Don Rauf

CONTEXT: While prostate-specific antigen testing and biopsy are the most conclusive ways for detecting prostate cancer, no clear-cut imaging technique exists for initial diagnosis and staging.

FDG-PET imaging has become an accepted, reimburseable approach for diagnosing Alzheimer's and other neurodegenerative diseases.

The emerging therapy of islet transplantation has shown great promise for diabetes patients.

CONTEXT: Combining proton MR spectroscopic imaging, sodium MR, and PET/CT imaging may be an effective multimodality approach for detecting early response to chemotherapy in breast cancer patients, according to Dr. Michael Jacobs, a radiologist at Johns Hopkins School of Medicine.

CONTEXT: Intra-arterial therapy with beta-irradiating yttrium (90Y) microspheres (Therasphere) has demonstrated significant therapeutic benefit in patients with hepatocellular carcinoma.

CONTEXT: Dr. Dushyant Sahani, director of CT at Massachusetts General Hospital in Boston, evaluated the effects of the anti-angiogenic drug bevacizumab (Avastin, Genentech) on patients with advanced hepatocellular carcinoma (HCC). Perfusion CT was used compare changes in tumor perfusion with tumor size and biomarkers such as alpha-fetoprotein (AFP) and circulating endothelial cells (CEC).

CONTEXT: Neuroradiology fellow Dr. Roula Hourani at Johns Hopkins University researched the ability of proton MR spectroscopy (MRS) to differentiate between benign brain neoplasia and tumors in children. Potentially, such a non-invasive diagnostic approach would most benefit children with non-neoplastic lesions and less accessible tumors that could be treated by radio- or chemotherapy.

CONTEXT: Contrast-enhanced ultrasound (CEU) using targeted microbubble agents has already been proved effective for imaging angiogenesis in tumors and the vasculature. Building on this technique, researchers in the cardiovascular division of the University of Virginia in Charlottesville have demonstrated that microbubbles targeted to endothelial integrins can provide early CEU evaluation of ischemia and response to proangiogenic growth factor therapies-before recovery of tissue perfusion.

Discoveries relating to the imaging of hypoxia, angiogenesis, and ligand receptors demonstrate the scientific prowess of the In vivo Cellular Molecular Imaging Center at Johns Hopkins University and justify its reputation as one of the top molecular imaging laboratories in the world.

CONTEXT: Dr. Markus Schwaiger and colleagues at the Technical University of Munich, Germany, have demonstrated that successful transfer of the vascular endothelial growth factor (VEGF) gene results in an increase of tissue perfusion without impairing cardiac contractile function or morphology.

When Dr. Ralph Weissleder founded the Center for Molecular Imaging Research at Massachusetts General Hospital in 1994, he had a staff of only two people conducting research in a 200-square-foot space. Flash forward just over a decade, and the CMIR has expanded to one of the largest divisions of the hospital's vast department of radiology. The CMIR fills more than 12,000 square feet with a staff of 80 scientists and 40 postdoctoral fellows. Weissleder and colleagues have made discoveries responsible for defining the cardinal principles of molecular imaging and their revolutionary implications for radiologic practice.

Despite political pressure favoring tighter drug regulations, the FDA has prepared a plan that may hasten the testing and approval of investigational molecular imaging agents.

Dr. Zahi Fayad and Dr. Juan C. Frias at Mount Sinai School of Medicine in New York City and Dr. Edward Fisher at New York University School of Medicine have developed a high-density lipoprotein (HDL)-like nanoparticle for imaging atherosclerotic plaques in vivo. The researchers removed lipids from normal human HDL cholesterol. Apolipoproteins were extracted and reconstituted with the phospholipid-based contrast agent gadolinium-DTPA-DMPE and NBD-DPPE, a fluorescent phospholipid with a green emission. The Gd-DTPA-DMPE becomes incorporated in the reconstituted particle. (An approximately 9-nm diameter contains 15 to 20 molecules of Gd-DTPA-DMPE.)

Stroke patients given a thrombolytic agent along with continuous ultrasound monitoring fared better than patients who received thrombolysis alone. Accelerating the dissolution of emboli could potentially increase the duration of the critical three-hour window in which lysis must be performed, according to a study in The New England Journal of Medicine.

As more women in the U.S. turn to mammography to detect breast cancer, the availability of mammographers and technologists certified for breast imaging is decreasing, according to a survey published in the May issue of Radiology.