Schubert Florian, Seifert Frank, Elster Clemens, Link Alfred, Walzel Monika, Mientus Susanne, Haas Judith, Rinneberg Herbert
Department of Medical Physics and Metrological Information Technology, Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, D-10587, Berlin, Germany.
MAGMA. 2002 Jun;14(3):213-22. doi: 10.1007/BF02668215.
To assess the applicability of magnetic resonance spectroscopy (MRS) for long-term follow-up of neurological diseases a longitudinal 1H-MRS study at 3 T was carried out on ten patients having relapsing-remitting multiple sclerosis (MS) who, after baseline examination, received interferon-beta (IFN) 1b. At 8-20 examinations within up to 34 months absolute concentrations of N-acetylaspartate (NAA), total creatine (tG), and choline-containing compounds (tCho) were determined in a large non-enhancing lesion and contralateral normal appearing white matter (NAWM). MR spectra were analyzed using a novel time domain-frequency domain method including non-parametric background characterization. For comparison at baseline, ten healthy controls were examined. The concentrations of tCho and tCr were found to be higher in MS brain than in control brain. Besides a non-significantly lower NAA concentration in lesions there were no concentration differences between lesions and NAWM. Over the follow-up period the measured metabolite concentrations exhibited a high variability. Most concentrations remained within this scatter, and statistical tests revealed significant fluctuations in the levels of metabolites in one case only. This stability of the metabolite concentrations over time might result from IFN therapy as for the spontaneous course of relapsing-remitting MS decreasing metabolite (NAA/tCr) ratios have been reported. The results further suggest that future treatment trials intending to use metabolite concentrations as a secondary outcome indicator use even longer observation periods and, besides group analysis of large cohorts, investigate the time behavior of selected single cases. The biochemical abnormalities found in NAWM emphasize the importance of analyzing both lesion and NAWM.
为评估磁共振波谱（MRS）在神经系统疾病长期随访中的适用性，对10例复发缓解型多发性硬化（MS）患者进行了一项3T的纵向1H-MRS研究。这些患者在基线检查后接受了干扰素-β（IFN）1b治疗。在长达34个月的8 - 20次检查中，测定了一个大的非强化病灶及对侧正常白质（NAWM）中N-乙酰天门冬氨酸（NAA）、总肌酸（tG）和含胆碱化合物（tCho）的绝对浓度。使用一种包括非参数背景特征的新型时域-频域方法分析磁共振波谱。作为基线比较，检查了10名健康对照者。发现MS患者脑内tCho和tCr的浓度高于对照者脑内。除了病灶中NAA浓度无显著降低外，病灶与NAWM之间没有浓度差异。在随访期间，所测代谢物浓度表现出高度变异性。大多数浓度保持在这种散点范围内，统计检验仅在1例中显示代谢物水平有显著波动。随着时间推移代谢物浓度的这种稳定性可能是由于IFN治疗导致的，因为据报道复发缓解型MS的自然病程中代谢物（NAA/tCr）比值会降低。结果进一步表明，未来旨在将代谢物浓度用作次要结局指标的治疗试验应使用更长的观察期，并且除了对大样本队列进行组分析外，还要研究选定单病例的时间行为。在NAWM中发现的生化异常强调了分析病灶和NAWM两者的重要性。
