Arterial visualization by contrast-enhanced moving-table MR angiography: Crossover comparison of 0.1 and 0.2 mmol/kg doses of meglumine gadopentetate in normal volunteers

Purpose: To determine the appropriate dose of contrast medium for moving-table MR angiography (MT-MRA) from the abdominal aorta to the ankle by comparing visualization with different doses of meglumine gadopentetate (Gd-DTPA) administered in crossover fashion to normal volunteers. Materials and Methods: Twelve healthy adults underwent imaging after crossover administration of 0.1 and 0.2 mmol/kg of Gd-DTPA in random order. Continuous MT-MRA was performed with a fast 3D spoiled gradient echo sequence without parallel imaging technique. Visualization was evaluated in a total of 252 arteries by three blinded readers who independently rated arterial visualization using a 5-grade scale. Signal Intensity was determined and the blood concentration of Gd-DTPA was estimated. Results: Arterial visualization in the lower leg region was significantly better with a dose of 0.2 mmol/kg than with 0.1 mmol/kg (P < 0.001). For all regions assessed the estimated blood Gd-DTPA level was significantly higher with 0.2 mmol/kg than with 0.1 mmol/kg (abdominal aorta, P = 0.030; superficial femoral artery, P < 0.001; posterior tibial artery, P = 0.039). The vascular signal enhancement ratio and artery-to-muscle signal ratio were significantly higher in the upper leg and lower leg regions at 0.2 mmol/kg. Conclusion: With continuous MT-MRA imaging from the abdomen to the ankle in normal volunteers, better arterial visualization and superior contrast were achieved with 0.2 mmol/kg of Gd-DTPA.