Evaluation and Management of In-stent Low-density Area on CTA after Carotid Artery Stenting at Subacute Phase

Abstract

Objective: We examined the prognosis and background factors associated with in-stent low-density areas (LDAs) on CTA in the subacute phase after carotid artery stenting (CAS). Materials and Methods:Among 175 lesions for which CAS was performed between April 2008 and September 2016, 100 lesions for which CTA were conducted in the subacute phase after CAS were included for retrospective analysis.Results: Low-density areas were observed in 36 (36.0%) of the 100 lesions. All patients received conservative medical treatment. There was no patient with new neurologic symptoms in the subacute phase. In most lesions, peak stenosis rate was observed relatively early, which gradually declined after 1 week. Low-density areas were observed and the stenosis rate was relatively high in all patients with plaque protrusion immediately after CAS. The use of open-cell stents significantly increased the formation of LDAs. Most LDAs were consistent at the level of the previous most stenotic sites. Conclusion:Low-density areas in the subacute phase after CAS were relatively frequent. In this study, the course was asymptomatic in all patients, and remission was gradually achieved. However, LDAs may have been associated with serious ischemic complications in the subacute phase, as reported in the literature. Therefore, medical treatment, involving intensive antithrombotic therapy, and careful follow-up should be considered.