The Applications Of 3.0T ~1H-MRS On Grading Cerebral Gliomas

Objective: To investigate the value of 3T 1H-MRS on grading cerebral gliomas.Methods: 3.0 T magnetic resonance spectroscopy (MRS) was obtained in a total of 20 normal cases and 45 patients with cerebral gliomas ( grade one 6, grade two16, grade three 12, grade four 11). 45 cases of astrocytomas underwent routine MRI, and 1H-MRS spectroscopy examination. N-acetylaspartate(NAA),Choline(Cho),Creatine(Cr),Lactate(Lac) and myo-Inositol(mI) were measured in the regions of tumor,and corresponding normal brain. NAA/Cr,Cho/Cr and NAA/Cho ratios were obtained from both the regions of tumor and corresponding normal brain of each group and that of four grades.Results: We can observe the decreasing of NAA and increasing of Cho in the region of tumor. While Lac signal was detected in 23 patients and mI signal was detected in 30 patients, Lip signal was detected in 18 patients. In the regions of tumor, the NAA/Cr,NAA/Cho and Cho/Cr ratios changed significantly by comparing with that of normal control of brain tissue . Cho to Cr ratios of four grades were (1.44±0.15,1.85±0.35,2.81±0.22,4.38±0.39).A significant difference existed the Cho/Cr ratios in the region of tumor among the four group (P<0.05),but no significant different existed the NAA/Cr,NAA/Cho among II to IV groups (P >0.05).Conclusion: Each rank of astrocytoma has difference in various chemical composition content including NAA, Cho, Cr, Lac, Lip, mI etc. NAA/Cr,Cho/Cr and NAA/Cho ratios also exited difference among each rank of astrocytoma. Surveys and analyzes each chemical composition content and the ratio difference of various ranks can improve diagnostic accuracy of astrocytoma, and provides a helpful surgery plan and the choice of treating plan after surgery.