Enhancing liver diffusion-weighted imaging quality with correlation-weighted averaging: notable benefits in the left hepatic lobe.

PURPOSE: To evaluate the feasibility of correlation-weighted averaging factor (CWAF) in liver diffusion-weighted imaging (DWI).

MATERIALS AND

METHODS

This prospective study included 103 participants who underwent liver MRI. DWI were reconstructed using both original data (DWIOriginal) and CWAF-corrected data (DWICWAF). Two radiologists independently assessed high-b DWI images for overall image quality, image noise, hepatic edge sharpness, and lesion conspicuity in the right and left lobes using five-point scales. Signal intensity ratio (SIR) and apparent diffusion coefficient (ADC) values were measured in four hepatic segments and in liver lesions, with lesion measurements analyzed separately for each lobe. These parameters were compared between the two image sets.

RESULTS

The scores for overall image quality (P < 0.001), image noise (P < 0.001), and hepatic edge sharpness in the right lobe (P = 0.001) were higher in DWIOriginal compared with DWICWAF. In contrast, hepatic edge sharpness (P < 0.001) and lesion conspicuity (P < 0.001) in the left lobe were superior in DWICWAF. Liver and lesion SIRs were higher in DWICWAF across all segments than in DWIOriginal (P < 0.007). Liver ADC values were lower in DWICWAF than in DWIOriginal in all segments (P < 0.001). Lesion ADC values were also lower in DWICWAF than in DWIOriginal in the right lobe (P < 0.001) but were not different in the left lobe (P = 0.48).

CONCLUSION

CWAF improved hepatic edge sharpness and lesion conspicuity in the left lobe, although overall image quality was slightly reduced. ADC values were generally lower in DWICWAF than in DWIOriginal.