Relationship between transient severe motion of the liver in gadoxetic acid or iodinated contrast agent-enhanced imaging and arterial oxygen saturation and heart rate changes

Purpose: To clarify the relationship between transient sever motion artifact in arterial phase (TSMA) and changes in peripheral capillary oxygen saturation (SpO(2)) and heart rate (HR) after contrast media administration during MRI or CT of the liver. Methods: 87 patients undergoing 61 MRI examination with gadoxetic acid or 26 CT examination with iodinated contrast were included. Dynamic contrast-enhanced imaging (DCEI) was obtained at four vascular phase acquisitions. Reviewers extracted the segmental data of SpO(2) and HR in each phase from consecutive data in DCE-CT or DCE-MRI. In addition, reviewers scored for respiratory motion in each phase using 5-point scale. Patients with an arterial score of 4-5, and other phase scores of 1-2 were considered to be exhibiting TSMA. Results: In gadoxetic acid, mean SpO(2) of arterial phase was significantly lower than three other phases (P = 0.045 to P < 0.001). However, the decrease in SpO(2) in arterial phase compared with other phases was < 1%. Mean HR in gadoxetic acid or iodinated contrast agent was highest in the portal-phase. The incidence of TSM was 0% in patients with iodinated contrast agent and was 8.2% (5/61 patients; TSM group) in patients with gadoxetic acid, respectively. In addition, there was no significant difference in mean SpO(2) of arterial phase between the TSM group (97.5% +/- 1.08%) and non-TSM group (96.4% +/- 1.85%) (P = 0.219). Conclusion: The slight decrease in SpO(2) in arterial phase is not associated with TSMA.