Use of Perfluorooctylbromide (PFOB) to Detect Liver Abscesses with Computed Tomography

Abstract

Although perfluorooctylbromide (PFOB) is known to stimulate macrophages, particulates given intravenously (IV) can inhibit the body's response to infection by blocking the reticuloendothelial system. Since PFOB enhances abscesses on computed tomography (CT), the authors evaluated its safety and efficacy by assessing the mortality and abscess volume in 104 rabbits with intrahepatic abscesses given either PFOB or lactated Ringer's (LR), and by comparing its efficacy to that of 76% meglumine sodium diatrizoate (MSD76). Abscesses were produced by injecting a virulent strain of E. coli into the liver. Two days later, five of the rabbits had died. Of the remaining rabbits, 50 were given 5 g/kg PFOB IV, and 49 were given an equal volume of LR. All rabbits had a CT scan at four and at ten days after infusion. They were killed before the second CT scan. Thirty seconds before being killed, 28 rabbits given LR were given a bolus of 2 ml/kg MSD76 IV. Following CT, rabbits were frozen, sliced, and photographed. Abscess volumes were calculated by digitizing the photographs of the anatomic sections and the CT images. MSD76 enhanced the liver by 105 Hounsfield units (HU) more than the liquefied abscess center. The abscess wall enhanced to the same degree as liver, resulting in nonvisualization of three of six abscesses less than 3 mm in size, and a 30% underestimation of true abscess volume.(ABSTRACT TRUNCATED AT 250 WORDS)