Alteration in starch microsphere degradation following contrast angiography in the dog kidney

Six adult mongrel dogs received bilateral sequential renal arterial injections of degradable starch microspheres following preadministration arteriograms. Renal arterial flow was measured using electromagnetic flow probes, and microspheres were administered until flow was blocked completely. One kidney in each dog was subjected to immediate postembolization arteriography, while the contralateral kidney served as a control. In the control kidneys, arterial flow returned to 90-95% of baseline within 30 minutes of embolization, and angiography at this time revealed a normal nephrogram. Blood flow in the kidneys that received postembolization arteriography returned to only 60-65% of baseline, even when followed up to 1 hour. Angiography at this time revealed persistent defects in the nephrogram. The effect of heparin, Renografin-60, and distilled deionized water on amylase activity was evaluated in vitro. No change in enzyme activity was noted.