Feasibility of Half-Dose Gadoxetic Acid-Enhanced Liver MRI at 5.0 T: A Prospective Intrapatient Comparison with Full-Dose 3.0 T

RATIONALE AND OBJECTIVES: This study aims to determine if half-dose gadoxetic acid-enhanced liver magnetic resonance imaging (MRI) at 5.0 T is feasible by comparing with full-dose MRI at 3.0 T. MATERIALS AND METHODS: 19 patients with liver disease underwent both full-dose (0.025 mmol/kg) gadoxetic acid-enhanced 3.0-T MRI and half-dose (0.0125 mmol/kg) 5.0-T MRI. Quantitative image quality was assessed by measuring the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and contrast enhancement index (CEI) in liver and hepatic lesions. Qualitative image quality and respiratory motion artifacts were evaluated. Statistical comparisons were performed using paired t-tests or the Wilcoxon signed-rank test. RESULTS: Half dose 5.0-T MRI yielded significantly higher SNRs in liver and hepatic lesions compared to full-dose 3.0-T MRI (all P < 0.001). The 15-minute hepatobiliary phase (HBP) at 5.0 T achieved image quality comparable to 20-minute HBP at 3.0 T. Specifically, at the 15-minute HBP, the 5.0-T protocol demonstrated significantly higher liver SNR (77.24 ± 12.08 vs. 51.84 ± 8.18 at 20 min for 3.0 T; P < 0.001) and liver-to-lesion CNR (38.93 ± 15.56 vs. 25.37 ± 9.43; P < 0.01). Additionally, respiratory motion artifacts in the early arterial phase were significantly reduced at 5.0 T (1.12 ± 0.33 vs. 1.62 ± 0.86; P < 0.05). CONCLUSION: Liver 5.0-T MRI with a half-dose of gadoxetic acid maintains diagnostic image quality while enabling a 25% reduction in HBP acquisition time and mitigating motion artifacts. This technique represents a viable strategy to improve scanning efficiency and patient safety in gadoxetic acid-enhanced liver imaging.