Rule R R, Suhy J, Schuff N, Gelinas D F, Miller R G, Weiner M W
Department of Radiology, University of California, San Francisco, CA, USA.
Amyotroph Lateral Scler Other Motor Neuron Disord. 2004 Sep;5(3):141-9. doi: 10.1080/14660820410017109.
After replication of previous findings we aimed to: 1) determine if previously reported (1)H MRSI differences between ALS patients and control subjects are limited to the motor cortex; and 2) determine the longitudinal metabolic changes corresponding to varying levels of diagnostic certainty.
Twenty-one patients with possible/suspected ALS, 24 patients with probable/definite ALS and 17 control subjects underwent multislice (1)H MRSI co-registered with tissue-segmented MRI to obtain concentrations of the brain metabolites N-acetylaspartate (NAA), creatine, and choline in the left and right motor cortex and in gray matter and white matter of non-motor regions in the brain.
In the more affected hemisphere, reductions in the ratios, NAA/Cho and NAA/Cre+Cho were observed both within (12.6% and 9.5% respectively) and outside (9.2% and 7.3% respectively) the motor cortex in probable/definite ALS. However, these reductions were significantly greater within the motor cortex (P<0.05 for NAA/Cho and P<0.005 for NAA/Cre+Cho). Longitudinal changes in NAA were observed at three months within the motor cortex of both possible/suspected ALS patients (P<0.005) and at nine months outside the motor cortex of probable/definite patients (P<0.005). However, there was no clear pattern of progressive change over time.
NAA ratios are reduced in the motor cortex and outside the motor cortex in ALS, suggesting widespread neuronal injury. Longitudinal changes of NAA are not reliable, suggesting that NAA may not be a useful surrogate marker for treatment trials.
在重复先前研究结果后，我们旨在：1）确定先前报道的肌萎缩侧索硬化症（ALS）患者与对照受试者之间的氢质子磁共振波谱成像（¹H MRSI）差异是否仅限于运动皮层；2）确定与不同诊断确定性水平相对应的纵向代谢变化。
21例可能/疑似ALS患者、24例很可能/确诊ALS患者和17名对照受试者接受了多层¹H MRSI检查，并与组织分割MRI进行配准，以获取左、右运动皮层以及脑非运动区域灰质和白质中脑代谢物N-乙酰天门冬氨酸（NAA）、肌酸和胆碱的浓度。
在受累更严重的半球，在很可能/确诊的ALS患者中，运动皮层内（分别为12.6%和9.5%）和运动皮层外（分别为9.2%和7.3%）的NAA/胆碱（Cho）和NAA/（肌酸+胆碱）（Cre+Cho）比值均降低。然而，这些降低在运动皮层内更为显著（NAA/Cho，P<0.05；NAA/Cre+Cho，P<0.005）。在可能/疑似ALS患者的运动皮层内三个月时观察到NAA的纵向变化（P<0.005），在很可能/确诊患者的运动皮层外九个月时也观察到NAA的纵向变化（P<0.005）。然而，随着时间的推移，没有明显的渐进性变化模式。
ALS患者的运动皮层和运动皮层外NAA比值降低，提示广泛的神经元损伤。NAA的纵向变化不可靠，提示NAA可能不是治疗试验的有用替代标志物。
