NITINOL STENTS

DEPLOYED IN THE INTERNAL CAROTID ARTERIES; GEOMETRIC EFFECTS

Abstract

Stents deployed in the carotid arteries cause significant geometric changes in the vessels, influencing the flexibility and torsion characteristics of the vessels, which are aggravated by the high degree of mobility in this area of the body. The influence of these physical characteristics on carotid blood flow could influence the long term performance of the deployed stents. Objectives: To evaluate the geometric changes in the carotid arteries after deployment of self expanding nitinol stents. Settings: AFIC-NIHD. Period: November 2003 to August 2008. Material & methods: 45 cases of carotid artery stenting (CAS) done. We selected cases where the stenting to the internal carotid artery (ICA) had been done across the bifurcation of the common carotid artery (CCA) with self expanding nitinol stents, and when DICOM videos that had pre and post stenting images in the same imaging projection were available for analysis. Based on the inclusion criteria 21 videos were selected and deemed fit for taking measurements. The measurement system proposed by Berkefeld et al which involved the measurement of the CCA-ICA (common carotid artery –internal carotid artery) angle and ICA-offset was used. These variables were measured using onscreen measuring software which can measure linear distances and angles after appropriate calibration for each image. Results: We did not find any significant changes in the ICA-offset; significant changes in the CCA-ICA angle were noted.