Division of Neurosurgery, Department of Surgery, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia; Brain and Cognition Recovery Centre, Gleneagles Medini Hospital, Iskandar Puteri, Johor, Malaysia; Department of Psychology, University of Reading Malaysia, Persiaran Graduan Kota Ilmu, Educity, Johor, Malaysia.
Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, Jalan Universiti, 50603, Kuala Lumpur, Wilayah Persekutuan Kuala Lumpur, Malaysia; University of Malaya Research Imaging Centre, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
Acad Radiol. 2018 Sep;25(9):1167-1177. doi: 10.1016/j.acra.2018.01.005. Epub 2018 Feb 12.
Magnetic resonance spectroscopy is a noninvasive imaging technique that allows for reliable assessment of microscopic changes in brain cytoarchitecture, neuronal injuries, and neurochemical changes resultant from traumatic insults. We aimed to evaluate the acute alteration of neurometabolites in complicated and uncomplicated mild traumatic brain injury (mTBI) patients in comparison to control subjects using proton magnetic resonance spectroscopy (1H magnetic resonance spectroscopy).
Forty-eight subjects (23 complicated mTBI [cmTBI] patients, 12 uncomplicated mTBI [umTBI] patients, and 13 controls) underwent magnetic resonance imaging scan with additional single voxel spectroscopy sequence. Magnetic resonance imaging scans for patients were done at an average of 10 hours (standard deviation 4.26) post injury. The single voxel spectroscopy adjacent to side of injury and noninjury regions were analysed to obtain absolute concentrations and ratio relative to creatine of the neurometabolites. One-way analysis of variance was performed to compare neurometabolite concentrations of the three groups, and a correlation study was done between the neurometabolite concentration and Glasgow Coma Scale.
Significant difference was found in ratio of N-acetylaspartate to creatine (NAA/Cr + PCr) (χ(2) = 0.22, P < .05) between the groups. The sum of NAA and N-acetylaspartylglutamate (NAAG) also shows significant differences in both the absolute concentration (NAA + NAAG) and ratio to creatine (NAA + NAAG/Cr + PCr) between groups (χ(2) = 4.03, P < .05and (χ(2) = 0.79, P < .05)). NAA values were lower in cmTBI and umTBI compared to control group. A moderate weak positive correlation were found between Glasgow Coma Scale with NAA/Cr + PCr (ρ = 0.36, P < .05 and NAA + NAAG/Cr + PCr (ρ = 0.45, P < .05)), whereas a moderate correlation was seen with NAA + NAAG (ρ = 0.38, P < .05).
Neurometabolite alterations were already apparent at onset of both complicated and uncomplicated traumatic brain injury. The ratio of NAA and NAAG has potential to serve as a biomarker reflecting injury severity in a quantifiable manner as it discriminates between the complicated and uncomplicated cases of mTBI.
磁共振波谱是一种非侵入性成像技术，可可靠地评估外伤性损伤引起的脑细胞结构、神经元损伤和神经化学变化的微观变化。我们旨在使用质子磁共振波谱（1H 磁共振波谱）比较复杂和简单轻度创伤性脑损伤（mTBI）患者与对照组之间急性神经代谢物的变化。
48 名受试者（23 名复杂 mTBI [cmTBI]患者、12 名简单 mTBI [umTBI]患者和 13 名对照组）接受磁共振成像扫描，并附加单体素波谱序列。患者的磁共振成像扫描是在受伤后平均 10 小时（标准差 4.26）进行的。分析损伤侧和非损伤侧的单体素波谱，以获得神经代谢物的绝对浓度和与肌酸的比值。对三组神经代谢物浓度进行单因素方差分析，对神经代谢物浓度与格拉斯哥昏迷量表进行相关性研究。
组间 N-乙酰天冬氨酸与肌酸的比值（NAA/Cr+PCr）存在显著差异（χ2=0.22，P<0.05）。NAA 和 N-乙酰天冬氨酸谷氨酸（NAAG）的总和在绝对浓度（NAA+NAAG）和与肌酸的比值（NAA+NAAG/Cr+PCr）方面也存在显著差异（χ2=4.03，P<0.05；（χ2=0.79，P<0.05））。与对照组相比，cmTBI 和 umTBI 中的 NAA 值较低。格拉斯哥昏迷量表与 NAA/Cr+PCr（ρ=0.36，P<0.05）和 NAA+NAAG/Cr+PCr（ρ=0.45，P<0.05）呈中度弱正相关，而与 NAA+NAAG 呈中度相关（ρ=0.38，P<0.05）。
在复杂和简单外伤性脑损伤的发病初期就已经出现神经代谢物改变。NAA 和 NAAG 的比值具有作为反映损伤严重程度的生物标志物的潜力，因为它可以区分复杂和简单的 mTBI 病例。
