Authors: David Maintz Harald Seifarth Rainer Raupach Thomas Flohr Michael Rink Torsten Sommer Murat Özgün Walter Heindel Roman Fischbach
Publish Date: 2005/12/07
Volume: 16, Issue: 4, Pages: 818-826
Abstract
The purpose of this study was to test a large sample of different coronary artery stents using four image reconstruction approaches with respect to lumen visualization lumen attenuation and image noise in 64slice multidetectorrow computed tomography MDCT in vitro and to provide a catalogue of currently used coronary artery stents when imaged with stateof theart MDCT We examined 68 different coronary artery stents 57 stainless steel four cobaltchromium one cobaltalloy two nitinol four tantalum in a coronary artery phantom vessel diameter 3 mm intravascular attenuation 250 HU extravascular density −70 Stents were imaged in axial orientation with standard parameters 32x06 collimation pitch 024 680 mAs 120 kV rotation time 037 s Four different image reconstructions were obtained with varying convolution kernels and section thicknesses 1 soft 06 mm 2 soft 075 3 medium soft 06 and 4 stentoptimized sharp 06 To evaluate visualization characteristics of of the stent the lumen diameter intraluminal density and noise were measured The highresolution kernel offered significantly better average lumen visualization 57 ±10 and more realistic lumen attenuation 222 HU ±66 HU at the expense of increased noise 153 HU ±37 HU compared with the soft and mediumsoft CT angiography CTA protocol p0001 for all Stents with a lumen visibility of more than 66 were Arthos pico Driver Flex Nexus2 S7 Tenax complete Vision all 67 Symbiot Teneo 70 and Radius 73 Only ten stents showed a lumen visibility of less than 50 Stent lumen visibility largely varies depending on the stent type Even with the improved spatial resolution of 64slice CT a stentoptimized kernel remains beneficial for stent visualization when compared with the standard mediumsoft CTA protocol Using 64slice CT and highresolution kernel the majority of stent products show a lumen visibility of more than 50 of the stent diameter
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