Objective To assess lumen visibility of coronary stents by 64-slice computed tomography （CT） coronary angiography

and determine the value of 64-slice CT in non-invasive detecting of in-stent restenosis after coronary artery stent implantation. Methods Totally

60 patients （54 males

aged 57.0±12.7 years） and 105 stents were investigated by 64-slice CT at a mean interval of 20.0±16.6 months after coronary stents implantation. Axial multi-planar reconstruction images of the stents and curved-planar reconstruction images through the median of the stents were reconstructed for evaluating stent image quality on a 5-point scale （1=excellent

5=non assessable）

and stent lumen diameter was detected. Conventional coronary angiography was performed in 18 patients

and 32 stents were evaluated. Results Image quality was good to excellent on average （score 1.71±0.76）. Stent image quality score was correlated to heart rate （r=0.281

P<0.01） and stent diameter （r=-0.480

P<0.001）. All the stents were assessable in lumen visibility with an average visible lumen diameter percentage of 60.7%±13.6%. Visible lumen diameter percentage was correlated to heart rate （r=-0.193

P<0.05）

stent diameter （r=0.403

P<0.001）

and stent image quality score （r=-0.500

P<0.001）. Visible lumen diameter percentage also varied depending on the stent type. In comparison with the conventional coronary angiography

4 of 6 in-stent stenoses were correctly detected. The sensitivity and specificity for the detection of in-stent stenosis were 66.7% and 84.6%

respectively. Conclusions Using a 64-slice CT

the stent lumen is partly visible in most of the stents. And 64-slice CT may be useful in the assessment of stent patency.