正常人胼胝体膝部及嘴部年龄与性别差异的DTI研究

Study of age and sex differences of genu and rostrum of corpus callosum by using diffusion tensor imaging of MRI in normal person

目的:研究胼胝体膝部和嘴部的DTI参数ADC值、部分各项异性(FA)值及神经密度在年龄及性别方面的差异,并获取其随年龄增长的变化规律。方法:将247例正常人按照年龄段分为10组,行颅脑DTI,测量胼胝体膝部和嘴部ROI的ADC值、FA值及神经纤维数,并计算神经密度。结果:①男性胼胝体膝部和嘴部的ADC值随年龄增长的差异均具有统计学意义;女性则差异均无统计学意义。②男性及女性胼胝体膝部和嘴部的FA值随年龄增长差异均具有统计学意义,其随年龄增长的变化规律基本上符合升高—相对稳定—下降的趋势。③男性及女性的胼胝体膝部和嘴部神经密度随年龄增长差异均无统计学意义。④在>3～6岁组,女性胼胝体嘴部的ADC值显著高于男性(P<0.01);在40岁以上男性,胼胝体膝部的神经密度显著高于女性(P<0.01);胼胝体膝部的ADC值和FA值、胼胝体嘴部的FA值和神经密度在各个年龄段内的性别差异均无统计学意义。结论:①胼胝体膝部和嘴部的ADC值、FA值随年龄增长的变化规律可以反映胼胝体膝部和嘴部生长发育及老化的整个过程。②本研究所获得的胼胝体膝部和嘴部的ADC值、FA值及神经密度可作为以后进一步研究的参考。

Objective： To research the differences of MRI ADC value,FA value and nerve density of the genu and rostrum of corpus callosum in the aspects of age and sex,and obtain the change laws with age. Method：247 normal persons were classified into ten groups according to their age and their heads were examined with DTI and DTT of MRI. The ADC value,FA value and nerve fiber number of the ROIs of genu and rostrum of corpus callosum were measured, and then the nerve density was calculat-ed. Results： ①There were significant differences in the ADC values of genu and rostrum of corpus callosum of males with age. The ADC values of genu and rostrum of corpus callosum of females had no significant difference in the age distribution. ②All the FA value differences of genu and rostrum of corpus callosum of males and females were statistically significant with age,and their change laws with age mainly fitted the up- relative stable-down trend. ③All the nerve density differences of genu and rostrum of corpus callosum of males and females as age change were not significant. ④The ADC value of rostrum of corpus callosum of females in the 〉3-6 year old group was significantly higher than that of males（ P〈0.01）. The nerve density of genu of corpus eallosum of males was significantly higher than that of females over 40 years old（ P〈0.01）. In every age group, there were no significant sex differences in the ADC and FA value of genu of corpus callosum and the FA value and nerve density of rostrum of corpus callosum. Conelusions：①The change laws with age of the ADC and FA value of genu and rostrum of corpus callosum can reflect the whole growing, developmental and aging process of genu and rostrum of corpus callosum. ②The ADC value,FA value and nerve density of genu and rostrum of corpus callosum achieved from this study can be a refer-ence to further research.