EFFECT OF PERIPHERAL-NERVE INJURY ON NUCLEAR-MAGNETIC-RESONANCE RELAXATION-TIMES OF RAT SKELETAL-MUSCLE

RATIONALE AND OBJECTIVES. The authors evaluate the changes in magnetic resonance (MR) relaxation times of rat skeletal muscles in vivo after nerve injury and during neural recovery, and determine the major dete rminants of relaxation times, MATERIALS, Magnetic resonance relaxation times, blood volume, and water and fat content were examined after ne rve injury and during recovery with time course, RESULTS. Nerve injury led to longer T2 values compared with controls, but there were no sig nificant changes in T1 values. After the initial prolongation of T2 af ter nerve injury, no changes were observed, Neural recovery resulted i n a return of T2 values to normal, The time course of changes in blood volume was similar to that of changes in T2, and T2 values were corre lated strongly with 19-fluorine-MR spectroscopy estimates of blood vol ume (r2=0.94), CONCLUSIONS, T2 values may be useful to monitor recover y after nerve injury and may be related to the blood volume in skeleta l muscle.