ABSTRACT
Objective To evaluate the diagnostic efficacy of mDIXON Quant for vertebral metastasis. Methods We retrospectively analyzed MRI images of 152 patients with clinically diagnosed malignant tumors and vertebral metastases. Scanning sequence included T1WI, STIR, mDIXON Quant and enhanced T1WI. We compared the diagnostic efficiency between T1WI and FF images for vertebral metastases. FF values between normal vertebral body and vertebral metastases were quantitatively compared, and the diagnostic efficacy of FF value was evaluated by ROC curve. Results The sensitivity, false positive rate, false negative rate, negative predictive value and accuracy of FF images in the diagnosis of vertebral metastases were all higher than those of T1WI images. The FF value of vertebral metastasis was significantly lower than that of normal vertebral body (Z=-21.792, P < 0.05), and the area under ROC curve was 0.987 and the cutoff value was 9.87%. The diagnostic sensitivity and specificity of vertebral metastasis were 99.6% and 92.0%. Conclusion mDIXON Quant can quantitatively determine the fat content of vertebral metastasis and has a high diagnostic efficiency for vertebral metastases.
ABSTRACT
Objective:To evaluate the value of synthetic MRI combined with DWI in the diagnosis of benign and malignant breast lesions.Methods:The data of 184 consecutive patients with suspected breast lesions in Yunnan Cancer Hospital from July to September 2019 were prospectively analyzed. All patients were randomly assigned to training group ( n=110) and validation group ( n=74), and underwent conventional MRI and synthetic MRI respectively before and after contrast injection. At the maximum slice of the lesion, the ROI was drawn along the edge and recorded as "tumor". In the solid area with the most obvious tumor enhancement, the second ROI was drawn and recorded as "local". At the same time, ADC values (ADC local and ADC tumor) and relaxation time values (T local and T tumor) were measured. T and T + represented the relaxation time value of the ROI pre-and post-contrast scanning. ΔT% represented the relative change rate in T value between pre-and post-contrast scanning.The rank sum test was used to test the quantitative parameters of benign and malignant breast lesions in the training group and the validation group, and the variables with P<0.05 were included in the binary logistic regression analysis to screen the independent variables and establish the prediction model. The area under ROC curve was used to evaluate the discrimination of parameters and models. The clinical applicability of model was analyzed by decision curve analysis (DCA). Results:In the training group, univariate analysis showed that there were significant differences in T 1tumor, T 1+tumor, ΔT 1% tumor, T 2local, T 2+local, T 2tumor and T 2+tumor, ADC local, ADC tumor between benign and malignant breast lesions ( P<0.05). Multivariate logistic regression analysis showed that T 1+tumor, ΔT 1% tumor, T 2tumor, ADC local, ADC tumor were independent variables in the diagnosis of breast cancer. The relaxation time model (model A: T 1+tumor, ΔT 1% tumor, T 2tumor) and ADC model (model B: ADC local, ADC tumor) established by combining the above variables had the same diagnostic efficiency (AUC=0.905, 0.914, Z=-1.874, P=0.062), and the multi-parameter combination model (model C: T 1+tumor, ΔT 1% tumor, T 2tumor, ADC local, ADC tumor) had the highest diagnostic efficiency (AUC=0.965). DCA analysis showed that when the threshold probability ranges between 21%-99% (training cohort) and 15%-99% (validation cohort), the net benefit of model C was better than model A and B. Conclusion:The multi-parameter combined prediction model established based on the relaxation time value and ADC can identify breast cancer efficiently and can be used as an auxiliary diagnostic tool.
ABSTRACT
Objective To investigate the MRI features and characteristics of irregular intraductal papilloma (IDP)and invasive ductal carcinoma (IDC),and to improve the diagnostic accuracy of MRI.Methods This study retrospectively included 3 3 patients with IDP and IDC confirmed by surgery and pathology,and analyzed MRI findings including lesion size,boundary,internal components,plain signal intensity,enhancement mode,ADC value and TIC curve χ.2 test,t test and rank-sum test were performed.Results Compared with the two groups,lesion boundary (P＜0.001),size (P＜0.001 ),ADC value (P＜0.001 ),enhancement mode (P＝0.001 ),TIC curve peak time (P＜0.001),slope (P＜0.001)and peak enhancement rate (P＜0.001)were statistically significant (P＜0.05);lesion (P＝0.159), internal components (P＝0.778),T2 WI signal (P＝0.438)and curve type (P＝0.406)were no statistically difference.Conclusion The irregular mass type IDP and IDC have similar MRI findings,the edge of the lesion,the ADC value,the enhancement mode,and the peak time,slope and peak enhancement rate of the curve are important for the identification of the two diseases.