New magnet to sharpen imaging capabilities at Vanderbilt

The Vanderbilt University Institute of Imaging Science has received a $3.45 million federal stimulus grant to purchase one of the world’s strongest magnetic resonance imaging (MRI) scanners.

The 15 Tesla scanner will be used in studies of genetically engineered mice and other small animal models to further understanding of cancer, diabetes and brain disorders in humans.

One Tesla is roughly 20,000 times the strength of the magnetic field of the earth. Because the 15 Tesla scanner is so mighty, it can generate exquisitely detailed images of the brain and other body structures, and measure minute levels of key compounds, including cancer “biomarkers.”

Since these imaging methods are non-invasive, they can be conducted repeatedly in living animals.

For these reasons, “magnetic resonance imaging and spectroscopy have become very powerful tools for studying … animal models of disease and effects of genetic manipulations,” said institute director John Gore, professor of biomedical engineering.

The one-year stimulus grant to purchase the scanner was awarded through the National Center for Research Resources, part of the National Institutes of Health (NIH).

It is the sixth largest grant awarded to Vanderbilt University by the NIH under the American Recovery and Reinvestment Act. To date, the NIH has provided nearly $90 million to support 186 different stimulus grants led by 165 Vanderbilt scientists.

The new Varian scanner is smaller than scanners used in human studies, and will be installed in renovated space in Medical Center North, Gore said.

Here are some of the ways the instrument will be used:

Eduard Chekmenev, Ph.D., who came to Vanderbilt last year from the California Institute of Technology, and Kevin Waddell, Ph.D., are developing a way to “hyperpolarize” carbon-13, a stable isotope of carbon, so that it can be used as a novel imaging biomarker for cancer. One day it could help doctors monitor the response of tumors to drug treatment.

The scanner also will be used to study the effects of specific genetic modifications and novel drugs on brain structure and function, including the development of the important signaling systems involving the neurotransmitters serotonin and dopamine. Such studies could lead to new, more effective treatments for disorders as wide-ranging as depression and Parkinson’s disease.

Metabolic disorders
The scanner will enable researchers to study leptin and melanocortin receptor signaling in the mouse brain. These compounds are involved in feeding behavior and the regulation of body weight. The research has implications for better understanding the development of obesity and diabetes, and could lead to better ways to treat and prevent these all-too-common human conditions.

Imaging science
Other researchers will investigate and develop new imaging methods such as diffusion tensor imaging, a non-invasive technique for studying the “white matter,” bundles of long fibers (axons) that transmit signals between different parts of the brain.

The stimulus grant is the latest in a series of investments by the National Center for Research Resources. Since 2004, the center has provided nearly $14 million in equipment and infrastructure grants to the Institute of Imaging Science, Gore said.

The institute’s $20 million building at the corner of Medical Center Drive and 21st Avenue South, dedicated in 2006, includes four floors of research, office and classroom space, four powerful magnets for conducting studies in animals, and a 7 Tesla scanner for use in humans.

“We probably have the single largest, most comprehensive center in the country,” said Gore, who was recruited from Yale University in 2002 to establish the institute. “Size isn’t everything, but there are not many areas in which we’re not considered to be major players.”