Small laboratory animal models such as mice, rats and hamsters are widely used throughout the biomedical research community at Washington University in St. Louis and other scientific institutions. With the recent revolution in molecular biology, transgenic laboratory animal models - in particular mice - have become an indispensable part of the biomedical research armamentarium. The identification and development of methods for analyzing and evaluating the characteristics of interest within animal models remains a significant challenge. This is especially true for longitudinal studies, in which members of a sample population are followed over an extended period. Clearly, invasive and/or destructive procedures - especially those that require sacrifice of the subject - are incompatible with such studies. Under these circumstances, nondestructive imaging procedures, such as those offered by magnetic resonance imaging (MRI), are especially valuable. This application from the Washington University Biomedical Magnetic Resonance Laboratory, home to the Washington University Small-Animal Imaging Resource, requests funds to purchase a state-of-the-art 11.74 tesla (500 MHz) MRI console from Varian NMR Systems, Palo Alto, CA. The 11.74 tesla small-animal MRI scanner in question was purchased with a 2002 NIH High-End Instrumentation award and is one of a handful of ultra high field scanners world-wide. It is heavily used in a variety of cross-disciplinary research studies, ranging from evaluation of cell culture systems to rodents, for which high signal-to-noise and contrast- to-noise ratios are critical. The requested console is Varian's new generation DirectDrive"""""""" instrument model, which replaces its long running INOVA"""""""" line. The current Varian INOVA console is outdated and unable to adequately support researchers who often push the limits of modern MRI science. Varian's DirectDrive console architecture represents a major leap in MR engineering technology, integration, and instrument performance. Importantly, the DirectDrive system supports parallel imaging in a cost effective manner. The console configuration requested includes four transmitter/receiver channels to enable parallel imaging via phased array coils. It also provides markedly superior in phase stability and event timing accuracy for fcMRI, qBOLD, and other demanding studies and can significantly reduce imaging artifacts through increased dynamic range and by eliminating quadrature imbalance.
Small-animal models of disease, pathology, and injury represent an important biomedical research tool. Magnetic resonance imaging provides a noninvasive and nondestructive means to translate preclinical findings from small-animal models to the clinic, directly impacting health care. This program requests funds to upgrade an ultra high magnetic field small-animal MRI scanner to enhance it capabilities, thereby supporting health care researchers.
| Spees, William M; Buhl, Niels; Sun, Peng et al. (2011) Quantification and compensation of eddy-current-induced magnetic-field gradients. J Magn Reson 212:116-23 |
