The Silk flow-diverter stent for endovascular treatment of intracranial aneurysms

Abstract

Flow diverter (FD) stents represent a new endovascular technique developed for the treatment of complex intracranial aneurysms (wide neck, fusiform, large, and giant aneurysms) that are challenging for classic endovascular techniques such as coiling, balloon-assisted coiling and stent-assisted coiling. Low porosity, high metal coverage, and high pore density are the main properties of FD stents. These properties induce hemodynamic changes redirecting the blood flow away from the aneurysm and into the parent artery leading to gradual thrombosis of the aneurysm. FD stents also provide scaffolding for subsequent neoendothelial proliferation, and vessel wall remodeling. This is considered as a paradigm shift compared to prior endovascular methods, which predominantly aimed at providing treatment inside the aneurysmal sac. This paper describes in detail the first released FD stent, the Silk flow-diverter stent (Balt Extrusion, Montmorency, France), its mechanism of action and deployment technique. It reviews the pertinent literature regarding safety, efficacy and potential risks and complications associated with the use of this stent.

Keywords:

• endovascular treatment
• flow diversion
• intracranial aneurysms
• Silk flow diverter

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Endovascular treatment is the first-intention treatment for both ruptured and unruptured intracranial aneurysms.

• Large, giant, and fusiform aneurysms are challenging for both surgery and classic endovascular treatment, with low aneurysm occlusion rate and relatively high morbidity and mortality rates.

• Flow diversion is a new endovascular technique for aneurysm treatment. Flow diverter stents aim to reduce blood flow inside the aneurysm leading to gradual intra-aneurysmal flow stagnation, thrombosis, and subsequent remodeling of the parent vessel with regression of the aneurysm itself.

• Despite potential complications and limitations associated with flow diverter stents, they represent a paradigm shift in treatment of complex aneurysms for which no optimal alternative treatment exists.