R2?鄢值评价健康成年人脑铁含量与年龄的相关性研究

R2* values in estimation of age-related iron deposition in brain of healthy adults

摘要:

目的  采用3.0T增强梯度回波T2?鄢加权血管成像（ESWAN）定量测量健康成年人额叶白质区及灰质核团的R2?鄢值，探讨额叶白质区及灰质核团与年龄的相关性。方法  收集20～85岁的157例健康成年人进行MRI常规及磁敏感加权成像（SWI）扫描，按其年龄段分为6组：A组20～29岁，B组30～39岁，C组40～49岁，D组50～59岁，E组60～69岁，F组≥70岁。经后处理在R2?鄢图像上分别测量双侧额叶白质区、红核、黑质网状带、黑质致密带、尾状核头、壳核、苍白球和丘脑的R2?鄢值，分析R2?鄢值与年龄的相关性。结果  健康成年人在黑质网状带、苍白球的R2?鄢值最低，额叶白质区的R2?鄢值最高。其中黑质网状带、壳核、苍白球、丘脑和尾状核头的R2?鄢值在部分年龄段比较，差异有统计学意义（P <0.05），有一定规律性。而红核、黑质致密带、额叶白质区的R2?鄢值在不同年龄段比较，差异无统计学意义（P >0.05）。红核、黑质网状部、壳核、苍白球、尾状核头的R2?鄢值与年龄呈正相关（r =0.188、0.269、0.524、0.347和0.407，P <0.05），丘脑的R2?鄢值与年龄呈负相关（r =
-0.317，P =0.000），而黑质致密部、额叶白质区的R2?鄢值与年龄无关（P >0.05）。结论  SWI能清晰显示脑内核团的结构，准确评估脑内的铁含量和随年龄变化的规律。

Abstract:

 Objective To quantitatively analyze the iron deposition in deep brain gray nuclei and frontal white matter in healthy population and its correlation with age using enhanced gradient echo T2 star-weighted angiography (ESWAN) with 3.0 Tesla scanner. Methods Totally 157 healthy subjects (ranging 20-85 years) were scanned with routine sequences and ESWAN sequences. The subjects were divided into 6 groups according to their age: group A (age 20-29 years), group B (age 30-31 years), group C (age 40-49 years), group D (age 50-59 years), group E (age 60-69 years) and group F (age > 70 years). R2* value was measured in both sides of frontal white matter, red nucleus, substantia nigra pars reticulate, substantia nigra pars compacta, putamen, globus pallidus, head of caudate nucleus and thalamus; and the correlations between the R2* values and age were analyzed. Results The R2* values of globus pallidus and substantia nigra pars reticulate were the lowest. The highest R2* value was seen in the frontal white matter. The differences of R2* values among some age groups had statistical significance in substantia nigra pars reticulate, putamen, globus pallidus, thalamus and head of caudate nucleus (P < 0.05). Obvious correlations between age and R2* value were shown in substantia nigra pars reticulate (r = 0.269), putamen (r = 0.524), globus pallidus (r = 0.347), head of caudate nucleus (r = 0.407), and thalamus (r = -0.317), while a weak correlation was displayed in red nucleus (r = 0.188). Conclusions ESWAN can clearly display the cerebral nuclei, accurately evaluate the brain iron content and age-related iron concentration changes.