Background. Micro-computed tomography (microCT) is an important tool for preclinical vascular imaging, with micron-level resolution. This non-destructive means of imaging allows for rapid collection of 2D and 3D reconstructions to visualize specimens prior to destructive analysis such as pathological analysis.
Objective. The aim of this study was to suggest a method for ex vivo, postmortem examination of stented arterial segments with microCT. And ex vivo evaluation of alpha lipoic acid (ALA) coated stent on restenosis in rabbit model.
Methods. The BMS (3.0 mm × 18 mm, Co-Cr alloy) and the ALA coated stent were implanted in the left or right iliac arteries alternatively in eight New Zealand white rabbits. Paclitaxel and sirolimus-eluting stent were employed as a positive control. After 28 day post-implantation, the part of iliac arteries surrounding the stent were removed carefully and processed for microCT. All samples were subjected to an X-ray source operating at 50 kV and 200 μA with an exposure time of 1.2 sec and by using a 3D isotropic resolution (pixel size) of 17.09 ㎛. The region of interest was traced and measured by CTAN analytical software.
Results. As a result, the difference of lengths and volumes between expanded stents, which may relate to injury score in pathological analysis, was not significance. Though it was not statistically significant, it showed that the extent of neointema of mid-region of stents was relatively higher than that of anterior and posterior region as showing cross-sectional 2-D image in parts of stents. Restenosis rate of ALA coated stent was higher (30.7%) than that of paclitaxel-eluting stent (32.6%), but lower than that of BMS (37.8%) and sirolimus-eluting stent (26.4%).
Conclusion. MicroCT enables the non-constructive postmortem analysis of stented arteries. Coating of ALA showed inhibitory effect on stent restenosis as comparing commercial drug-eluting stent. These results suggest that MicroCT can be use an accessorial tool for pathological analysis.
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