DETECTION OF LIVER FIBROSIS WITH MAGNETIC CROSS-RELAXATION

The utility of MRI using magnetization transfer (MT) enhanced pulse se quences to diagnose hepatic cirrhosis in a rat model was investigated. Hepatic T-1, was measured with and without MT off-resonance RF pulses in 17 treated and six control rats. The livers were evaluated histolo gically, and the hydroxyproline content quantitatively measured. We di d not find a statistically significant linear correlation between the MR relaxation times and the degree of tissue injury. However, the MR m easurements performed with MT were superior to those without different iating the treated and control groups. Specifically the T-1 times were 695 +/- 76 ms for the treated group, versus 748 +/- 61 ms in the cont rols; P = 0.095. The T-1sat times were also lower in the treated group , with statistical significance: 367 +/- 51 ms versus 421 +/- 38 ms, P = 0.016. Finally, the change in the relaxation rates (the inverse of the relaxation times) with and without saturation were 1.31 +/- 0.22 s (-1) (treated group) versus 1.05 +/- 0.12 s(-1) (controls), which diff ered significantly, P = 0.001.