Many standard MRIs are 1.5 Tesla and high-end clinical units are 3 Tesla, a measure of the density and intensity of a magnetic field. MCGs small animal MRI is 7 Tesla, not the strongest magnet available for research but one that enables good quality images of small organs which are comparable to those obtained by clinical machines. Its pretty close to clinical grade, says Dr. Yanasak. But since you are scanning something smaller you need a larger field of strength to get the animal images to look like a human image, he says. The smallest heart theyve imaged, for example, is that of a 3-gram mice (thats a .105-ounce mouse). It is better resolution in the sense that you have to have better resolution to see a brain this big, Dr. Yanasak says, holding his fingers very close together.
The textbook answer for why scientists need high-tech imaging studies" They are noninvasive, says Dr. Hu, which obviously makes them excellent clinical tools as well. If you have an animal disease model, for pretty much any noninvasive technique, the advantage is it reduces animal use tremendously, he says.
Like physicians do with patients, basic scientists now use technology to help monitor disease progression over time and even to see if treatments work. In his own work, for example, Dr. Hu watches development of heart failure by monitoring changes in calcium dynamic and heart structure.
Newer technology, on loan to the facility from Xenogen Corp, part of Caliber Life Sciences Corp., has enabled the lab to throw genetic expression into the mix. The optical scanning system uses luciferase, the same enzyme fireflies use to glow, to identify gene expression.
"If you combine (luciferase) with certain genes and the genes are expressed, they
|Contact: Toni Baker|
Medical College of Georgia