Introduction: Flow-diverting stents (FDS) are braided, self-expanding stents designed for the treatment of intra-cranial aneurysms. Their unique properties may also make them well suited for treating extra-cranial carotid artery dissections with high-grade stenosis. Here we report our experience treating two patients with the Pipeline Embolization Device (PED) in addition to a literature review focused on indications, clinical results, and complications.
Methods: Two patients with symptomatic, medically refractory, extra-cranial carotid artery dissections underwent treatment with overlapping PEDs. A PUBMED search identified four articles reporting treatment of extra-cranial carotid dissections with FDS. Our analysis is restricted to those with high-grade stenosis.
Results: Case 1) 58yM on Plavix for stroke presents with new thromboembolic strokes downstream of a L ICA chronic dissection with high-grade stenosis and pseudoaneurysm formation. The dissection and pseudoaneurysm were successfully treated in a two-stage procedure with overlapping PEDs and a proximal TCS. Case 2) 59yM presents with spontaneous left petrous-carotid dissection with severe stenosis, and recurrent thromboembolic strokes despite maximal medical therapy. The dissection was successfully treated with overlapping PEDs. A proximal TCS was used to repair an iatrogenic carotid dissection. At 6-month follow-up, both patients are without recurrent events. Review of the literature reveals 13 additional patients with 14 high-cervical carotid dissections and high-grade stenosis successfully treated with PEDs. Complications included iatrogenic dissection, delayed in-stent-thrombosis, and PED collapse.
Conclusions: FDS treatment of extra-cranial carotid artery dissections with high-grade stenosis demonstrates high technical success and good intermediate results. TCS are stiff, large-system stents not well suited for the angulation of the high-cervical ICA. Classical intracranial stents are only available up to 4.5-mm in size and therefore may be too small for this ICA segment. PEDs are extremely navigable and available in a 5.0-mm size (expanding up to 5.25-mm). Their low porosity decreases thromboembolic risk by trapping friable debris and promotes thrombosis of pseudoaneurysms.
Patient Care: Our two cases of symptomatic, medically refractory extra-cranial carotid artery dissections with associated high-grade stenosis treated with PEDs add to a growing body of literature describing the indications, outcomes, and complications associated with off-label use of flow diverting stents which will serve to guide physicians in making appropriate patient specific treatment decisions.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) compare and contrast the characteristics of traditional carotid stents, classical intracranial stents, and flow-diverting stents; 2) describe the relative indications and efficacy for treatment of carotid artery dissection with a flow-diverter stent; 3) discuss the complications associated with flow-diverter stenting in the context of extra-cranial carotid dissections
References: 1. Cohen JE, Gomori JM, Rajz G, Itshayek E, Eichel R, Leker RR (2015) Urgent off-label use of the pipeline flow diverter stent in selected ischemic cerebrovascular conditions: thrombotic segments and tortuous arteries. J Neurointerv Surg 7(9):671-5
2. Brzezicki G, Rivet DJ, Reavey-Cantwell J (2015) Pipeline Embolization Device for treatment of high cervical and skull base carotid artery dissections: clinical case series. J Neurointerv Surg 0:1-7.
3. Vega RA, Brzezicki G, Reavey-Cantwell JF (2015) Delayed collapse of a Pipeline Embolization Device. Operative Neurosurgery 0(0):1-6.
4. Cohen JE, Gomori JM, Ben-Hur T, Moscovici S, Itschayek E (2012) The use of telescoped flow diverters as an endovascular bypass in the management of symptomatic chronic carotid occlusion. J Clin Neurosci 19(7):1026-8