目的　通过我国青年人群正中神经的断层解剖测量，为正中神经形态学研究和腕管综合征（CTS）的诊治提供参考。  方法　共采集28例志愿者56侧腕部MRI数据，测量计算正中神经横截面积（CSA）、扁平率（MNFR）和膨胀率（MNSR）并进行性别之间、双侧肢体间比较，再将上述指标分别与年龄、身高、体重进行相关分析。  结果　正中神经CSA、MNFR和MNSR在双侧肢体之间无统计学差异；CSA和MNSR在性别之间无统计学差异；而女性MNFR显著大于男性，差异具有统计学意义，而MNFR与身高存在着统计学负相关性。  结论　基于MRI（1.5T）正中神经的解剖测量具有可靠和精度高的特点；国人正中神经CSA存在着性别间差异，和西方人CSA相比差异较大，CSA和身高存在负相关性；CTS的MRI诊断标准应与国人解剖参数相结合。

Objective    To investigate the value of quantitative anatomy of me-dian nerve in carpal tunnel among adolescent in the diagnosis and treatment for carpal tunnel syndrome.     Methods     A total of 56 wrists from 28 adolescents were collected via magnetic resonance imaging. Cross section area (CSA), swelling rate ofmedian nerve (MNSR) and flatteningrate of median nerve (MNFR) were measured according to magnetic resonance images from multiple sections of carpal tunnel, and were com-pared between genders as well as bilateral upper limbs. Regarding CSA, MNSR and MNFR, perimeters including age, body height and body weight were considered as potential correlative factors for further correlation analysis.   Result    With regard to CSA, MNFR and MNSR, no statistical difference was found between bilateral upper limbs. No statistical difference was found between genders concerning  CSA and MNSR as well. MNFR in female was found to be statistically higher than that in male while a significant negative correlation was observed between MNFR and body height.    Conclusion    Magnetic resonance imaging(1.5T) used in quantitative anatomy of median nerve in carpal tunnel showed advantages of reliability and precision. There was significant difference between genders in Chinese adolescents regarding MNFR. The MNFR, having negative correlation with body height, appears to be much lower in Chinese individuals than that in westerners. For the Chinese individuals, the diagnostic standard for carpal tunnel syndrome based on MRI should be established referring to Chinese anatomical feature.