The application value of diagnosis and differential diagnosis of magnetic resonance diffusion kurtosis imaging for fourth ventricle tumors

ZHAO Xiuyu; YU Jinfen; WANG Yu; ZHANG Haiqing; LI Chuanting

Abstract：Objective This study aimed to explore the application values of diffusion kurtosis imaging(DKI) in detecting in-ternal components and cell proliferation of fourth ventricle tumors and to analyse the correlation of the imaging parameters with Ki-67. Meanwhile,to explore the application values in differential diagnosis of medulloblastoma and ependymoma. Methods 21 pa-tients with the four ventricle tumor were examined preoperatively with conventional magnetic resonance imaging(MRI) and DKI, respectively. S-P inmmnohistechemical staining technique was used to detect the expression of Ki-67 in postoperative. The data of DKI were analyzed with diffusion kurtosis estimator(DKE) to calculate mean kurtosis(MK),radial kurtosi(Kr),axial kurtosis (Ka),mean diffusivity(MD) and fractional anisotropy(FA). Spearman correlation was used to analyze the correlation of the pa-rameter values and Ki-67. Independent-Samples T Test was used to analysis the differences of all the values in the two groups of tumor. The sensitivity and specificity of MK value, FA and MD values in differential diagnosis of two tumors were obtained by ROC curve analysis. Results The Ki-67 values of medulloblastoma were the highest in different types of tumors in the four ven-tricle region. The expression of Ki-67 showed positive correlation with MK value,with statistical significance( P <0.01). There was a significant difference between medulloblastoma and ependymoma in the values of MK,Ka,Kr and MD( P <0.01),while the FA value was not statistically significant( P >0.05). In the identification of medulloblastoma and ependymoma,the sensitiv-ity of MK value was 88.89%, the specificity was 87.50%, the AUC was 0.9722. The sensitivity of MD value was 77.78%,specificity was 87.50%,the AUC was 0.9028. The sensitivity and specificity of the FA value were respectively 66.67% and 62.50%, AUC was 0.6111. Conclusion Diffusion kurtosis imaging(DKI) can better detect cell proliferatione in fourth ventri-cle tumors.MK value could reflect Ki-67 expression level in the tumor and also has important value in differential diagnosis of the tumors.