BACKGROUND: To evaluate the characteristics and the effects of an embolic agent, available commercially, consisting of irregular - Polyvinyl Alcohol (PVA), and to compare with a spherical agent, of brazilian technology, consisting of Polyvinyl Alcohol and Polyvinyl Acetate (PVA + PVAc). METHODS: Renal arterial embolization was performed in females of New Zealand White rabbits. Irregular - PVA was used in 24 animals. Spherical - PVA+PVAc was used in 24 animals. Six animals were used as control. All animals were maintained in captivity until the euthanasia, after 48 hours, 5 days, 10 days and 30 days. RESULTS: Both agents resulted in vessel occlusion and organ infarction. The initial macroscopic study of the arteries embolized with irregular-PVA, the occluding plug consisted of thrombus and PVA. In vessels embolized with spherical-PVA+PVAc, the occluding plug consisted mostly of the embolic agent. After 30 days, there is absorption of the thrombus and retraction of the agents of PVA-irregular, creating spaces. With spherical-PVA+PVAc, it can be observed the agents surrounded by intense fibrosis. CONCLUSION: Both particles were effective to cause tissue ischemia. The inflammatory reaction was more intense with spherical-PVA+PVAc, besides presenting larger degree of penetration in the vascular system.
Animal experimentation; Embolization, therapeutic; Polyvinyl alcohol; Radiology; interventional
