Experimental study and clinical use of poly(vinyl acetate) emulsion as liquid embolisation material

Abstract

A new material, an emulsion of poly(vinyl acetate) was experimentally developed and clinically used to overcome several disadvantages in currently used liquid embolisation materials. The emulsion microparticles, 0.3-0.7 microns in size, possessed cationic charge on the surface and hence aggregated immediately on contact with fluids containing anions. This inert polymer has the advantage that it does not induce a deleterious reaction in living tissue. Moreover, its medium is water and it is not adhesive, like the cyanoacrylates. Several concentrations of emulsion were injected into the renal arteries of dogs. For the investigation of tissue reactions and the possibility of recanalisation, the emulsion was injected into rats both subcutaneously and into the renal arteries. The renal artery injections in dogs showed adequate radiopacity and consistent complete occlusion. The lower the concentration of the emulsion, the smaller the arteries which could be occluded. Even at very low concentrations, however, venous occlusion did not occur. Histological study of the embolised rat kidney revealed no detectable damage in the vessel wall and no recanalisation for up to 6 months. The subcutaneously injected PVAc emulsion elicited mononuclear cell infiltration and gradual centripetal fibrosis, without any deleterious effect on the surrounding tissue. A cerebral arteriovenous malformation (AVM) was embolised using the material. Histology of the resected nidus showed findings similar to those in the animal experiments.

Composite poly(vinyl alcohol)/poly(vinyl acetate) electrospun nanofibrous mats as a novel wound dressing matrix for controlled release of drugs

“…Also it was shown that PVAc remained inert in blood vessels. 34 Several patents are registered for novel compositions suitable for use in embolizing blood vessels using biocompatible polymers including PVAc. The composition of these inventions are particularly useful in embolizing blood vessels 35 or they can be applied to intravascular medical devices.…”

Renal Artery Embolization Using a New Liquid Embolic Material Obtained by Partial Hydrolysis of Polyvinyl Acetate (Embol): Initial Experience in Six Patients

“…In addition, newer embolic materials are still being developed and tested (3, 4, 13-16). Embolic materials used in renal vascular lesions include absolute ethanol, ethibloc, gelfoam, polyvinyl alcohol, isobutyl-2-cyanoacrylate, coils, detachable balloons and autologous tissues.…”

Laser-treated electrospun fibers loaded with nano-hydroxyapatite for bone tissue engineering

“…The hydrogels containing functional groups such as COOH usually show good biocompatibility with blood, body fluids, and tissues (Ha et al, 2013). This inert polymer has the advantage that it does not induce a deleterious reaction in living tissue (Sadato et al, 1994). Because of all these characteristics PVAc has been used in many medical fields, including drug and cell carries and in tissue engineering (Abdal-hay et al, 2015).…”