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Objective@#To evaluate the value of MRI-T2WI texture analysis in the differentiation of atypical medulloblastoma and ependymoma of the fourth ventricle.@*Methods@#Preoperative MRI data of 36 cases of fourth ventricle tumor (19 cases of medulloblastoma and 17 cases of ependymoma) confirmed by the Central Theater General Hospital of the Chinese People′s Liberation Army were retrospectively analyzed. Manually sketch areas of interest (ROI) were made using texture analysis software to get histogram parameters, including mean, median, standard deviation, skewness, kurtosis, maximum, minimum, heterogeneity, entropy, the 5th percentile (T2WI5th), the 10th percentile (T2WI10th), the 25th percentile (T2WI25th), the 50th percentile (T2WI50th), the 75th percentile(T2WI75th), the 95th percentile(T2WI95th). Independent sample t test or mann-whitney U test was used for statistical analysis of each parameter value between the two groups. Logistic regression analysis was used to perform multiparameter joint analysis on meaningful parameters. The area under the curve (AUC) was obtained by using the subject operating characteristic (ROC) curve to determine the threshold and diagnostic efficacy for distinguishing the two group.@*Results@#The mean, median, T2WI5th, T2WI10th, T2WI25th, T2WI50th, T2WI75th values of the medulloblastoma group were smaller than those of the ependymoma group, and difference was statistically significant (P<0.05). The T2WI5th had the best diagnostic performance. When the critical value was 1 343, the diagnostic specificity was 75.0% and the sensitivity was 92.9%. Logistic regression was used to predict the joint analysis of probability parameters. T2WI5th+T2WI10th had the best performance, and AUC was 0.928. When the critical value was 0.75, the diagnostic specificity was 75.0% and the sensitivity was 100.0%.@*Conclusions@#MRI-T2WI texture analysis can provide quantitative information for preoperative diagnosis of atypical medulloblastoma and ependymoma and improve the accuracy of preoperative diagnosis, which has obvious clinical value.
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Objective To evaluate the value of MRI-T2WI texture analysis in the differentiation of atypical medulloblastoma and ependymoma of the fourth ventricle.Methods Preoperative MRI data of 36 cases of fourth ventricle tumor (19 cases of medulloblastoma and 17 cases of ependymoma) confirmed by the Central Theater General Hospital of the Chinese People's Liberation Army were retrospectively analyzed.Manually sketch areas of interest (ROI) were made using texture analysis software to get histogram parameters,including mean,median,standard deviation,skewness,kurtosis,maximum,minimum,heterogeneity,entropy,the 5th percentile (T2WI5th),the 10th percentile (T2WI10th),the 25th percentile (T2WI25th),the 50th percentile (T2WI50th),the 75th percentile(T2WI75th),the 95th percentile (T2WI95th).Independent sample t test or mann-whitney U test was used for statistical analysis of each parameter value between the two groups.Logistic regression analysis was used to perform multiparameter joint analysis on meaningful parameters.The area under the curve (AUC) was obtained by using the subject operating characteristic (ROC) curve to determine the threshold and diagnostic efficacy for distinguishing the two group.Results The mean,median,T2WI5th,T2W10th,T2WI25th,T2WI50th,T2WI75th values of the medulloblastoma group were smaller than those of the ependymoma group,and difference was statistically significant (P ＜ 0.05).The T2WI5th had the best diagnostic performance.When the critical value was 1 343,the diagnostic specificity was 75.0％ and the sensitivity was 92.9％.Logistic regression was used to predict the joint analysis of probability parameters.T2WI15th+T2WI10th had the best performance,and AUC was 0.928.When the critical value was 0.75,the diagnostic specificity was 75.0％ and the sensitivity was 100.0％.Conclusions MRI-T2WI texture analysis can provide quantitative information for preoperative diagnosis of atypical medulloblastoma and ependymoma and improve the accuracy of preoperative diagnosis,which has obvious clinical value.
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Objective To compare the diagnostic value of CT and diffusion-weighted imaging in extremity soft tissue tumors. Methods A total of 104 cases of extremity soft tissue tumors were examined with CT scanning and MRI. All cases were histologically proven. Then we compared the CT value of various types of tumors. The b values of diffusion were 0 and 500 s/mm2. The apparent diffusion coefficient (ADC) values of a large region with no hemorrhage, necrosis, scar tissue, or calcification representing the lesion were measured. ADC values of benign tumors, malignant tumors and normal muscles were compared. Results There were 68 cases of benign tumors and 36 cases of malignant tumors. The CT findings of 45 cases and the MRI findings of 87cases were in accordance with pathological examination. The diagnosis of 59 cases by CT and 17 cases by MRI were wrong. The CT features of soft tissue tumors showed the low density masses. The features of lipoma or cyst were typical on CT. There were large differences among the different types of tumors performance on T1WI and T2WI. The ADC values of the malignant tumors were significantly lower than those of benign lesion sand muscles (P < 0.01). There was no significant difference in ADC values between benign lesions and muscles. there was significant difference between the detection level of CT and MRI (P < 0.01). Conclusion CT can clearly show soft tissue tumor lesions and to clarify their relationship and the surrounding tissue, but can not accurately characterize. MRI diffusion-weighted imaging can better differentiate benign and malignant, and speculate the histological lesions sources. MRI detection level is significantly higher than CT and more consistent with a higher degree of pathology. Thus in the preoperative diagnosis of soft tissue tumors, diffusion-weighted imaging MRI should be preferred.