Image Quality and Focal Lesion Detectability Analysis of Multiband Variable-Rate Selective Excitation Diffusion-Weighted Imaging of the Liver Using 3.0-T MRI

Abstract

Purpose: Acquisition time reduction in diffusion-weighted imaging (DWI) can be achieved by the combining multiband and variable-rate selective excitation (MB-VERSE). This study attempted to evaluate and compare the image quality (IQ) and focal lesion detectability of the respiratory-triggered MB-VERSE DWI with conventional DWI for liver magnetic resonance imaging. Materials and Methods: The acquisition time, IQ, and focal lesion detectability of MB- VERSE DWI and conventional DWI were compared in 144 patients. Qualitative (overall IQ, IQ at the liver dome, sharpness of the liver margin, and degree of artifacts) and quantitative (signal-to-noise ratio [SNR], contrast-to-noise ratio [CNR], and apparent diffusion coefficient) IQ parameters were compared with the Wilcoxon signed-rank test. The diagnostic accuracy for focal lesion detectability was estimated with the mean figure of merit (FOM) from the area under the jackknife alternative free-response receiver operating characteristic curve. Results: The MB-VERSE DWI exhibited significantly shorter scan time (153.1 +/- 34.5 s vs. 225.1 +/- 33.0 s, p < 0.001), poorer qualitative IQ (3.4 vs. 3.9, p < 0.001), lower SNR (34.4 vs. 50.0, p < 0.001), but comparable CNR (57.5 +/- 49.0 vs. 78.9 +/- 75.6, p = 0.070) compared to those of the conventional DWI. The MB-VERSE DWI exhibited similar per-lesion sensitivities (85.1%-88.1% vs. 88.1%-92.5%) and specificities (99.7%-99.8% vs. 99.5%-99.8%) of focal lesion detectability (p > 0.050) and similar diagnostic accuracy (FOM, 0.958 vs. 0.957, p = 0.583) compared to those of the conventional DWI. Conclusion: MB-VERSE DWI exhibited a significantly shorter acquisition time than conventional DWI, with compromised overall IQ and lower SNR but preserved CNR and focal liver lesion detectability. MB-VERSE DWI may be a useful alternative for patients requiring a short acquisition time.