Ultra low-field Gd-DTPA-enhanced MR imaging

Phantoms with MR properties closely mimicking those of tissue were developed by using an argarose matrix mixed with varying concentrations of Gd-DTPA (0.5 M to 0.0000004 M). Phantoms were scanned by using various pulse sequences, including three-dimensional acquisition. Patient examinations included a standard dosage bolus of contrast material, intravenous drip of contrast material, and bolus with intravenous drip infusion. A readily identifiable signal intensity of Gd-DTPA was achievable at 0.064 T under both laboratory and clinical conditions. This paper reports that improvement in signal intensity might be achieved by the combination of bolus and drip infusion of Gd-DTPA with three- dimensional acquisition (TR/TE = 65/24 [repetition time/echo time, msec]; FA = 90)