Is liver lesion characterisation by simplified IVIM DWI also feasible at 3.0 T?

To evaluate simplified intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) for liver lesion characterisation at 3.0 T and to compare it with 1.5 T.

3.0-T DWI data from a respiratory-gated MRI sequence with b = 0, 50, 250, and 800 s/mm² were analysed in 116 lesions (78 patients) and 27 healthy livers. Apparent diffusion coefficient ADC = ADC(0,800) and IVIM-based parameters D₁' = ADC(50,800), D₂' = ADC(250,800), f₁' = f(0,50,800), f₂' = f(0,250,800), D*' = D*(0,50,250,800), ADC_low = ADC(0,50), and ADC_diff = ADC_low-D₂' were calculated voxel-wise and analysed on per-patient basis. Results were compared with those of 173 lesions (110 patients) and 40 healthy livers at 1.5 T.

Focal nodular hyperplasias were best discriminated from all other lesions by f₁' and haemangiomas by D₁' with an area under the curve (AUC) of 0.993 and 1.000, respectively. For discrimination between malignant and benign lesions, ADC was best suited (AUC of 0.968). The combination of D₁' and f₁' correctly identified more lesions as malignant or benign than the ADC (99.1% vs 88.8%). Discriminatory power for differentiating malignant from benign lesions tended to be higher at 3.0 T than at 1.5 T.

Simplified IVIM is suitable for lesion characterisation at 3.0 T with a trend of superior diagnostic accuracy for discriminating malignant from benign lesions compared with 1.5 T.

• Simplified IVIM is also suitable for liver lesion characterisation at 3.0 T. • Excellent accuracy was reached for discriminating malignant from benign lesions. • The acquisition of only three b-values (0, 50, 800 s/mm ² ) is required.