title: Preparation, characterization, and evaluation of radiopaque hydrogel filaments for endovascular embolization.
abstract: Radiopaque hydrogel filaments were prepared, characterized, and evaluated for potential use as implants for endovascular embolization of vascular defects. Three hydrogel formulations were prepared by free radical polymerization: (i) poly(ethylene glycol) diacrylate with 2,4,6-triiodophenyl penta-4-enoate (PEG-I), (ii) poly(ethylene glycol) diacrylamide with barium sulfate (PEG-B), and (iii) poly(propylene glycol) diacrylate with barium sulfate (PPG-B). The PEG-B and PPG-B hydrogels exhibited radiopacity comparable with clinically used platinum coils, whereas the PEG-I hydrogel did not. In the dry state, the average ultimate tensile strength and strain of the hydrogels ranged from 37 to 128 gf and 21% to 72%, respectively. The PEG-B hydrogel had significantly higher tensile strength compared with the PEG-I hydrogel. In the hydrated state, the average ultimate tensile strength and strain ranged from 5 to 15 gf and 7% to 30%, respectively. Statistically significant differences in tensile strength were not present when hydrated. Compared with poly(ethylene) after 4-week implantation into the subcutaneous space of rabbits, the PEG-I hydrogel elicited slightly more inflammation, whereas the PEG-B and PPG-B hydrogels elicited less inflammation. All three hydrogel formulations elicited less fibrous encapsulation than poly(ethylene). With further development, these materials have potential as embolization devices.
authors.affiliation: MicroVention Terumo, Aliso Viejo, California 92656.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Constant
authors.affiliation: MicroVention Terumo, Aliso Viejo, California 92656.
authors.forename: Edward M
authors.initials: EM
authors.lastname: Keeley
authors.affiliation: MicroVention Terumo, Aliso Viejo, California 92656.
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Cruise
mesh_terms: D000178:Acrylamides / Q000737:chemistry; D000179:Acrylates / Q000737:chemistry; D000818:Animals; D001466:Barium Sulfate / Q000737:chemistry; D001672:Biocompatible Materials / Q000737:chemistry*; D004621:Embolization, Therapeutic / Q000295:instrumentation*; D015743:Giant Cells, Foreign-Body / Q000276:immunology / Q000473:pathology; D006801:Humans; D020100:Hydrogels / Q000737:chemistry*; D008422:Materials Testing; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D011409:Propylene Glycols / Q000737:chemistry; D011817:Rabbits; D013718:Tensile Strength
chemical_list: D000178:Acrylamides; D000179:Acrylates; D001672:Biocompatible Materials; D020100:Hydrogels; D011108:Polymers; D011409:Propylene Glycols; C012504:polypropylene glycol; D001466:Barium Sulfate; D011092:Polyethylene Glycols