氢质子磁共振波谱成像联合磁敏感成像评价弥漫性轴索损伤

Magnetic resonance spectroscopy and susceptibility weighted imaging in evaluation of patients with diffuse axonal injury

目的探讨评价氢质子磁共振波谱（^1H—MRS）和磁敏感成像技术（susceptibility weighted imaging，SWI）在弥漫性轴索损伤（diffuse axonal injury，DAI）的早期诊断治疗中的价值。方法选择2009年9月至2010年8月收治DAI患者24例，分别在伤后1周、1个月行^1H—MRS和SWI检查，再随机选择20例健康成年人作为对照组。比较各组胼胝体压部和基底节N一乙酰天冬氨酸（N—acetylaspartate，NAA）／肌酸和磷酸肌酸（creatine compound，Cr）、胆碱复合物（choline—containing compounds，Cho）／Cr、肌醇（mlNs）／Cr以及谷氨酸和谷氨酰胺（Glx）／Cr等指标的差异。观察T：序列对DAI组病例的检出率；SWI序列观察微出血像素数目及微出血灶检出数。结果与对照组相比，DAI伤后1周、1个月组胼胝体压部NAA／Cr、Cho／Cr、mlNs／Cr、GLx／Cr、基底节区NAA／Cr、Cho／Cr的差异有统计学意义。T2及SWI对轴索病灶的检测率明显提高。24例DAI患者均有微出血。SWI序列及T2序列在微出血像素数及微出血灶数比较差异有统计学意义。结论磁共振波谱技术可反映弥漫性轴索损伤不同时间段局部组织代谢变化，SWI则可检测到微小出血灶，两者结合可更早明确弥漫性轴素损伤的诊断。

Objective To assess the value of H - Magnetic resonance spectroscopy（ ~H - MRS） and susceptibility weighted imaging （ SWI ） in early episodes of diffuse axonal injury （ DAI ）. Methods Twenty - four patients with DAI treated between September 2009 and August 2010 were subjected to H - MRS and SWI examination in the splenium of corpus callosum and basal ganglia at 1 week and 1 month after injury. The neurometabolic alterations were evaluated and compared with those of 20 healthy subjects （ normal controls）. In DAI group the detection rate by T2 sequence and the numbers of micro hemorrhagic pixels and focal detected by SWI sequence were noted. Results There was a significant decrease in NAA/Cr and increase in Cho/Cr, mlNs/Cr, GLx/Cr in the splenium of corpus callosum in patients with DAI as compared with control group（ P 〈 0.05 ） , and there was a significant decrease in NAA/Cr and in- crease in Cho/Cr in basal ganglia. It was easier to find the axonal lesions with T2 and SWI sequence. Microhemorrhage was detected in all 24 patients. The difference between SWI sequence and T2 sequence in numbers of microhemorrhagic pixels and focal had statistical significance. Conclusion ^1H - MRS examination in the splenium of corpus callosum and basal ganglia can detect metabolic changes in different times after injury. SWI can find microhemorrhagic focal. The combination of these two technologies is beneficial for earlier diagnosis of DAI.