脑脊液~1H-MRS对线粒体脑病的诊断价值研究

Diagnostic value of cerebrospinal fluid ~1H-MRS for mitochondrial encephalopathy

目的探讨脑脊液~1H-MRS对线粒体脑病的诊断价值,为临床诊断提供新的线索和思路。材料与方法选取经线粒体脑肌病标准评分系统确诊的13例线粒体脑病(mitochondrial disorders,ME)患者及17例临床上疑似线粒体脑病但最终确诊非线粒体病的患者为对照组,所有患者行常规MRI和~1H-MRS检查,选取MRI异常信号区(脑内无明显病变者,选取左侧基底节区为感兴趣区)、正常脑组织区及脑脊液区为感兴趣区,分别比较两组患者相应区域乳酸(Lac)峰的差异。结果脑脊液区~1H-MRS显示,10例(10/13)ME脑脊液区可见Lac峰;3例(3/17)对照组脑脊液区见Lac峰。脑内病变区~1H-MRS显示,5例(5/12)线粒体脑病患者病变区可见Lac峰,7例(7/12)病变区未见Lac峰,无病变者左侧基底节区未见Lac峰;6例(6/16)对照组病变区可见异常升高的Lac峰。脑脊液区~1H-MRS出现Lac峰诊断线粒体脑病的灵敏度、正确指数、阳性似然比、阴性似然比、符合率均优于病灶区。联合脑脊液区与病灶区~1H-MRS诊断线粒体脑病分析,相比于单独脑脊液区~1H-MRS结果,串联试验的灵敏度降低,特异度升高;并联试验灵敏度不变,特异度降低。串联、并联试验的正确指数及符合率均低于脑脊液区。结论线粒体脑病NAA峰降低、Cho峰升高无特异性,与其它非线粒体脑病难以鉴别;脑脊液区~1H-MRS出现Lac峰对线粒体脑病的诊断价值优于脑内病变区,有助于对脑脊液乳酸水平的检测。

Objective： To investigate the diagnostic value of cerebrospinal fluid ^1H-MRS for mitochondrial encephalopathy and provide new clues and ideas for clinical diagnosis. Materials and Methods： Thirteen patients with mitochondrial encephalopathy（ME） and 17 patients with clinically suspected mitochondrial encephalopathy but ultimately diagnosed with non-mitochondrial disease were selected as control group. All patients underwent routine MRI and ^1H-MRS examination. The Lac peak were compared between the two groups of patients respectively. Results： Cerebrospinal fluid ^1H-MRS showed that 10 cases（10/13） of the cerebrospinal fluid area showed Lac peaks,3 cases（3/17） of the control group showed Lac peaks in the cerebrospinal fluid area. ^1H-MRS showed 5 cases（5/12） Lac peaks were observed in the lesion area of ME. Elevated Lac peaks were observed in the lesion area of the control group in 6 cases（6/16）. The sensitivity,correct index,positive likelihood ratio,negative likelihood ratio,and coincidence rate of lac peak in the diagnosis of mitochondrial encephalopathy in the ^1H-MRS in cerebrospinal fluid region were better than those in lesion area. Analysis of ^1H-MRS diagnosis of mitochondrial encephalopathy combined with cerebrospinal fluid area and lesion area showed that compared with ^1H-MRS results of cerebrospinal fluid alone,the sensitivity of the tandem test was reduced,and the specificity was increased. The correct index and coincidence rate of serial and parallel tests were lower than those in the cerebrospinal fluid region. Conclusions： The appearance of Lac peak in cerebrospinal fluid ^1H-MRS is superior to that in brain lesion area,which contributes to the lactate level detection in cerebrospinal fluid.