Dynamic Susceptibility Contrast-enhanced Perfusion And Diffusion-weighted Imaging In The Diagnosis Of Glioma

Dynamic Susceptibility Contrast-enhanc ed Perfusion in thegrading of gliomaObjective:To assess the diagnostic accuracy of cerebral blood volume (CBV) and bloodflow (CBF) values derived from dynamic susceptibility-weighted contrast-enhancedperfusion MR imaging (DSC-MR imaging) for grading of cerebral glial tumors。Methods:A total of52patients with cerebral glial tumors underwent DSC-MR imaging ata clinical3.0T imaging unit. According to the WHO classification standard, grade Ⅰand grade Ⅱ was classified as low-level, grade Ⅲ and grade Ⅳ was classified ashigh-level. The present study included30cases of high-grade tumors,22cases oflow-grade tumors. Normalized relative CBV (rCBV) and relative CBF (rCBF) fromtumoral (rCBVt, rCBF), peri-enhancing region (rCBVe, rCBFe) werecalculated.Receiver operating characteristic (ROC) curve analyses were alsoperformed for each of the variables.Results:The differences in rCBV and rCBF values between high and low grade gliomawere statistically significant. According to ROC analyses for distinguishing tumorgrade, rCBVt showed the largest areas under ROC curve (AUC).Conclusion:DSC is a suitable method for assessment of tumors microvascular perfusion andallows distinction between high and low grade glioma. Both rCBVt and rCBFtshowed good discriminative power in distinguishing between high and low gradeglioma. However，rCBVt is associated strongly with tumor grade. Dynamic Susceptibility Contrast-enhanced Perfusion in thedifferentiation diagnosis between high gliomas andmetastasisObjective:To investigate the value of cerebral blood volume (CBV) and blood flow (CBF)in the distinction of metastasis from high grade glioma using dynamicsusceptibility-weighted contrast-enhanced perfusion MR imaging (DSC-MRI) and toestimate the diagnostic accuracy of perfusion MR imaging.Method:A prospective study of50patients (30high grade gliomas and20metastases)was performed at3T using DSC-MRI. The rCBV and rCBF values were normalizedto rCBV and rCBF values of the contralateral normal white matter. Normalized rCBVand rCBF from tumoral (rCBVt, rCBFt), peri-enhancing region (rCBVe, rCBFe) werecalculated.Results:The rCBVe, rCBFe were significantly greater in high grade glioma comparedwith those of metastases. The optimal cutoff value for differentiating GBM frommetastasis was0.98which implies a sensitivity of89.3%, a specificity of70%, apositive predictive value of88.9%, and a negative predictive value of66.7%forrCBVe ratio.Conclusion:Statistically, both rCBVe and rCBFe were useful in differentiating between highgrade glioma and metastases, supporting the hypothesis that perfusion MR imagingcan detect infiltration of tumor cells in the peri-enhancing region. Corelation between ADC and Ki-67in the diagnosis ofgliomaObjective:The purpose of this study was to determine the correlation between Ki-67andapparent diffusion coefficient (ADC) in gliomas.Method:A retrospective analysis of the advanced imaging and immunohistochemicalcharacteristics of52patients with high and low glioma was performed.The relativeminimum ADC and specimen Ki-67index were measured. Pearson’s correlation wasused to compare these parameters.Results:The average Ki-67between high and low grade gliomas was40.25±15.17(range,15–67%)and4.95±2.41%(range,2–10%), respectively. The mean minimum ADCratio was1.36(SD,0.22) and was1.96(SD,0.59). There was a significant negativecorrelation between minimum ADC and Ki-67(Pearson’s correlation, r=-0.552; p<0.01).Conclusion:The minimum ADC value can indirectly reflect the proliferation and malignancyof glioma.