Molecular Optical Imaging with Radioactive Probes

Background: Optical imaging (OI) techniques such as bioluminescence and fluorescence imaging have been widely used to track diseases in a non-invasive manner within living subjects. These techniques generally require bioluminescent and fluorescent probes. Here we demonstrate the feasibility of using radioactive probes for in vivo molecular OI. Methodology/ Principal Findings: By taking the advantages of low energy window of light (1.2-3.1 eV, 400-1000 nm) resulting from radiation, radionuclides that emit charged particles such as b + and b 2 can be successfully imaged with an OI instrument. In vivo optical images can be obtained for several radioactive probes including 2-deoxy-2-[F-18] fluoro-D-glucose ([F-18] FDG), Na F-18, (NaI)-I-131, (YCI3)-Y-90 and a Y-90 labeled peptide that specifically target tumors. Conclusions/Significance: These studies demonstrate generalizability of radioactive OI technique. It provides a new molecular imaging strategy and will likely have significant impact on both small animal and clinical imaging.