~1H-MRS在原发性中枢神经系统淋巴瘤与高级别胶质瘤鉴别诊断中的价值

The Clinical Value of ^1H-MRS in Differentiating Primary Central Nervous System Lymphoma from High Grade Gliomas

目的探讨单体素不同回波时间(TE=30 ms/135 ms)和多体素长回波(TE=135 ms)MRS在原发性神经系统淋巴瘤(PCNSL)与高级别胶质瘤(HGG)鉴别诊断中的价值。方法回顾性分析19例PCNSL(13例经病理证实,6例经诊断性治疗确诊)和22例HGG(均经病理证实)患者影像资料。19例PCNSL均行单体素短和长回波MRS检查,其中15例行多体素长回波MRS检查。22例HGG均行单体素短和长回波MRS及多体素长回波MRS检查。分析不同TE时间单体素MRS在瘤体中的不同代谢物相对比值,同时分析多体素长回波MRS在瘤体及瘤周中的不同代谢物相对比值。结果单体素短回波MRS的Cho/Cr和NAA/Cr在PCNSL与HGG的鉴别诊断中差异均有统计学意义(P<0.05);Cho/NAA和(Lac+Lip)/Cr在两者的鉴别诊断中差异均无统计学意义(P>0.05)。单体素长回波MRS的Cho/Cr、NAA/Cr和Cho/NAA在两者的鉴别诊断中差异均有统计学意义(P<0.05)。多体素长回波MRS瘤体的Cho/Cr、NAA/Cr和Cho/NAA在两者的鉴别诊断中差异均无统计学意义(P>0.05);瘤周的Cho/Cr、NAA/Cr和Cho/NAA在两者的鉴别诊断中差异均无统计学意义(P>0.05)。结论单体素MRS代谢物是鉴别诊断PCNSL与HGG的有效指标,多体素长回波MRS鉴别诊断价值有限。

Objective To evaluate the single voxel different echo time（ TE = 30 /135ms） and multi voxel long echo time（ TE = 135ms） MRS in differentiating primary central nervous system lymphoma（ PCNSL） from high grade gliomas（ HGG）. Methods The imaging materials of 19 patients with PCNSL（ pathologically-confirmed in 13 and diagnostic treatment-confirmed in 6） and 22 patients with pathologically-proved HGG were retrospectively analyzed. Single voxel short and long echo time MRS examination was employed in 19 patients with PCNSL,in whom additional multi voxel long echo time MRS examination was also adopted in 15. Single voxel short and long echo time MRS and multi voxel long echo time MRS examination were carried out in all the 22 patients with HGG. The relative ratios of different metabolites in the core of tumor obtained by different echo time single voxel MRS were analyzed,and the relative ratios of different metabolites in the tumor and the peritumoral region obtained by multi voxel long echo time MRS were also analyzed. Results The ratios of Cho / Cr and NAA / Cr obtained by single voxel short echo time MRS had statistical significance in the differential diagnosis of PCNSL with HGG（ P〈0. 05）,while the ratios of Cho / NAA and Lac ＋ Lip / Cr had no statistical significance in differentiating PCNSL from HGG（ P〉0. 05）. The ratios of Cho / Cr,NAA / Cr and Cho / NAA determined by single voxel long echo time MRS MRS had statistical significance in the differential diagnosis of PCNSL with HGG（ P〈0. 05）,while the ratios of Cho / Cr,NAA / Cr and Cho / NAA determined by multi voxel long echo MRS had no statistical significance in differentiating PCNSL from HGG（ P〉0. 05）. The ratios of Cho / Cr,NAA / Cr and Cho / NAA in peritumoral region had no statistical significance in differentiating PCNSL from HGG（ P〉0. 05）. Conclusion Single voxel MRS metabolite is an effective index for the differential diagnosis of PCNSL and HGG,multi voxel long echo MRS has limited value in differentiation.