John Moshe Gomori MD, Presenter: Consultant, Medymatch Technology Ltd

Jose Enrique Cohen MD, Abstract Co-Author: Nothing to Disclose

Assess the frequency and severity of changes in stent configuration and location, and patterns of in-stent stenosis of flow diverter stents.

: Retrospective review of consecutive data from October 2011 to July 2012 of Silk flow diverter [Balt Extrusion, Montmorency, France] and Pipeline embolization device [ev3/Coviden, Minneapolis, MN, USA]. Routine 2, 6, 9–12, and 16–20 month follow-up angiograms were compared, with a focus on changes between stent configuration and location immediately after deployment and on 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 12/13 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 such as 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 among the unusual findings with 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. Stent creeping and end tapering is more common with Silk devices.

Silk diverter stents are less stable than Pipeline devices. Both devices show instent stenosis and need careful monitoring. 

Gomori, J, Cohen, J, Delayed Complications after Flow-diverter Stenting: Reactive In-stent Stenosis and Creeping Stents  .  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14008795.html