PERFLUOROCARBON-ENHANCED SONOGRAPHY - VALUE IN DETECTING ACUTE VENOUSTHROMBOSIS IN RABBITS

OBJECTIVE. We have previously shown that perfluorocarbon emulsions adm inistered IV act as contrast material during sonography by creating mo ving echoes in veins. Accordingly, we performed a study on rabbits des igned to establish the value of perfluorocarbon-enhanced sonography in detecting acute venous thrombi.MATERIALS AND METHODS. Constriction of the inferior vena cava (IVC) just above the renal veins was establish ed surgically in 15 rabbits. Thrombus was induced in the IVC in 10 of these; the other five served as controls. Gray-scale and color Doppler sonography were performed before and after the IV infusion of 3 ml/kg of perflubron emulsion (formulation AF0102, Alliance Pharmaceutical, San Diego, CA). Sonograms were evaluated for the presence and extent o f thrombus. Three additional rabbits with percutaneously induced IVC t hrombosis were studied before and after the IV administration of 0.2 m l of a preparation of microbubbles of perfluorocarbon gas (formulation PRD002, Alliance Pharmaceutical). In these animals thrombi were confi rmed at autopsy. RESULTS. Unenhanced sonograms allowed detection of th rombi in the IVC in nine of the 10 animals with surgically induced thr ombus but were inaccurate in determining clot extent. Filling the lume n of the IVC with moving echoes created by administration of perflubro n emulsion allowed more complete delineation of the size and extent of thrombus and permitted detection of residual venous flow not observed on unenhanced scans. The perfluorocarbon gas microbubbles provided si milar benefits. CONCLUSION. Our results show that IV administration of perflubron emulsion or perfluorocarbon gas microbubbles improves imag ing of veins on sonography and may aid in the assessment of thrombi.