Comparison of conventional diffusion-weighted imaging, diffusion kurtosis imaging and intravoxel incoherent motion in characterization of sonographically indeterminate adnexal masses

To evaluate the role of conventional diffusion weighted imaging, diffusion kurtosis imaging (DKI), and intravoxel incoherent motion (IVIM) in distinguishing benign from malignant adnexal masses.

38 patients with 45 adnexal masses were enrolled in this prospective study and assessed with multiparametric MRI, including the IVIM-DKI sequence, on a 3 T MRI system. The mean apparent diffusion coefficient (ADC) from conventional DWI, the apparent diffusion coefficient derived from DKI (D_app), the apparent kurtosis coefficient (K_app), true diffusion coefficient (D_t), perfusion fraction (f) and pseudo-diffusion coefficient (D_p) were measured.

The mean ADC, D_app, and D_t were significantly higher in benign adnexal masses than in malignant adnexal masses (p < 0.001). f and D_p were also significantly higher in benign adnexal masses, with p values of 0.026 and 0.002, respectively. K_app was higher in malignant masses (p < 0.001). Among mean ADC, D_app, and D_t, mean ADC had the highest area under the curve (AUC) of 0.885. However, no statistically significant differences were observed between the ROCs of various diffusion parameters.

The mean ADC, D_app, and K_app are useful parameters in discriminating between benign and malignant adnexal masses. D_t derived from IVIM also helps in distinguishing benign and malignant adnexal masses; however, no incremental role of IVIM and DKI over ADC could be identified in our study.