The experimental study of EVAL (a non-adhesive fluid embolism material made in China)in embolization of cerebral arteriovenous malformations

Objective Study the physiochemieal characteristics of ethylene vinyl alcohol copolymer (EVAL)mixtures(a non-adhesive fluid embolism matedal made in China)in vitro to determine the feasibility of the mixtures in endbolization of cerebral arteriovenous malformations.Methods In various EVOH)were assayed by the rotational viscosimeter.The EVAL solutions of various concentrations(contain 6%and 8%EVOH)were pushed out slowly under 1cm of physiological saline liquid level to assay the precipitation times.With the electronic microscope.the uhm-structure of EVAL solid in vitro was observed.Results The visoosities of different mixtures difiered significantly.Along with the increase of EVAL concentrations,the viscosity also raised.The temperature of different mixtures differed signiticanfly.Along with increase of EVAL temperature,the viscosity decreased.The precipitation times were not affected signifieandy by the concentration and tempergture,The EVAL solutions might precipitate in vitro and become solid.With the low power electronic microscope,the EVAL solid Was found to like sponge,and with the high power electronic microscope,the EVAL solid was found to like a laminar structure with many meshes.Conclusions Because of their different physiochemical properties,the various EVAL mixtures are suitable for the embolization of difierent types of cerebral arteriovenous malformations. Key words: Non-adhesive fluid embolism material;  EVAL; Physiochemical property; Cerebral arteriovenous malformation