Figure 2b. Coronal three-dimensional time-resolved MR angiograms (4.0/1.65 with 25° flip angle) of the renal arteries in anteroposterior maximum intensity projection images. Differences in SNR were not significant between the two dose groups. (a) First image obtained after power injection of gadopentetate dimeglumine 0.1 mmol/kg followed with saline reveals hemodynamically nonsignificant stenosis of the left renal artery (right arrow) that was detected and graded correctly by all four observers. The hemodynamically significant stenosis of the right renal artery (left arrow) was detected and graded correctly by all four observers. (b) First image obtained after power injection of gadopentetate dimeglumine 0.2 mmol/kg followed with saline. No stenosis was detected.