Delayed complications after flow-diverter stenting: Reactive in-stent stenosis and creeping stents

• Published in: Journal of clinical neuroscience 2014-07, Vol.21 (7), p.1116-1122
• Main Authors: Cohen, José E, Gomori, John Moshe, Moscovici, Samuel, Leker, Ronen R, Itshayek, Eyal
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Aneurysm - surgery; Brain aneurysm; Cerebral Angiography; Child; Complications; Constriction, Pathologic - etiology; Constriction, Pathologic - therapy; Embolization, Therapeutic - adverse effects; Female; Flow-diverter stent; Follow-Up Studies; Humans; In-stent stenosis; Male; Middle Aged; Neurology; Retrospective Studies; Stent migration; Stents - adverse effects; Treatment Outcome; Young Adult
• ISSN: 0967-5868; 1532-2653
• DOI: 10.1016/j.jocn.2013.11.010

Abstract We assessed the frequency and severity of changes in stent configuration and location after the treatment of intracranial aneurysms, and patterns of in-stent stenosis. We retrospectively reviewed data for consecutive aneurysm patients managed with endovascular implantation of flow-diverter stents (Silk Flow Diverter [Balt Extrusion, Montmorency, France] and Pipeline Embolization Device [ev3/Coviden, Minneapolis, MN, USA]) from October 2011 to July 2012. Routine 2, 6, 9–12, and 16–20 month follow-up angiograms were compared, with a focus on changes in stent configuration and location from immediately after deployment to angiographic follow-up, and the incidence and development of in-stent stenosis. Thirty-four patients with 42 aneurysms met inclusion criteria. The Silk device was implanted in 16 patients (47%, single device in 15), the Pipeline device in 18 (53%, single device in 16). On first follow-up angiography, in-stent stenosis was observed in 38% of Silk devices and 39% of Pipeline devices. In-stent stenosis was asymptomatic in 12 of 13 patients. One woman presented with transient ischemic attacks and required stent angioplasty due to end tapering and mild, diffuse in-stent stenosis. Configuration and location changes, including stent creeping and end tapering were seen in 2/16 patients (13%) with Silk devices, and 0/18 patients with Pipeline devices. We describe stent creeping and end tapering as unusual findings with the potential for delayed clinical complications. In-stent stenosis, with a unique behavior, is a frequent angiographic finding observed after flow-diverter stent implant. The stenosis is usually asymptomatic; however, close clinical and angiographic monitoring is mandatory for individualized management.