Comparison Of MRS And DWI Differentiation Between High Grade Gliomas And Low Grade Gliomas

Background and Purpose:Glioma is one of the most lethal,neuro-epithelial cell tumor.Originating from the glial cell of the brain.Prognosis are depends on the grade of glioma.However management of the HGG and LGG are different,symptoms and appearances are can be similar signal intensity in the conventional MRI.Magnetic resonance imaging has revolutionized the diagnosis and post-treatment evaluation of gliomas.Magnetic resonance spectroscopy?MRS?detects the metabolic and histological markers of the brain tissue.Magnetic Resonance Diffusion Weighted Imaging?DWI?detects the microstructure and cellular structure of water protons in brain tissue.The purposes of this study assess the MRS,DWI techniques in differentiating between low and high-grade gliomas.To evaluate the sensitivity and specificity of the MRS,DWI and ADC value in grading gliomas before treatment.METHOD AND MATERIALS:We retrospectively analyzed 47 patients.The 28 patients were diagnosed with high-grade glioma,19 patients were diagnosed by low-grade gliomas evaluated by3.0 Tesla Siemens machines.All lesions were pathologically proven by biopsy and surgery.All patients underwent MRI dynamic contrast study,MRS and DWI scans before surgery,followed by measurement of Naa?N-acetylaspartate?,choline-containing compounds?Cho?,creatine-phosphocreatine complex?Cr?,Naa/Cr,Cho/Cr,Cho/Naa,and ADC?Apparent diffusion coefficient?value on the solid region of the tumor mass and contralateral region.Analysed by ROC curve,P values less than 0.05 were considered statistically significant.The SPSS statistical software 21.0 was used in this study.RESULT:In MR dynamic contrast study the most of the HGGs were demonstrated highly heterogeneous enhancement?P=.006?,and rim pattern enhancement?P=.039?.On MRS analysis HGG intratumoral area were generally had a low level of Naa?P=.0014?,high level of Cho/Cr?P=.000?,high level of the Cho/Naa?P=.003?than LGG patients.In intratumoral NAA sensitivity 78.9%,specificity 73.2%,Cut off value was 1.4500,AUC 0.791.The sensitivity and specificity of the Cho/Cr ratio was75.9%,77.8%,cut off value was 2.0650 and the AUC 0.833,In Cho/Naa sensitivity67.9%,specificity 73.7%,cut off value was 2.5000 and the AUC was 0.754.On ADC map the LGG patients had a higher ADC value than HGG patients?P=.000?.The sensitivity and specificity were 84.2%,82.1%specific,cut off value was1.419x10^-3mm²/s and the AUC was 0.882.CONCLUSION:1.MRI has a high advantage in identification of location,qualitative and morphological manifestations of the gliomas and,different grade of the gliomas have different imaging characteristics.2.MRS and DWI have high value in the identification of high-grade gliomas and low-grade gliomas.3.The MRS and DWI sequences are the effective addition of conventional sequences,to make the imaging physicians to be more confident in the identification of the high-grade and low grade of the gliomas.