三叉神经痛患者与健康志愿者丘脑1^H-MRS的比较

Comparison of 1^H MR Spectroscopic Findings of Thalamus in Trigeminal Neuralgia Patients and Healthy Volunteers

目的:比较三叉神经痛患者(TN)与健康志愿者丘脑的MRS表现,探讨三叉神经痛患者丘脑的生化和代谢变化。方法:TN患者和健康志愿者各10例,采用1.5TMR机行常规MRI(T1WI,T2WI和FLAIR序列)及单体素ProbeMRS检查。所有受试者经排除中枢神经系统结构性异常后,对其双侧丘脑的波谱数据经基线和相位校正后测量并计算NAA/Cr、Cho/Cr、mI/Cr和Glx值,对两组间的测量数据进行配对t检验,并与其McGill疼痛评估(MPQ)参数进行相关性分析。结果:健康志愿者丘脑的NAA/Cr值为1.87±0.23,TN患者为1.42±0.30,差异有极显著性意义(t=4.335,P=0.002);TN患者NAA/Cr的下降与其发病时间和MPQ中的心理情绪指标呈轻度相关。TN患者Cho/Cr和mI/Cr与对照组间的差异无显著性意义。TN患者丘脑区Glx峰升高,其对TN的诊断敏感度为70%,特异度为80%。结论:MRS检查显示TN患者丘脑NAA/Cr下降,Glx峰升高,提示TN患者丘脑活动失衡。1H-MRS可作为临床评价TN患者丘脑神经元功能活动的无创性检查方法。

Objective：To compare the MR spectroscopy manifestations of trigeminal neuralgia patients and healthy volunteers （for control subjects）,in order to study the biochemistry and metabolic changes in the thalamus of trigeminal neuralgia patients. Methods：Routine MRI including T1WI,T2WI and FLAIR sequences and single-voxel proton MRS （1^H-MRS） were performed in 10 trigeminal neuralgia patients and 10 healthy volunteers with 1.5 MR system. Pain indexes of 10 trigeminal neuralgia patients were scored using the short form McGill pain questionnaires. After structural abnormalities of brain was excluded,the NAA/Cr.Cho/Cr.mI/Cr ratio of bilateral thalami were calculated after spectral baseline and phase calibrations,and the paired t-test of spectral data of 10 trigeminal neuralgia patients and 10 healthy control subjects were performed with the SPSS statistics package. The changes of NAA/Cr,Cho/Cr and mI/Cr were analyzed to correlate with the pain indexes of 10 TN patients. Results：The ratio of NAA/Cr in the thalami was 1.87±0.23 and 1.42±0.30 in the control group and in TN patients respectively, with significant statistical difference （t（9） = 4. 335, P= 0. 002）. Decrease of NAA/Cr seemed to be correlated mildly with the duration of pain and the MPQ-affective index. No significant difference was existed for Cho/Cr and mI/Cr in the TN patients and controls. Compared to the controls,a marked increase in the Glx （Gln＆Glu） signal intensity was noted in the thalami of TN patients, and the sensitivity and specificity for the diagnosis of TN were 70% and 80% respectively. Conclusion：The present 1^H MRS study showed that marked decrease of NAA/Cr,increase of Glx in the thalami of TN patients,indicating abnormal proton metabolic changes of thalami. In vivo 1^H-MRS may serve as a useful noninvasive modality for evaluating thalamic neural activity in TN patients.