Enhanced diagnostic performance of WE-SHARP-DWI compared with SPAIR-DWI for focal liver lesion evaluation at 3T

This study aimed to compare the diagnostic performance of 2 fat suppression techniques in diffusion-weighted imaging (DWI) for detecting and assessing focal liver lesions (FLLs): water excitation spectral heterogeneity adaptive radiofrequency pulses (WE-SHARP) and conventional spectral adiabatic inversion recovery (SPAIR).

This prospective study enrolled eligible participants between October 2023 and August 2024. Various DWI techniques at 3T, SPAIR-DWI, WE-SHARP-DWI, and WE-SHARP-DWI with correction algorithms (WE-SHARP-DWI*), acquired at b values of 50, 400, 800, and 1200 s/mm², were used to evaluate FLLs. Two radiologists independently assessed several subjective image quality parameters: liver edge sharpness, vessel delineation, lesion conspicuity, fat suppression effectiveness, artifacts, and overall image quality. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and apparent diffusion coefficient (ADC) values were also measured. The diagnostic performance of all 3 sequences was evaluated using receiver operating characteristic (ROC) curve analysis.

The study included 158 patients (67 with malignant and 91 with benign lesions) and 25 volunteers. Compared with SPAIR-DWI, the subjective image quality parameters were superior for both WE-SHARP sequences (P < .001). SNR increased 2.15-fold with WE-SHARP-DWI and 2.93-fold with WE-SHARP-DWI*. CNR also improved substantially with the WE-SHARP sequences (30.75 ± 36.83 and 42.43 ± 53.23 vs. 13.49 ± 14.39). Further, WE-SHARP sequences demonstrated lower ADC measurement variability with lower standard deviations (32.80 ± 19.13 × 10⁻³ mm²/s and 34.39 ± 18.22 × 10⁻³ mm²/s vs. 51.48 ± 17.89 × 10⁻³ mm²/s) in normal liver and more pronounced ADC differences between benign and malignant lesions (1179 × 10^⁻3 mm²/s and 1197 × 10^⁻3 mm²/s vs. 1009 × 10^⁻3 mm²/s.). The WE-SHARP-DWI techniques demonstrated improved diagnostic performance with higher sensitivity (0.95 vs. 0.88) and greater area under the ROC curve (0.98 vs. 0.95) compared with SPAIR-DWI.

Both WE-SHARP-DWI techniques demonstrated superior image quality and diagnostic value for assessing FLLs than the conventional SPAIR technique. These techniques retained clinically acceptable image quality even at high b values.