An arteriovenous malformation model with a transparent nidus was constructed to investigate the embolization behavior of polyvinyl acetate (PVAc) solution relative to flow velocity in the feeding artery and injection speed. It was found that the liquid embolic material flowed distally when injected too fast or when the flow velocity was too low. In addition, we found that solution consisting of PVAc plus metrizamide was a better embolic material than solution containing only PVAc.