Thin-slice Free-breathing Pseudo-golden-angle Radial Stack-of-stars with Gating and Tracking T₁-weighted Acquisition: An Efficient Gadoxetic Acid-enhanced Hepatobiliary-phase Imaging Alternative for Patients with Unstable Breath Holding

Purpose: To compare four free-breathing scan techniques for gadoxetic acid-enhanced hepatobiliary phase imaging with conventional breath-hold scans.

Materials and methods: Gadoxetic acid-enhanced hepatobiliary phase imaging with six image acquisition sets performed in 50 patients. Image acquisition sets included fat-suppressed 3D T₁-weighted turbo field echo with free-breathing pseudo-golden-angle radial stack-of-stars (FBRS) acquisition, FBRS with track (FBRS_T), FBRS with gate and track (FBRS_G&T), thin-slice FBRS with gate and track (thin-slice FBRS_G&T), free-breathing Cartesian acquisition (Cartesian_FB), and breath-hold Cartesian acquisition (Cartesian_BH). Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and image quality compared to the six-image acquisition sets.

Results: Signal-to-noise ratio and CNR were significantly higher in FBRS, FBRS_T, FBRS_G&T, and thin-slice FBRS_G&T than in Cartesian_FB and Cartesian_BH (P < 0.001). Based on sharpness, motion artifacts, visibility of intrahepatic vessels, and overall image quality, thin-slice FBRS_G&T had the highest image quality followed by Cartesian_BH and FBRS_G&T (P < 0.001). Severe motion artifacts were observed in 25 patients in Cartesian_FB and three patients in Cartesian_BH, whereas image quality remained above the acceptable range in FBRS_G&T, FBRS_T, FBRS, and thin-slice FBRS_G&T in all cases.

Conclusion: Thin-slice FBRS_G&T demonstrated excellent image quality compared with conventional Cartesian_BH in gadoxetic acid-enhanced hepatobiliary phase imaging. It can be apply to supplemental sequences of patients with unstable breath holding.