Authors' Affiliations: 1Department of Biomedical Engineering, 2The Vanderbilt University Institute of Imaging Science (VUIIS), 3Department of Radiology and Radiological Sciences, 4Program in Chemical and Physical Biology, 5Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, Tennessee; and 6OSI Pharmaceuticals, In Vivo Pharmacology, Boulder, Colorado (At 2011-05-15)