[Efficacy of experimental renal embolization with microspheres. Additionally, a critical report on the complication rate of intra-arterial embolization with particles (author's transl)].

Renal embolization was performed in 12 dogs using the Seldinger technique and microspheres 250 +/- 40 micrometer in diameter. Periodical arteriography, microangiographies and histological analysis was carried out to control the efficacy of embolization. As a result, renal arteries could be embolized wi. th microspheres, however, because of statistical distribution there were histologically anemic and normal parenchyma situated closely together. In more than 50% there was a reflux of microspheres which could only be detected by histological examination, while angiographies showed a totally normal vascular pattern. Microspheres should not be used in clinical embolization. Experimental investigation of embolization materials must almost embrace histological analysis.