Cloak C C, Ernst T, Fujii L, Hedemark B, Chang L
Department of Medicine, John A. Burns School of Medicine, Queen's University Tower, Honolulu, HI 96813, USA.
Neurology. 2009 Jun 16;72(24):2068-75. doi: 10.1212/01.wnl.0000346516.49126.20. Epub 2009 Apr 15.
Methamphetamine use is a common problem among women of childbearing age, leading to an increasing number of children with prenatal methamphetamine exposure. Whether microstructural brain changes associated with prenatal methamphetamine exposure can be detected with diffusion tensor imaging (DTI) is unknown.
Twelve-direction DTI was performed in 29 methamphetamine-exposed and 37 unexposed children ages 3-4 years on a 3-T MRI scanner. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were determined in the corpus callosum (genu and splenium) and bilaterally in the frontal and parietal white matter (WM), basal ganglia (caudate, putamen, globus pallidus), and thalamus.
Children with prenatal methamphetamine exposure had lower ADC in the frontal (right: -2.1%, p = 0.04; left: -2.0%, p = 0.09) and parietal WM (right: -3.9%, p = 0.002; left: -3.3%, p = 0.02) compared to unexposed children. The methamphetamine-exposed children also showed a trend for higher FA in the left frontal WM (+4.9%, p = 0.06) compared to the unexposed children.
Since less myelination and higher dendritic or spine density have been reported in animals exposed to methamphetamine, lower diffusion in our children may reflect more compact axons or greater dendritic or spine density associated with prenatal methamphetamine exposure. These findings suggest alterations in white matter maturation in these children exposed to methamphetamine in utero.
使用甲基苯丙胺是育龄女性中的一个常见问题，导致产前接触甲基苯丙胺的儿童数量不断增加。目前尚不清楚是否可以通过扩散张量成像（DTI）检测出与产前接触甲基苯丙胺相关的脑微观结构变化。
在一台3-T磁共振成像扫描仪上，对29名产前接触甲基苯丙胺的3至4岁儿童和37名未接触甲基苯丙胺的儿童进行了12方向DTI检查。在胼胝体（膝部和压部）以及双侧额叶和顶叶白质（WM）、基底神经节（尾状核、壳核、苍白球）和丘脑区域测定了分数各向异性（FA）和表观扩散系数（ADC）。
与未接触甲基苯丙胺的儿童相比，产前接触甲基苯丙胺的儿童在额叶（右侧：-2.1%，p = 0.04；左侧：-2.0%，p = 0.09）和顶叶白质（右侧：-3.9%，p = 0.002；左侧：-3.3%，p = 0.02）的ADC较低。与未接触甲基苯丙胺的儿童相比，产前接触甲基苯丙胺的儿童在左侧额叶白质中的FA也有升高趋势（+4.9%，p = 0.06）。
由于在接触甲基苯丙胺的动物中已报道有髓鞘形成减少以及树突或棘密度增加的情况，我们研究中儿童较低的扩散可能反映了与产前接触甲基苯丙胺相关的轴突更紧密排列或更大的树突或棘密度。这些发现表明，子宫内接触甲基苯丙胺的这些儿童的白质成熟存在改变。
