3.0T磁共振波谱成像在婴幼儿脑白质发育评价中的应用研究

Application of 3.0T magnetic resonance spectroscopy imaging in the evaluation on the development of normal brain white matter in infants and young children

目的测定正常婴幼儿脑白质中氢质子波谱代谢物峰下面积,观察其波峰特点并探讨各代谢物峰下面积比值与年龄的关系。方法对180名不同年龄段的正常婴幼儿侧脑室旁白质进行多体素1H-MRS波谱分析,测定代谢物中N-乙酰天门冬氨酸(NAA)、胆碱(Cho)、肌酸(Cr)的峰下面积并计算NAA/Cho、NAA/Cr、Cho/Cr比值。结果随年龄增长,侧脑室旁白质中NAA逐渐增高;Cho逐渐减低,于2岁末趋于稳定;Cr 3个月内明显升高,4个月后趋于稳定。侧脑室旁白质代谢物峰下面积比值在不同年龄组间的差异有统计学意义(P<0.05)。侧脑室旁白质的NAA/Cho、NAA/Cr与年龄呈正相关(r=0.741,r=0.625,P<0.05),Cho/Cr与年龄呈负相关(r=–0.552,P<0.05)。结论不同年龄婴幼儿脑白质各代谢物峰下面积不同。脑白质代谢物峰下面积比值与年龄均有一定相关性,可为小儿正常脑发育、异常脑代谢提供临床诊断依据。

Objective To calculate the radios of peak area of proton magnetic resonance spectroscopy metabolites in brain white matter of normal infants and young children, to observe the features of metabolite spectra, and to explore the relations between their ratio with age. Methods The peak areas ofmetabolites, including N-acetyl aspartatg （NAA）, choline （Cho）, creatine （Cr）, and their ratio of NAA/Cho, NAA/Cr, Cho/Cr, in paraventricular white matter of 180 normal infants and young children with different ages as evaluated by multi-voxel proton magnetic resonance spectroscopy. Results In paraventricular white matter, spectrum of NAA increased, and that of Cho decreased gradually, while both of them were stabilized at 2 years old. Cr was increased obviously within 3 months, and stabilized after 4 months. Significant differences were found in ratio of different metabolites in paraventricular white matter in different ages （P〈0.05）. The ratios of NAA/Cho and NAA/Cr in paraventricular white mater were positively correlated with age （r=0.741, r=0.625）, while that of Cho/Cr was negatively correlated with age （r=-0.SS2, P〈0.05）. Conclusion The ratios of different metabolites are different in brain white matter in infants of different ages. Metabolites concentrations in brain white matter are correlated to some extent with age, which may provide a diagnostic criterion for evaluation of normal brain development and abnormal brain metabolism.