evaluated attenuation values of the stent lumen of the 3 patent models in the 4 orientations. The average and standard deviation of the luminal attenuation values were assessed to evaluate the degree of blooming and streak artifacts.

The visualization of the stent lumen of the vascular models at 90 degrees was improved using 40-detector row CT. For all the 3 stents, the average luminal attenuations values using 40-detector row CT were significantly lower than those using 16-detector row CT in all orientations. For all the 3 stents, the standard deviations of the luminal computed tomographic attenuation using 40-detector row CT were significantly smaller than those using 16-detector row CT in the 4 orientations to the z-axis except for Express 2 at 0 degrees.

The visualization of coronary stents is improved by the use of 40-detector row CT with reduced blooming and streak artifacts.