Abstract：Objective: To investigate the dose of first-pass perfusion and the best delayed scanning time. Thereby, the purpose is to get a better cardiac perfusion MRI images and the best delay-enhanced images. Method: Five experimental pigs with myocardial infarction underwent two MR myocardial first-pass perfusion imaging, the contrast agent dose were 0.05mmol/kg and 0.1mmol/kg respectively. Ten experimental pigs with myocardial infarction underwent delayed enhanced MR imaging at 5min, 10min, 30min, 40min time point. The results were analyzed statistically. Result: There was statistical difference(P<0.05) between the two groups(0.05mmol/kg and 0.1mmol/kg) in detection of the myocardial perfusion decrease or defect on the first-pass MR perfusion imaging. The data of the delayed enhancement MR imaging in different scanning time showed. ①The signal values were statistically significant between 10 minutes and 5 minutes, 40 minutes and 30 minutes; ②The signal values of myocardial infarction showed rise in the stage of 5～10 minutes; and the signal values were relatively stable in the 10～30 minutes; During the stage of 30～40 minutes, the signal value of myocardial infarction showed a clear downward trend compared with the previous time. Conclusion: The perfusion imaging quality of the dose of the 0.1mmol/kg group is better than the 0.05mmol/kg group. It can detect more myocardial perfusion defects. Delayed time between 10～30min is the best scanning time to the delayed enhancement MR imaging. These are helpful in the assessment of myocardial viability using MR first-pass myocardial perfusion imaging and delayed enhancement MR imaging.
2010, Vol. 21 
