A new embolization agent: Embolization of the kidneys with ethylene glycol dimethacrylate-hydroxyethyl methacrylate copolymer microbeads

Ethylene glycol dimethacrylate (EGDMA)-hydroxyethyl methacrylate (HEMA) copolymer microbeads (125-150 mum in diameter) were produced by suspension polymerization. The percent of HEMA incorporated and the swelling ratio of the non-porous microbeads produced were 12% and 22.7%, respectively. Microbeads, sterilized with ethylene oxide, were used in the embolization of the kidneys of three adult mongrel dogs by angiography. The effectiveness of the embolization was examined by angiographs after each step. In the first step of the embolization, the microbeads reached the pre-capillaries and blood flow was successfully blocked, which was confirmed by accumulation of the contrast agent within the kidneys. In angiograms after another injection, as the second step, again there were neither contrast agent movement toward the kidneys nor distribution through the paranchyme. The embolized kidneys were subjected to histopathologic examinations where pathological changes were observed.