NA-23 MAGNETIC-RESONANCE-IMAGING - DISTRIBUTION OF BRINE IN MUSCLE

Magnetic resonance imaging (MRI) has been used to characterize tissues in morphological studies. Here, Na-23 NMR imaging was used to study t he distribution in muscle of brine (5 M NaCl), injected before onset o f rigor mortis. First, the distribution of brine was monitored in exci sed muscle from rabbits for 6 hr following arterial brine injection. I mmediately after injection, distribution was clearly heterogeneous. Af ter 6 hr, a steady state was achieved but the observed brine distribut ion was not fully homogeneous. Second, the same was done for ham proce ssed in various ways (tumbling, cooking). Tumbling increased the homog eneity of distribution in our experimental conditions but only cooking afforded full homogenization of brine in ham. Concentrations of NMR-v isible sodium in the muscles were appreciably lower than the expected values calculated from the volume of injected brine. The invisible sod ium presumably has T-2 values which are too short compared with the ec ho time in our conventional spectrometer.