The Differentiation Value Of Single Brain Metastases And High-grade Gliomas In MR Susceptibility-weighted Imaging(SWI) And Perfusion-weighted Imaging(PWI)

Objective： To study the MR findings of susceptibility-weightedimaging(SWI) and MR perfusion-weighted imaging(PWI) in single brainmetastases and high-grade gliomas and to explore the value of differentialdiagnosis between these two tumors.Materials and Methods：In the study，conventional MR imaging and SWI wereperformed preoperatively on a3.0T scanner(SIEMENS Verio3.0T) in35patients with single brain metastases and50patients with high-gradegliomas. Among these patients,18patients with single brain metastasesand25patients with high-grade gliomas who had undergone dynamicsusceptibility contrast-enhanced T2*-weighted perfusion MR imaging atthe same time were selected. The number of cases which were foundhemorrhage on the conventional MR imaging and SWI were counted，then thedetection rates on SWI and the conventional MR imaging were statisticallyanalyzed in two tumors，and the rates of these two tumors on SWI was alsostatistically analyzed. Furthermore, the quantity of hemorrhage and thenumber of the vein vessels in lesions of these two tumors on SWI werestatistically analyzed. On PWI, postprocessing was performed to generatecolor CBV maps. The maximal rCBV measurements were obtained from regionsof enhancing tumoral bodies and peritumoral regions and the correspondingopposite white matter respectively. At the same time, the relative peakheight of enhancing tumoural bodies and peritumoral regions and thepercentage of signal intensity recovery of enhancing tumoral bodies weremeasured from T2*time-signal-intensity curves. All these measurementswere statistically analyzed respectively.Results: We found a statistically significant difference(P<0.05) between the conventional MR imaging and SWI in the detection of hemorrhage in thesetwo tumors. There was not a statistically significant difference(P>0.05)between these two tumors on SWI in the hemorrhage rates of the tumors.On SWI,there was a statistically significant differences(P<0.05)in thenumber of the vein vessels in lesions between these two tumors. high-gradegliomas were more than that of single brain metastases. But,there was nota statistically significant difference(P>0.05) between these two tumorsin the quantity of hemorrhage. On PWI, the maximal rCBV of peritumoralregions in high-grade gliomas was found higher than that of single brainmetastases(P<0.05), but no found in the enhancing tumoral bodies betweentwo tumors(P>0.05). On TISC, the relative peak height of enhancing tumoralbodies and peritumoral regions and the percentage of signal intensityrecovery of enhancing tumoral bodies in high-grade gliomas were foundsignificantly statistically higher than that of single brainmetastases(P<0.05).Conclusion：SWI is more sensitive than the conventional MR imaging indetecting hemorrhage of high-grade gliomas and brain metastases.The twotumors are prone to hemorrhage.On SWI,the number of vein vessels inhigh-grade gliomas are higher than that of single brainmetastases.Together with the maximal rCBV of peritumoral regions ofhigh-grade gliomas, the relative peak height of enhancing tumoral bodiesand peritumoral regions and the percentage of signal intensity recoveryof enhancing tumoral bodies of high-grade gliomas are higher than thatof single brain metastases. Therefore, SWI and PWI can be helpful in thedifferentiation between single brain metastases and high-gradegliomas,but the role of the former is relatively limited.