Changes of high-resolution magnetic resonance imaging before and after Wingspan stent in patients with intracranial large artery stenosis / 中国脑血管病杂志

ABSTRACT

Objective To evaluate the imaging changes of the arterial wall and lumen at the site of intracranial large artery lesions with high-resolution magnetic resonance imaging (HR-MRI) before and after Wingspan stent implantation.Methods From December 2013 to December 2014,9 patients with symptomatic intracranial arterial stenosis (stenosis rate70%-99%) admitted to the Department of Interventional Neuroradiology,Xuanwu Hospital,Capital Medical University were enrolled retrospectively.The sites of the lesions included middle cerebral arteries,basilar artery,and intracranial segment of vertebral artery.Head 3D HR-MRI technique was used to analyze and compare the changes of the tube-wall enhancement areas in the lesion sites through image registration and matching.The consistency of stenosis rates measured by HR-MRI and DSA was compared through Pearson correlation analysis and Bland-Altman Plot.Results The success rate of technique was 100% without related complications.(1) After Wingspan stent implantation,the gadolinium enhancement in the vascular walls of the stenosis sites was decreased significantly compared with that before procedure.The area of enhancement decreased was 87±16% after stent implantation compared with before implantation,and the difference was statistically significant (t=2.325,P=0.049).(2) Before stent implantation,the mean stenosis rates of the HR-MRI and DSA measurements were 82±6% and 82±8% respectively,and the difference was not statistically significant (t=0.051,P=0.961);after procedure,the mean stenosis rates of HR-MRI and DSA measurements were 16±12% and 21±12% respectively,and the difference was not statistically significant (t=1.345,P=0.216).(3) The Pearson correlation coefficients of HR-MRI and DSA for stenosis rate measurement before and after stent implantation were 0.347 (P=0.361) and 0.545 (P=0.129) respectively.Bland-Altman statistical images showed that most of the data points were within the consistency limit (x-±1.96 s).Conclusions As an in vivo noninvasive imaging means,HR-MRI can be used to assess the changes of vascular walls of the lesion sites,the vascular lumen,and the original plaques after the intracranial stent release.It can also be used to evaluate the reconstruction of intracranial arterial walls.