Evaluation of tissue perfusion in a rat model of hind-limb muscle ischemia using dynamic contrast-enhanced magnetic resonance imaging

Purpose To evaluate the feasibility of using dynamic contrast‐enhanced magnetic resonance imaging (MRI) for assessment of muscle perfusion in a rat model of hind‐limb ischemia. Materials and Methods The acute alteration and chronic recovery in muscle perfusion and perfusion reserve after femoral artery ligation were quantified using the maximum Gd‐DTPA uptake rate obtained by a T1‐weighted gradient‐recalled echo sequence. Radionuclide‐labeled microsphere blood flow measurements were performed for comparison with the MR perfusion measurement on a separate set of animals. Results After femoral artery ligation, a significant reduction in resting muscle perfusion was only observed at 1 hour post‐ligation during the 28‐day follow‐up period. Muscle perfusion reserve was severely diminished following the ligation. Despite significant recovery over time, perfusion reserve to the ligated limb reached only 63% of the perfusion capacity in the unaffected limb by 42 days post ligation. A strong correlation (r = 0.86) between MR perfusion and microsphere blood flow measurements was observed for evaluation of relative changes in muscle perfusion. Conclusion Dynamic contrast‐enhanced MRI with Gd‐DTPA is useful to assess time‐dependent changes in muscle perfusion and perfusion reserve in this hind‐limb ischemia model. J. Magn. Reson. Imaging 2002;16:277–283. © 2002 Wiley‐Liss, Inc.