Use of monoexponential diffusion-weighted imaging and diffusion kurtosis imaging and dynamic contrast-enhanced-MRI for the differentiation of spinal tumors.

Abstract

To explore the diagnostic value of monoexponential diffusion-weighted imaging (DWI), diffusion kurtosis imaging (DKI), and dynamic contrast-enhanced (DCE)-MRI for differentiating between spinal malignant and non-malignant tumors lacking typical imaging signs and correlation between the parameters of the three models. DWI, DKI, and DCE-MRI examinations were performed in 39 and 27 cases of spinal malignant and non-malignant tumors, respectively. Two radiologists independently evaluated apparent diffusion coefficient (ADC), mean diffusivity (MD), and mean kurtosis (MK) of the DWI and DKI models, and volume transfer constant (K^trans), rate constant (k_ep), and extracellular extravascular volume ratio (v_e) of the DCE-MRI model for post-processing analyses. Statistical differences of parameters were compared using an independent sample t test. The sensitivity, specificity, and the area under the receiver operating characteristic (ROC) curve were determined. Pearson correlation analysis was used to evaluate the correlation between these parameters. ADC, MD, and v_e were significantly lower, while MK and k_ep were significantly higher for spinal malignant tumors than for non-malignant tumors. The MK had the highest area under the ROC curve of 0.940 and sensitivity (96.3%). V_e was weakly positively correlated with ADC (r = 0.468) and MD (r = 0.363) and weakly negatively correlated with MK (r = -0.469). k_ep was weakly positively correlated with MK (r = 0.375). K^trans was weakly positively correlated with ADC (r = 0.325). Monoexponential DWI, DKI, and DCE-MRI have potential value in the differentiation of spinal malignant from non-malignant tumors lacking typical imaging signs, and there is a certain correlation between the parameters of the three models. These slides can be retrieved under Electronic Supplementary Material.