Dose‐dependence of transient respiratory motion artifacts on gadoxetic acid‐enhanced arterial phase MR images

Purpose To compare the occurrence of transient respiratory motion (TM) artifacts between 0.05 mmol/kg and 0.025 mmol/kg gadoxetic‐acid on arterial phase MRI intra‐individually for evaluating dose‐dependence of gadoxetic acid. Materials and Methods This retrospective study involved 91 patients who underwent dynamic MRI at 1.5T at different times, one time with 0.05 mmol/kg and the other 0.025 mmol/kg gadoxetic‐acid. Examinations with 0.05 mmol/kg totaled 91 scans, and examinations with 0.025 mmol/kg totaled 375 scans (due to multiple exams for several patients). The scan with 0.025 mmol/kg closest in time to the 0.05 mmol/kg scan was selected to minimize temporal effects. Two radiologists graded TM artifacts in the arterial phase images using a four‐point scale: no, mild, moderate, and severe artifacts. Results were compared between the two protocols (0.05 mmol/kg versus all 0.025 mmol/kg and 0.05 mmol/kg versus selected 0.025 mmol/kg), and the odds ratio for moderate‐to‐severe artifacts was calculated. Results Significantly more TM artifacts were observed in the double dose (16/91 [17%]) scans compared with either all (17/375 [4%]; P  < 0.01) or selected (3/91 [3%]; P  = 0.01) standard dose scans. The odds ratio of the moderate‐to‐severe artifacts with the higher dose was 4.99–5.33. Conclusion There appears to be dose‐dependence of gadoxetic‐acid and the occurrence of TM artifacts. Level of Evidence: 3 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;47:433–438.