【摘要】 目的 探讨正常中晚孕胎儿脑额叶信号值随胎龄增长变化的一般规律。方法 将125例正常中晚孕胎儿按胎龄大小分成5组(单位:周),即17～21、22～26、27～31、32～36、37～40。分别测量各胎龄组额叶下部、中部及上部的信号值;计数并进行统计学分析。结果 17～21、22～26、27～31、32～36、37～40胎龄组额叶信号值大小分别为387.38±166.75、354.46±174.78、342.24±141.23、338.90±110.94、310.23±118.62;额叶下、中、上部的信号值大小分别为341.77±149.22、351.00±145.16、342.85±140.61,额叶左右侧信号值分别为350.34±147.68、340.73±144.29;经方差分析显示,各胎龄段组间,额叶上、中、下部及额叶左右部间P> 0.05,差异无统计学意义,但额叶信号随胎龄增长呈逐渐减低,额叶中部大于额叶上、下部,额叶左侧略大于右侧。结论 正常中晚孕胎儿脑额叶信号值随胎龄增长逐渐减低,额叶中部大于额叶上、下部,左侧略大于右侧。更多还原

【Abstract】 Objective To explore the change of signal value in the fetal frontal lobe with gestational age in normal second-third trimester fetuses.Methods MRI findings of 125 normal second-third trimester fetuses were divided into 5 groups according to gestational age(unit:week) including 17-21,22-26,27-31,32-36,37-40,respectively.The signal values were measured in inferior frontal,middle and upper,respectively.Results The signal value of fetal frontal lobe in 5 groups were 387.38±166.75,354.46±174.78,342.24±141.23,338.90±110.94,310.23±118.62,respectively.The signal value was 341.77±149.22,351.00±145.16,342.85±140.61 in inferior frontal,middle and upper,respectively.The signal value of frontal lobe was 350.34±147.68 in the left and 340.73±144.29 in the right.There were no significant statistical differences on fetal frontal lobe signal value in each group(P>0.05).But the signal value in the frontal lobe had a gradually decreasing trend with fetal age,along with the signal value in the central frontal was higher than the other two parts of the frontal lobe and the left is slightly higher than the right.Conclusion The signal values in frontal lobe of normal second-third trimester fetuses were gradually decreased as gestational age increasing,with the signal values in central frontal lobe was higher than that of in margin of frontal lobe,and the left side was slightly higher than the right.更多还原