Mobility of an in-stent plaque protrusion detected with carotid duplex during the carotid artery stenting procedure: a case report.

In-stent plaque protrusion (ISP) is a predictor for ischemic complications in carotid artery stenting (CAS). Because its mobility would further increase the distal embolization risk, the intraprocedural detection of mobility is important but has not yet been reported. We present an 87-year-old male with symptomatic right carotid artery stenosis who underwent CAS. Intravascular ultrasound (IVUS) after stent deployment revealed a small ISP, and simultaneous extravascular carotid duplex disclosed its mobility. After coverage of the ISP with stent-in-stent implantation, no remaining protrusion was observed with either IVUS or carotid duplex. The patient experienced no periprocedural strokes. Carotid duplex is suited to evaluate targets' movement because of its excellent temporal resolution. Carotid duplex has potential value for intraprocedural risk estimation of ISP.