The Application Value Of Multi-parameter Magnetic Resonance Imaging In The Glioma And Its Correlation With Ki-67

BackgroundGliomas are the most common primary brain tumors in the central nervous system.According to the classification criteria of the central nervous system(CNS)of the WHO,the pathological features of gliomas are highly heterogeneous.Although the histopathology is the gold standard for the diagnosis of glioma,but because of the heterogeneity of the tumor,both surgical resection or stereotactic biopsy may lead to errors in sampling errors.MRI plays an important role in the diagnosis of glioma.Conventional MRI scan and contrast enhancement in the diagnosis of glioma,the tumor is generally considered to be malignant and benign.But this method has great limitations,because of high grade gliomas do not show enhancement,and some low grade gliomas but there will be enhanced,so the conventional MRI is very difficult to carry out accurate grading of glioma before operation.Functional MRI imaging can be used to evaluate glioma from the aspects of biochemical metabolism,diffusion and hemodynamics.The Ki-67 index as a tumor cell proliferation nuclear antigen in the immunohistochemical,its expression level represents the ability of tumor cells proliferate.According to the previous literature,with the increase of tumor grade,the expression of Ki-67 index increased gradually.Although there are many reports on the application of functional magnetic resonance imaging(DWI,DTI,MRS,etc.)in the brain glioma,however,there is relatively little research on the correlation between the quantitative parameters and the Ki-67 index.ObjectiveTo explore the application of multi-parameter magnetic resonance imaging in glioma and its correlation with Ki-67.MethodsCollected 31 patients with glioma proved by surgery and pathology in our hospital from March 2015 to March 2016 were analyzed retrospectively.According to the 2016 World Health Organization classification ang grading standard of tumors of the Central Nervous System(CNS),high-grade gliomas(?~?grade)18 cases and low-grade gliomas(? ~ ? grade)13 cases.All the patients had cerebral pre-contrast MRI images(AXT1WI/T2WI/FlairT2WI/DWI ? SagT1WI),enhanced-MRI images,multi-voxel MRS and DTI.Post-processing in the workstation and acquisition ADC image,FA image and DCavg image,3 ROIswere drawn on the solid component in different regions,and avoid cystic,necrosis,hemorrhage and calcification area,the range of ROI is about 28-38mm2,the lesions of the largest cross-sectional area as the center,continuous measurement of 3 layer,acquisition ADC value,DCavg value,FA value,and take the average value as the final value.acquisition the Cho/Cr value and Cho/NAA value were measured by enhancing the region or the real area in the enhanced multi-voxel MRS image,and the average value was taken as the final value.To obey the Gaussian distribution and homogeneity of variance measurement data using independent sample t test,if don't obey the Gaussian distribution of data,using independent samples nonparametric test(Mann-WhitneyU test)and Spearman rank correlation analysis,with P<0.05 as the difference was statistically significant.The MRI parameters of the ROC with statistical significance were analyzed to obtain the best diagnostic threshold,and the diagnostic sensitivity and specificity were obtained.ResultsHigh-grade gliomas were significantly enhanced,whereas low-grade gliomas were significantly enhanced in 1 cases,mild in 7,and not enhanced in 5.High-grade and low-grade gliomas of ADC values,Cho/Cr ratio,Cho/NAA ratio and Ki-67 index significant difference(P<0.05);There is no significant difference DCavg value and FA value(P > 0.05).Ki-67 and ADC value showed a negatively correlated(r=-0.442,P<0.05);Ki-67 and Cho/Cr,Cho/NAA values showed a positively correlated(r=0.596,r=0.448,P<0.05),but Ki-67 with DCavg(r=-0.101,P=0.589)and FA value(r=0.147,P=0.429)had no correlation.ADC 1.073x10-3mm2/s is the best diagnostic threshold,the sensitivity and specificity were 100%,94.4%;Cho/Cr 2.28 is the best diagnostic threshold,the sensitivity and specificity were 100%,92.3%;Cho/NAA 2.40 is the best diagnostic threshold,the sensitivity and specificity were 94.4% and 92.3%.ConclusionThe ADC values of DWI and MRS parameter Cho/Cr and Cho/NAA values can predict the grade of glioma and evaluate the proliferative activity of glioma.However,the DTI parameters were not effective in evaluating the grade of glioma,and there was no correlation between FA value,DCavg value and Ki-67.So multi-parameter magnetic resonance imaging not only help glioma preoperative grading,but also evaluate tumor cell proliferative activity,which has the more important clinical value.