Comparison of the Differential Diagnostic Performance of Intravoxel Incoherent Motion Imaging and Diffusion Kurtosis Imaging in Malignant and Benign Thyroid Nodules

OBJECTIVE: This study aimed to compare the diagnostic capacity between IVIM and DKI in differentiating malignant from benign thyroid nodules. MATERIAL AND METHODS: This study is based on magnetic resonance imaging data of the thyroid with histopathology as the reference standard. Spearman analysis was used to assess the relationship of IVIM-derived parameters D, f, D* and the DKI-derived parameters D(app) and K(app). The parameters of IVIM and DKI were compared between the malignant and benign groups. Binary logistic regression analysis was performed to establish the diagnostic model, and receiver operating characteristic (ROC) curve analysis was subsequently performed. The DeLong test was used to compare the diagnostic effectiveness of different prediction models. Spearman analysis was used to assess the relationship of Ki-67 expression and parameters of IVIM and DKI. RESULTS: Among the 93 nodules, 46 nodules were malignant, and 47 nodules were benign. The D(app) of DKI-derived parameter was related to the D (P < 0.001, r = 0.863) of IVIM-derived parameter. The K(app) of DKI-derived parameter was related to the D (P < 0.001, r = -0.831) of IVIM-derived parameters. The malignant group had a significantly lower D value (P < 0.001) and f value (P = 0.013) than the benign group. The malignant group had significantly higher K(app) and lower D(app) values (all P < 0.001). The D+f had an area under the curve (AUC) of 0.951. The D(app)+K(app) had an AUC of 0.943. The D+f+D(app)+K(app) had an AUC of 0.954. The DeLong test showed no statistical significance among there prediction models. The D (P = 0.007) of IVIM-derived parameters and D(app) (P = 0.045) of DKI-derived parameter were correlated to the Ki-67 expression. CONCLUSIONS: IVIM and DKI were alternative for each other in in differentiating malignant from benign thyroid nodules.