64-slice computed tomography assessment of coronary artery stents: a phantom study.
OBJECTIVE
To compare the use of a new 64-slice computed tomography (CT) scanner with 16-slice CT in the visualization of coronary artery stent lumen.


METHODS
Eight different coronary artery stents, each with a diameter of 3 mm, were placed in a static chest phantom. The phantom was positioned in the CT gantry at an angle of 0 degrees and 45 degrees towards the z-axis and examined with both a 64-slice and a 16-slice CT scanner. Effective slice thickness was 0.6 mm with 64-slice CT and 1 mm with 16-slice CT. A reconstruction increment of 0.3 mm was applied in both scanners. Image quality was assessed visually using a 5-point grading scale. Stent diameters were measured and compared using paired Wilcoxon tests.


RESULTS
Artificial lumen reduction was significantly less with 64-slice than with 16-slice CT. Average visible stent lumen was 53.4% using 64-slice CT and 47.5% with 16-slice MSCT. Most severe artifacts were seen in stents with radiopaque markers. Using 64-slice CT, image noise increased by approximately 30% due to thinner slice thickness.


CONCLUSIONS
Improved spatial resolution of 64-slice CT resulted in superior assessment of coronary artery stent lumen compared to 16-slice CT. However, a relevant part of the stent lumen is still not assessable with multi-slice CT.
Department of Diagnostic Radiology, Aachen University of Technology, Germany. mahnken@rad.rwth-aachen.de
A H
AH
Mahnken
G
G
Mühlenbruch
T
T
Seyfarth
T
T
Flohr
S
S
Stanzel
J E
JE
Wildberger
R W
RW
Günther
A
A
Kuettner
D016477:Artifacts; D017023:Coronary Angiography / Q000295:instrumentation* / Q000379:methods*; D023921:Coronary Stenosis / Q000175:diagnosis; D006083:Graft Occlusion, Vascular / Q000175:diagnosis; D015588:Observer Variation; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D015607:Stents; D014057:Tomography, X-Ray Computed / Q000295:instrumentation* / Q000379:methods*