Differentiation between malignant and benign breast masses: combination of semi-quantitative analysis on DCE-MRI and histogram analysis of ADC maps.

AIM: To investigate the performance of combined semi-quantitative analysis on dynamic contrast enhanced (DCE) magnetic resonance imaging (MRI) and histogram analysis of diffusion-weighted imaging (DWI) for distinguishing malignant from benign breast masses. MATERIALS AND METHODS: This study included 178 patients with breast masses (benign:malignant=88:9) who underwent both DCE-MRI and DWI. The semi-quantitative parameters, derived from DCE-MRI, included maximum slope of increase (MSI), signal intensity slope (SIslope), initial percentage of enhancement (Einitial), percentage of peak enhancement (Epeak), early signal enhancement ratio (ESER), and second enhancement percentage (SEP). Histogram parameters derived from apparent diffusion coefficient (ADC) maps included ADCmin, ADCmax, ADCmean, ADC10, ADC25, ADC50, ADC75, ADC90, skewness, and kurtosis. All parameters were compared between malignant and benign groups, and their differences were tested using independent-samples t-test or Mann-Whitney test. Receiver operating characteristic (ROC) curves were used to determine the diagnostic value of each significant parameter. RESULTS: Among semi-quantitative parameters, SIslope exhibited the best diagnostic performance in predicting malignancy (cut-off value, 0.096; ROC, 0.756; sensitivity, 86.7%; specificity, 61.4%). Among histogram parameters, ADC10 exhibited the best diagnostic performance in predicting malignancy (cut-off value, 1.051; ROC, 0.885; sensitivity, 86.7%; specificity, 84.1%). The optimal diagnostic performance of combined ADC10 and SIslope (area under curve [AUC], 0.888; sensitivity, 82.2%; specificity, 95.5%) was significantly better than SIslope alone (p<0.001). Moreover, the combination showed higher AUC (0.888 versus 0.885) than ADC10 alone, but the difference was not statistically significant (p=0.914). CONCLUSION: SIslope and ADC10 are significant predictors for breast malignancy. The combination of DCE-MRI and DWI improves differentiating performance.

In the assessment of supratentorial glioma grade: the combined role of multivoxel proton MR spectroscopy and diffusion tensor imaging.

AIM: To detect a difference in the parameters derived from proton magnetic resonance spectroscopy ((1)H-MRS) and diffusion tensor imaging (DTI) between low-grade and high-grade gliomas, and to evaluate whether the combination of these two techniques can improve the diagnostic accuracy of conventional magnetic resonance imaging (MRI) in supratentorial glioma grading. MATERIALS AND METHODS: Thirty patients with histologically proved supratentorial brain gliomas (12 low grade, 18 high grade) were prospectively evaluated with contrast material-enhanced MRI, DTI, and multivoxel (1)H-MRS (135 ms echo time). The tumour grades determined using the three methods were then compared with those obtained at histopathology. Receiver operating characteristic (ROC) analyses were performed to determine the optimum thresholds for glioma grading. Independent sample t-test, Spearman's rank correlation, and the Fisher's exact test were also carried out for statistical analysis. p<0.05 was considered statistically significant. RESULTS: Statistically significant differences were found between the low-grade and high-grade gliomas for the choline (Cho)/creatine (Cr), N-acetylaspartate (NAA)/Cr, NAA/Cho ratio in the tumours (p<0.01), apparent diffusion coefficient (ADC) value (p<0.01), and fractional anisotropy (FA) value (p<0.05) in the tumours. The NAA/Cr and NAA/Cho ratios and the calculated ADC value significantly correlated with the histological grading of the gliomas (p<0.01). Using a threshold value of 0.66 for tumour NAA/Cr, 0.265 for NAA/Cho, 1118.1×10(-6) mm(2)/s for the calculated ADC value, corresponding to the maximum Youden index from the ROC curve of the above-selected parameters, the resultant sensitivities, specificities, positive predictive values (PPVs), negative predictive values (NPVs), and Kappa values were all higher and the fraction of misclassified tumour was lower when compared with conventional MRI. However, only NAA/Cho and ADC calculation contributed to the significant difference (p<0.01) in the assessment of glioma grade compared to conventional MRI alone, and the grading results of statistical tests comparing those two parameters were highly consistent (kappa value=0.798). CONCLUSION: Thresholds for NAA/Cho and calculated ADC values, corresponding to maximum Youden index from ROC curve analyses, helped to improve the accuracy of supratentorial glioma grading when compared with conventional MRI alone. In addition, a combination of NAA/Cho and ADC calculation were more useful together than each alone in a clinical setting to evaluate glioma grade preoperatively and provide a means for guiding treatment.

[Quantitative analysis of muscone in shexiang baoxin pills by gas chromatography].

By using benzene as the extraction solvent and the method of internal standard, Shexiang Baoxin Pills was directly analyzed for muscone by GC. The method showed very good stability and linearity. The rate of recovery was 101.4%.