Time versus density enhancement of liver, spleen, and great vessels following rapid intravenous infusion of perflubron emulsion

Abstract

We studied hepatosplenic enhancement in rhesus monkeys for 5 hr after rapid administration of perflubron (perfluorooctyl bromide [PFOB]) in an attempt to determine a clinically useful imaging window. Five rhesus monkeys were examined using perflubron emulsion, 90% w/v perfluorochemical administered intravenously at a dose of 1.5 ml/kg and rate of 0.5 ml/sec. Helical computed tomography examination of the abdomen was obtained prior to the contrast bolus and 5 min, 30 min, 1, 2, 3, 4, and 5 hr postcontrast. Mean density of liver, spleen, and aorta was measured at each time interval. Significant aortic enhancement of 53 +/- 7 Hounsfield units (HU) (p < .0001) and liver enhancement of 19 +/- 4 H (p < .0004) occurred after 5 min and did not change significantly (p > .05) over 5 hr. Splenic enhancement of 35 +/- 9 HU was significant at 5 min (p < .0001) and continued to increase for 5 hr. Enhancement of the liver, blood vessels, and spleen is rapid and persists for at least 5 hr, which suggests a wider temporal window for hepatosplenic imaging with perflubron than is currently available with iodinated contrast agents.