Proton spectroscopy of the thalamus in a homogeneous sample of patients with easy-to-control juvenile myoclonic epilepsy

Abstract Objective: Juvenile myoclonic epilepsy (JME) is a subtype of genetically determined generalized epilepsy that does not present abnormalities on conventional magnetic resonance imaging. The aim of this study was to identify metabolic alterations in the thalamus in a clinically homogeneous sample of patients with easy-to-control JME, using short-echo time proton magnetic resonance spectroscopy (MRS). Materials and Methods: We performed single-voxel (2 cm × 2 cm × 2 cm), short-echo time (TE = 35 ms) proton MRS of the thalamus in 21 patients with JME and in 14 healthy age-matched controls. We quantified N-acetylaspartate (NAA), total NAA, creatine (Cr), choline, and myo-inositol (MI), as well as the sum of glutamate and glutamine signals, all scaled to internal water content, and we calculated metabolite ratios using Cr as a reference. Values of p < 0.05 were considered significant. Results: The MI level and the MI/Cr ratio were significantly lower in the thalami of patients diagnosed with JME than in those of the controls. Other metabolites and their ratios did not differ significantly between the two groups. Conclusion: In our sample of 21 JME patients, we identified lower levels of MI in the thalamus. No significant abnormalities were observed in the concentrations or ratios of other metabolites.

目的：青少年肌阵挛性癫痫（Juvenile myoclonic epilepsy, JME）是遗传性全面性癫痫的一个亚型，常规磁共振成像无法检测到其异常表现。本研究旨在利用短回波时间质子磁共振波谱（short-echo time proton magnetic resonance spectroscopy, MRS），在临床特征均一、癫痫易于控制的JME患者样本中，分析丘脑的代谢改变。
材料与方法：本研究对21例JME患者及14例年龄匹配的健康对照者的丘脑进行单体素（2 cm × 2 cm × 2 cm）、短回波时间（TE = 35 ms）质子磁共振波谱扫描。我们对N-乙酰天冬氨酸（N-acetylaspartate, NAA）、总NAA、肌酸（creatine, Cr）、胆碱、肌醇（myo-inositol, MI）以及谷氨酸与谷氨酰胺的信号总和进行定量分析，所有指标均以内部水含量作为校准基准，并以Cr为参照计算代谢物比值。以p < 0.05为差异具有统计学意义。
结果：JME患者丘脑的肌醇水平及肌醇/肌酸比值显著低于对照组。其余代谢物及其比值在两组间均无显著差异。
结论：在本研究纳入的21例JME患者样本中，我们发现丘脑内肌醇水平降低。其余代谢物的浓度及比值均未出现显著异常。