Differential Diagnosis Of Benign And Malignant Meningiomas By ASL And DCE Perfusion MRI

Objective:To evaluate the value of arterial spin labeling(ASL)and dynamic contrast enhanced(DCE)perfusion magnetic resonance imaging(MRI)in the differential diagnosis of benign and malignant meningiomas.Methods:In this study,ASL and DCE scanning were performed in patients with suspected meningiomas.Finally,43 patients with meningioma confirmed by pathology after operation were collected,including 36 cases of benign meningiomas(3 cases of angiomatous meningiomas and 33 cases of benign non-angiomatous meningiomas)and 7 cases of malignant meningiomas.Measurement of kinetic parameters of ASL:ROIs were placed in the solid components of tumor,peritumor edema area and contralateral gray matter to measure the maximum and mean cerebral blood flow(CBF)values of the meningioma(CBFmax,CBFmean),the CBF values of peritumor edema area(CBFpte)and contralateral gray matter(CBFgm).And the relative CBF values(rCBFmax,rCBFmean,rCBFpte)were calculated.Measurement of kinetic parameters of DCE:ROIs were placed in the solid components of tumor to measure the maximum and mean values of volume transfer constant(Ktrans max,Ktrans mean)extravascular-extracellular space volume fraction(Vemax,Vemean),plasma volume fraction(Vpmax,Vpmean),and initial area under concentration time curve(IAUCmax,IAUCmean).The results were analyzed by Kruskal-Wallis H test and Mann-Whitney U test.The diagnostic efficacy of parameters with statistical significance were evaculated by receiver operating characteristic(ROC)curves.Spearman rank correlation analysis was performed for ASL parameters and DCE parameters measured by the same ROI in the solid components of tumor.Results:The values of CBFmax,CBFmean,rCBFmax,rCBFmean,Ktransmax,Ktransmean Vpmax,Vpmean,IAUCmax and IAUCmean of benign non-angiomatous meningiomas were significantly lower than that of angiomatous/malignant meningiomas.ROC curve analysis demonstrated that rCBFmax had the hightest diagnostic efficiency.When the cut-off points were 3.666,the specificity and sensitivity of distinguishing benign non-angiomatous meningiomas and angiomatous/malignant meningiomas were 100%.The values of CBFpte and rCBFpte in PTE areas of malignant meningiomas were significantly higher than that of benign meningiomas(including angiomatous and non-angiomatous types).ROC curve showed that CBFpte had the hightest diagnostic efficiency.When hen the cut-off point was 19.74 ml/min/100g,the specificity and sensitivity of distinguishing malignant and benign meningiomas were 89.5%and 100%respectively.The absolute/relative CBF values were positively correlated with Ktrans,Vp and IAUC values measured by the same ROI in the solid components of tumor.Conclusion:Combining ASL kinetic parameters of the solid components of tumor(CBFmax?CBFmean?rCBFmax?rCBFmean)and peritumoral edema(CBFpte?rCBFpte),we can differentiate hemangiomas,benign non-angiomatous meningiomas and malignant meningiomas.The DCE kinetic parameters of the solid components of tumor(Krans smax,Ktransmean,Vpmax,Vpmean,IAUCmax,IAUCmean),although not as effective as ASL-MRI,can also be useful in differentiating benign non-angiomatous meningiomas from vascular/malignant meningiomas.