TIME VERSUS DENSITY ENHANCEMENT OF LIVER, SPLEEN, AND GREAT-VESSELS FOLLOWING RAPID INTRAVENOUS-INFUSION OF PERFLUBRON EMULSION

Rationale and Objectives. We studied hepatosplenic enhancement in rhes us monkeys for 5 hr after rapid administration of perflubron (perfluor ooctyl bromide [PFOB]) in an attempt to determine a clinically useful imaging window. Methods. Five rhesus monkeys were examined using perfl ubron emulsion, 90% w/v perfluorochemical administered intravenously a t a dose of 1.5 ml/kg and rate of 0.5 ml/sec. Helical computed tomogra phy examination of the abdomen was obtained prior to the contrast bolu s and 5 min, 30 min, 1, 2, 3, 4, and 5 hr postcontrast, Mean density o f liver, spleen, and aorta was measured at each time interval. Results . Significant aortic enhancement of 53 +/- 7 Hounsfield units (HU) (p < .0001) and liver enhancement of 19 +/- 4 H (p < .0004) occurred afte r 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 co ntinued to increase for 5 hr. Conclusion. Enhancement of the liver, bl ood vessels, and spleen is rapid and persists for at least 5 hr, which suggests a wider temporal window for hepatosplenic imaging with perfl ubron than is currently available with iodinated contrast agents.