Evaluation Of Brian Glioma Grading And Brain Tumor Diagnosing With Dynamic Susceptibility-contrast MR Imaging

Objective To investigate the value of dynamic susceptibility-contrast (DSC) MR imaging in grading astrocytomas and diagnosing different brain tumors.Materials and Methods DSC,conventional MR and enhanced scan were performed in 40 patients before surgery with histologically verified brian tumors(11 cases of low grade gliomas, 14 cases of high grade gliomas,7 cases of meningiomas,8 cases of metastases).Regional cerebral blood volume (rCBV) maps and perfusion curves were got from DSC, the maximum values of the toumor and peritumoral edema were measured, the data of low grade gliomas and high grade gliomas was analyzed with two independent samples rank sum test.Analyze the characteristic curve of different levels of astrocytomas; the data of high grade gliomas,meningiomas and metastasea was analyzed with multiple samples Kruskal-Wallis test; the maximum values of the peritumoral edema of high grade gliomas and meningiomas were also measured and the data was analyzed with two independent samples rank sum test; Analyze the characteristic curves of different tumors.Results (1)the rCBV maps and the perfusion cures in high and low grade astrocytomas have significant differences.the maximum rCBV values(compared with the contralateral normal brian) of the toumor in low (11cases) and high(14 cases) grade astrocytomas were 1.912±1.774,and 4.593±2.147 respectively,the maximum rCBV in low astrocytomas were significantly lower than high grade astrocytoma(st=-3.338,P<0.05);the maximum rCBV values of the peritumoral edema in low and high grade astrocytomas were0.461±0.375 and 0.740±0.218 respectively,the maximum rCBV in high were significantly higher than low grade astrocytomas(t=-2.208,P<0.05).(2)The largest decrease in perfusion signal curve in the toumor of low-grade astrocytomas was similar to or sligtly higher than the contralateral normal brian white matter;while, in the peritumoral edema,it was sligtly lower.The largest decrease in the toumor of high-grade astrocytomas was almost higher than the contralateral normal brian gray matter;while, in the peritumoral edema,it was higher than the contralateral normal brian white matter. (3)the maximum values of high gliomas,meningiomas,metastases were 4.593±2.147,9.484±2.634,5.331±2.320;There are significant difference between meningiomas and high gliomas or metastases,but there is no significant difference between high gliomas and metastases.(4)the maximum values of the peritumoral edema of high grade gliomas and metastases were 0.740±0.218,0.267±0.185, there is significant difference between the two tumors.(5)meningiomas are extra-axial tumors,they disply high perfusion,the intensity-time cure could not return to baseline level.Conclusion The DSC can reflect the blood micro-circulation and distibtion,so,it is very important for astrocytomas grading. it is useful for different brain tumors diagnosis.