Article Figures & Data
Figures
- FIG 1.
The relationship between FD design parameters and resulting performance characteristics. Green and red arrows indicate a beneficial or detrimental relationship, respectively, in terms of device performance and safety. Black horizontal arrows indicate either an independent or multifactorial relationship between the design parameters and performance characteristics. A, Improved opening force assumes that the wires within the braid do not plastically deform after being crimped in their microcatheters, allowing complete device re-expansion. B, Wall apposition is complex and depends on many variables, including the tortuosity of the parent vessel.
- FIG 2.
Illustration of the relationship between the braid angle (defined by the red theta) and the number of wires or PPI and pore density. This figure was made with BioRender (https://www.biorender.com/).
Tables
Primary FD Materials Alloy Elastic Modulus Elastic Limit Market-Approved FD Examples Cobalt-nickel-chromium ∼120–240 GPaa ∼ 0.5 to 1.5%a PED, PED Flex, PED Shield, PED Vantage, Surpass Streamline (Stryker), Surpass Evolve2 Nitinol ∼ 40–10 GPaa ∼ 6%–12%a FRED, FRED Jr, FRED X, Silk, Silk+, p64, Tubridge2 ↵a Use due consideration in applying values for modeling because the Young modulus and elastic limit (pseudoelastic for nitinol) can vary widely due to process-structure texture and strength outcomes. Bookends given here are realistic possible outcomes dependent on the supplier production path and target outcomes.
Radiopaque Materials Alloy Radiopacity (Density)a Market-Approved FD Examples Radiopaque Element Type Platinum-tungsten ∼19.75 g/cm3 PED, PED Flex, PED Shield, Surpass Streamline, Surpass Evolve 12 Platinum-tungsten wires incorporated into the overall braid2 Tantalum 16.65 g/cm3 FRED, FRED Jr, FRED X Interwoven tantalum strands between braided layers and 4 markers on flared ends of device2 Platinum 21.45 g/cm3 Silk, Silk+, p64, Tubridge Silk features 4 platinum wire strands with flared ends. Silk+ features 8 platinum wires and 4 platinum coils at device ends.2 The p64 features 2 platinum wires wrapped along the length of the device and 8 markers at the device end.36 Tubridge features 2 platinum strands2 Nitinol outer, platinum inner DFT ∼6 g/cm3 for nitinol; 21.45 g/cm3 for platinum Silk Vista, Silk Vista Baby, p48MW (phenox), p48_HPC, DERIVO 48 Braided DFT wires. DERIVO features 3 additional markers on the device end2 Cobalt-nickel-chromium outer, platinum inner DFT ∼8.5 g/cm3 for cobalt-nickel-chromium; 21.45 g/cm3 for platinum Pipeline Vantage 48 or 64 Braided DFT wires14 a Density is given as a rough proxy for radiopacity in lieu of the lack of corroborative data for these materials and geometries by a consistent approach. Future studies, outside the present scope, may focus on quantitative radiopacity comparison as a function of material, geometry, filtering materials, and imaging parameters. Such a study could be used to aid in the design of future devices.
