January 27, 2006

Imaging capabilities rising with technology

Featured Image

Blood vessels nourishing a breast tumor are represented by red voxels (three-dimensional data points) in a dynamic contrast-enhanced MRI. The hope is that this kind of analysis will enable doctors to determine, early on, whether the tumor is responding to therapy.
Image courtesy of Tom Yankeelov, Ph.D.

Imaging capabilities rising with technology

Researchers at Vanderbilt University Medical Center are using imaging technologies to monitor drug therapy in cancer patients, improve the treatment of addiction, and advance understanding of inflammation.

“The new technologies build on advances in other fields such as molecular biology and proteomics, and have enormous potential to improve clinical care and to make important contributions to medical research,” said John C. Gore, Ph.D., director of the Vanderbilt University Institute of Imaging Science.

The multidisciplinary institute, founded in 2002, provides Vanderbilt researchers with state-of-the-art research imaging of animals and human subjects across a broad range of modalities, from computerized tomography (CT) and positron emission tomography (PET) to ultrasound and optical imaging.

In the fall of 2006, the institute will move into a new 42,000-square-foot building at the corner of Garland Avenue and 21st Avenue South.

Along with chemistry labs dedicated to the development of new probes for molecular imaging and computing labs for advanced image analysis, the building will house a 7 Tesla human scanner for magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS).

One Tesla is roughly 20,000 times the strength of the magnetic field of the earth.

The 7 Tesla magnet, one of fewer than 10 such systems in the world, will enable researchers to generate images down to the molecular level.

Already Vanderbilt scientists are studying a host of new imaging technologies and applications.

Dynamic contrast-enhanced MRI is being tested in women with breast cancer to see whether their tumors are responding to chemotherapy. If successful, the technique could avoid the need for repeat biopsies, said Tom Yankeelov, Ph.D., assistant professor of Radiology and Radiological Sciences who directs the institute's cancer imaging program.

“That is why imaging is so powerful,” Yankeelov said. “You can get a more complete description of the tumor status, and you can do it non-invasively.”

Ronald L. Cowan, M.D., Ph.D., assistant professor of Psychiatry and Radiology, is using functional MRI to study how brain activation changes over time in response to amphetamine, a powerful stimulant.

“We're hoping to find a part of the brain early on that gets activated before the experience of euphoria,” Cowan said.

“That might give us a target for therapy, or at least for further study.”

Using luciferase, the same enzyme that produces the firefly's glow, Timothy S. Blackwell, M.D., associate professor of Medicine, is studying gene expression in a mouse model of lung inflammation and injury.

Bioluminescence imaging “is helping us to define the balance of factors that cause either lung injury or effective host defense against infection,” he said. “Ultimately we might be able to come up with ways to prevent injury and still maintain adequate defenses.”

These advances, and more, will be featured in the next issue of the medical center's research magazine, Lens, to be published in early February.

To obtain a copy of Lens, e-mail the editor, Bill Snyder, at William.snyder@vanderbilt.edu or call 322-4747.