正常婴幼儿脑外间隙的随龄性变化规律

摘要

目的 应用磁共振成像测量正常婴幼儿不同部位脑外间隙宽度,观察其随年龄变化的规律,为脑积水的定量诊断奠定基础.方法 采集213例正常婴幼儿头颅M RI平扫数据,测量前纵裂及双侧额前间隙的宽度.采用(均数±标准差)表达各年龄组的脑外间隙宽度;秩和检验比较性别、颅内侧别之间的脑外间隙宽度差异;散点图拟合回归曲线观察脑外间隙宽度随年龄的变化趋势.结果 婴幼儿脑外间隙宽度随年龄增长呈先增宽后变窄的趋势,且具有2个转折点,4月龄脑外间隙最宽,1岁以后趋于平缓.脑外间隙宽度在性别之间无统计学差异(P＞0.05),而颅内侧别之间差异具有统计学意义(P＜0.05).结论 脑外间隙宽度是一个动态变化的生理过程,尤其是＜10月龄的婴儿;病理性外部性脑积水的准确诊断不仅要参照不同月龄的脑外间隙宽度参考指标,更要密切结合临床病史.%Objective To measure the extracerebral space width of normal infants with magnetic resonance imaging(MRI)and observe the variation tendency with age for quantitative diagnosis of hydrocephalus.Methods We measured the distance of interhemispheric fissure and bilateral frontal subarachnoid space on MRI images of 213 normal infants.The width of extracerebral space was expressed as mean ± standard deviation.The gender and bilateral differences were compared by rank sum test,and the variation trend of extracerebral space with age was observed by the scatterplots fitting regression curve.Results The width of infant extracerebral space had two milestones,4-month-old extracerebral space was the widest,and the amplitude of variation tended to be mild after 1 year of age.There was no significant difference between the genders in gap of extracerebral space(P＞ 0.05). However,bilateral frontal subarachnoid space differed significantly between genders(P＜0.05).Conclusion The width of extracerebral space,a dynamic process with age in infants,is most pronounced under 10 months old.The accurate diagnosis of pathological external hydrocephalus should be based on the reference value of the extracerebral space at different months,and it is very important to combine it closely with clinical history.