In-vivo-vermessung koronarer stents in ganzen gefäßsegmenten mittels dreidimensionaler intravaskulärer ultraschallanalysen: Eine Übersicht

The implantation of metallic endoprostheses (i. e., stents) is a rapidly expanding interventional technique for the catheter-based therapy of symptomatic patients with significant coronary stenoses. But stents are frequently radiolucent and after deployment difficult to appreciate on fluoroscopy and coronary angiograms obtained by x-ray. Intravascular ultrasound (IVUS), on the other hand, permits detailed examination of coronary stent apposition and expansion in vivo. Recently, automated systems for three-dimensional (3-D) reconstruction and analysis of IVUS images have been developed. The initial experience with 3-D IVUS in coronary stenting is positive. Different technical approaches demonstrated superiority of 3-D IVUS in detecting both, the site of the smallest in-stent lumen cross-sectional area and sub-optimal results following stent deployment. In-addition, the restenosis process inside stents can excellently be studied with IVUS. In-stent neointimal ingrowth can be exmined with a computerized 3-D contour detection system that permits off-line detection of the neointimal leading edge and the coronary stent struts. This 3-D approach provides computerized measurement of neointimal volume, based on a large number of IVUS images. Considering the current trend towards more complex coronary stenting procedures, a feasible and reliable 3-D analysis tool for clinical on-line assessment after stent deployment may also be very useful.