Objective To study the application of magnetic resonance (MR) perfusion-weighted imaging (PWI) and diffusion tensor imaging (DTI) in grading of gliomas.
Methods MRI diffusion tensor imaging (DTI) and perfusion weighted imaging (PWI) were performed in 78 cases of cerebral gliomas (35 low-grade and 43 high-grade ghomas) in our hospital.The average apparent diffusion coefficient (ADC),fractional anisotropy (FA),relative ADC (rADC),relative FA (rFA),relative cerebral blood flow (rCBF),relative cerebra blood volume (rCBV),relative regional cerebral blood flow (rrCBF),relative regional cerebra blood volume (rrCBV) of peritumoral regions and analogous locations in the contralateral white matter (WM) corresponding to the tumor were measured on corresponding parameter maps generated from DTI or PWI.SPSS was used in comparative study on differentiation among different area and different grading of gliomas.Receiver operating characteristic (ROC) analyses was also conducted to explore optimum thresholds for tumor grading.The sensitivity and specificity were also discussed.
Results ADC,rCBF and rCBV values of tumor were greater than those of the peritumoral regions tissues and contralateral white matter;FA of tumors was less than that of the peritumoral regions tissues and contralateral white matter,the differences had statistical significance (
P<0.05);rrCBV and rrCBF in the high-grade glioma tumors and peficancerous tissues were higher than those in the low-grade glioma,respectively (
P<0.05),however,rADC value was lower than that in the low-grade glioma (
P<0.05);According to the ROC curve analysis,rrCBF and rrCBV area under the curve were 95.4% and 90.2%,the sensitivity and specificity for tumor grading were 87.0%,95.2% and 85.3%,89.2%,respectively.
Conclusion Magnetic resonance PWI and DTI can be used for preoperative grading of glioma,and rrCBF is one of the important indicators for the diagnosis of cerebral gliomas.
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