Duncan J S
Epilepsy Research Group, Institute of Neurology, London, England, U.K.
Epilepsia. 1996 Jul;37(7):598-605. doi: 10.1111/j.1528-1157.1996.tb00622.x.
Magnetic resonance spectroscopy (MRS) is noninvasive and may be readily combined with magnetic resonance imaging (MRI). Attention has focussed on proton (1H) and phosphorus (31P) MRS, and studies have been undertaken by using single voxels or many voxels simultaneously (chemical-shift imaging, magnetic resonance spectroscopic imaging). The latter is more difficult and prone to artefact but potentially yields significantly more information. 1H MRS has principally yielded data on concentrations of N-acetyl aspartate (NAA), choline, creatine, and phosphocreatine. NAA is located primarily within neurons, and reduction of the ratio of NAA to choline, creatine, and phosphocreatine is a marker of neuronal loss and dysfunction. This technique may be useful as a noninvasive tool for localizing epileptogenic foci, but its role requires further evaluation. As with all functional imaging methods, coregistration with high-quality MRI is essential for interpreting data. 1H MRS can be used also to estimate cerebral concentrations of several neurotransmitters: glutamate, glutamine, and gamma-aminobutyric acid (GABA). This may prove useful for characterizing the neurometabolic profiles of patients with different epilepsy syndromes and for evaluating the effects of medical and surgical treatments. 31P MRS can detect adenosine triphosphate, phosphodiesters, phosphomonoesters, phosphocreatine, and inorganic phosphate, and estimate intracerebral pH. Abnormalities that have been associated with epileptogenic brain areas include increased inorganic phosphate, reduced phosphomonoesters, and increased pH. Only small numbers of patients have been studied, however, so that conclusions are not definitive, and the clinical role of this technique is not yet established.
磁共振波谱（MRS）是非侵入性的，并且可以很容易地与磁共振成像（MRI）相结合。人们的注意力集中在质子（1H）和磷（31P）磁共振波谱上，并且已经通过使用单一体素或同时使用多个体素（化学位移成像、磁共振波谱成像）进行了研究。后者更困难且容易出现伪影，但可能会产生明显更多的信息。1H磁共振波谱主要得出了关于N-乙酰天门冬氨酸（NAA）、胆碱、肌酸和磷酸肌酸浓度的数据。NAA主要位于神经元内，NAA与胆碱、肌酸和磷酸肌酸的比值降低是神经元丢失和功能障碍的一个标志。这项技术作为一种用于定位致痫灶的非侵入性工具可能是有用的，但其作用需要进一步评估。与所有功能成像方法一样，与高质量MRI进行图像配准对于解释数据至关重要。1H磁共振波谱还可用于估计几种神经递质在脑内的浓度：谷氨酸、谷氨酰胺和γ-氨基丁酸（GABA）。这可能对于表征不同癫痫综合征患者的神经代谢特征以及评估药物和手术治疗的效果是有用的。31P磁共振波谱可以检测三磷酸腺苷、磷酸二酯、磷酸单酯、磷酸肌酸和无机磷酸盐，并估计脑内pH值。与致痫脑区相关的异常包括无机磷酸盐增加、磷酸单酯减少和pH值升高。然而，仅对少数患者进行了研究，因此结论并不明确，并且这项技术的临床作用尚未确立。
