Flared non-flow diverting ends of the FRED flow diverter for cerebral aneurysms facilitate device anchoring at the arterial bifurcation

Introduction The Flow Redirection Intraluminal Device (FRED) flow diverter has a unique bilayer design, with the outer scaffolding stent extending beyond the inner flow diverting component by about 3 mm at each end. Here, we describe a technique to utilize these unrestrained flared ends for precise flow diverter placement in cases where the aneurysm and an adjacent branch are in close proximity and branch jailing is not desired, such as in posterior communicating artery aneurysms. Technical note: The distal end of the FRED device is pushed out of the microcatheter at the carotid terminus. Once the distal flared ends are fully open and well situated in the terminus, ideally with at least one of the limbs in the A1 segment of the anterior cerebral artery, the device is unsheathed under gentle forward pressure. This technique stabilizes the device at the distal landing zone and prevents unintended foreshortening at the distal end. This is particularly important for aneurysms located adjacent to the carotid terminus in order to assure adequate neck coverage, as well as avoiding jailing one of the branching parent arteries. An illustrative case is provided. Conclusions The non-flow diverting unrestrained flared ends of the FRED stabilize the distal end of the device when deployed directly into the branches at the arterial bifurcation. The technique is useful to provide adequate neck coverage of cerebral aneurysm located directly adjacent to the bifurcation as is frequently the case with posterior communicating artery aneurysms.

Hemodynamic Effects on Particle Targeting in the Arterial Bifurcation for Different Magnet Positions

The present study investigated the possibilities and feasibility of drug targeting for an arterial bifurcation lesion to influence the host healing response. A micrometer sized iron particle was used only to model the magnetic carrier in the experimental investigation (not intended for clinical use), to demonstrate the feasibility of the particle targeting at the lesion site and facilitate the new experimental investigations using coated superparamagnetic iron oxide nanoparticles. Magnetic fields were generated by a single permanent external magnet (ferrite magnet). Artery bifurcation exerts severe impacts on drug distribution, both in the main vessel and the branches, practically inducing an uneven drug concentration distribution in the bifurcation lesion area. There are permanently positioned magnets in the vicinity of the bifurcation near the diseased area. The generated magnetic field induced deviation of the injected ferromagnetic particles and were captured onto the vessel wall of the test section. To increase the particle accumulation in the targeted region and consequently avoid the polypharmacology (interaction of the injected drug particles with multiple target sites), it is critical to understand flow hemodynamics and the correlation between flow structure, magnetic field gradient, and spatial position.