Jack Thomas Skinner1,2, Mark D. Does1,2
1Institute of Imaging Science, Vanderbilt University, Nashville, TN, USA; 2Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
MRI provides an excellent way of visualizing muscle inflammation; however, there are few techniques that serve to quantitatively assess edematous muscle. To investigate changes in relaxation times with injury, a graded edema model in rats was produced by subcutaneous injections of a l-carrageenan solution at varied concentrations. Saturation recovery prepared multiple spin-echo (SR-ME) measurements at 9.4T revealed both multiexponential T1 and T2 in edematous muscle. A decrease in injection concentration resulted in a decrease in the volume fraction of the long-lived component and a decrease in T1. These results indicate that relaxation times can be markers of muscle injury severity.