In Vivo Evaluation of Carotid Artery Stents Using Multi-Detector-Row Computed Tomography Angiography: Comparison of 3 Kernels

Objective: The objective of this study was to assess the lumen visibility of carotid artery stents using multi-detector-row computed tomography (MDCT) angiography; compare medium-smooth, medium-sharp, and sharp kernels; and correlate these results to those of digital subtraction angiography (DSA). Methods: We retrospectively evaluated 52 stents from 51 patients who underwent 16- and 64-slice MDCT angiography. Lumen diameters were measured 3 times by 2 neuroradiologists, and artificial luminal narrowing was calculated. To assess detection of in-stent restenosis (>50%), 2 neuroradiologists evaluated all MDCT and DSA images. Results: Excellent intraobserver and interobserver agreements were obtained for the lumen diameter measurements (P < 0.001). Lumen diameter visibility improved, and artificial luminal narrowing decreased from the medium-smooth kernel to the sharp kernel. Visual estimation of all CT angiography using the 3 kernels showed high accuracy for detection of in-stent restenosis (>50%), compared with DSA. Conclusions: Computed tomography angiography using a sharp kernel allows for more accurate assessment of lumen visibility after carotid artery stenting.