Assessment of coronary stents by 64-slice computed tomography: in-stent lumen visibility and patency.
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.
Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China.
Ling-Yan
LY
Kong
Zheng-Yu
ZY
Jin
Shu-Yang
SY
Zhang
Zhu-Hua
ZH
Zhang
Yi-Ning
YN
Wang
Lan
L
Song
Xiao-Na
XN
Zhang
Yun-Qing
YQ
Zhang
D000328:Adult; D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000628:therapy*; D054855:Drug-Eluting Stents; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011857:Radiographic Image Interpretation, Computer-Assisted; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed