Assessment of fast dynamic imaging and the use of Gd-EOB-DTPA for MR-guided liver interventions.

PURPOSE

1. To analyze and compare fast dynamic imaging sequences to biopsy suspect liver lesions. 2) To evaluate the additional use of hepatocyte-specific contrast agent compared to the nonenhanced fast dynamic scans and diagnostic liver imaging.

MATERIALS AND METHODS

Image acquisition was performed using a 1T open-configured scanner suitable for interventional purposes. Transversal postcontrast T1-weighted (T1w) fat-saturated 3D high-resolution examination (THRIVE) images were acquired >20 minutes postintravenous application of gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA). A single slice, crossing the level of the lesion, was acquired using intermediate-weighted steady-state free-precession (bTFE), T1w-gradient echo and spin echo (T1FFE/TSE), T2w-spin echo (sshTSE) sequences. T1w imaging was acquired prior and after contrast media application. Diagnostic and fast dynamic images were compared based on a 10-point rating scale. In addition, the liver-to-lesion-contrast ratio was measured.

RESULTS

A total of 39 malignant lesions with a mean diameter of 13 mm (5-30 mm) in 39 patients were included. Concerning a test of noninferiority, there was no significant difference between rating score values of fast dynamic imaging employing contrast-enhanced T1FFE-sequences compared to diagnostic THRIVE (P = 0.001). Calculated liver-to-lesion contrast also showed no difference for either imaging sequence (P = 1.0). All other sequences tested showed significant inferiority (P ≤ 0.001).

CONCLUSION

T1w Gd-EOB-DTPA contrast-enhanced fast dynamic GRE imaging significantly improves the contrast behavior of malignant liver lesions comparable to diagnostic imaging and is best suited for liver intervention, especially at 1T open magnetic resonance imaging.