The use of imagent^R bp in diagnostic imaging research and ₁₉f magnetic resonance for Po² measurements

Imagent BP (90% w/v perflubron emulsion) is radiopaque and serves as an X-ray contrast medium. Quantitative X-ray Computed Tomography, provides the means to noninvasively estimate tissue perflubron concentration providing three unique capabilities: 1) The use of the same animal for biodistribution and elimination analysis; 2) The precise geographic distribution of the agent to more accurately quantitate localized accumulations; and 3) The ability to gather physiologic data by monitoring the time dependent distribution of perflubron. It is known that the Tl-1 of “F of perfluorochemicals is linearly related to the dissolved oxygen which allows the quantitation of PO2 in-vivo. We showed using perflubron in phanta that not only was Tl”1 linearly related to PO2 but also T2'1 and both were insensitive to perflubron concentration. Since flow interferes with signal, the first in-vivo experiments have focused on stationary perflubron located within phagocytes. Tl'1 measured from this environment suggested a PO2 of 15-25 Torr. Tl”1 increased by nearly 50% when the FIO2 was increased from 20 to 100% reflecting an increase in intracellular PO2 on the order of 25 Torr.