Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
Neuroimage. 2011 Feb 1;54(3):1774-85. doi: 10.1016/j.neuroimage.2010.10.037. Epub 2010 Oct 18.
Preterm birth with very low birth weight (VLBW, ≤1500 g) is connected to reduced white matter (WM) integrity in childhood and adolescence. These changes in WM are correlated to motor, sensory and neuropsychological impairments. CNS myelination continues into the early twenties, but the consequences of this for WM integrity in VLBWs have not been explored. DTI and tract based spatial statistics (TBSS) was carried out to test for voxelwise differences in fractional anisotropy (FA), eigenvalues and mean diffusivity (MD) between a preterm VLBW group (n=49) and a control group born at term (n=59) at 18-22 years of age. TBSS was also used to explore the relationship between perinatal clinical data and general cognitive ability (total IQ), respectively, and the DTI metrics (FA and MD), with gender and age as a confounder. In the VLBW group several major WM tracts particularly in the posterior region had significantly reduced FA caused by an increase in the two lowest eigenvalues. MD was significantly increased in the VLBWs in 50% of the same regions as the FA changes, but encompassing also more peripheral WM. In the VLBW group, FA was found to correlate positively with birth weight and negatively with number of days in intensive care and on mechanical ventilator, particularly in the corpus callosum. FA was found to correlate positively with total IQ in the young preterm adults. In the controls there was no correlation between FA and total IQ. Our results indicate that the neurologic sequelae of preterm birth with VLBW are a lifelong condition inducing structural and functional impairments also in adulthood in VLBW survivors. The greatest risk of having reduced WM integrity in adulthood was found in the most immature VLBW neonates requiring mechanical ventilation and long-term intensive care.
极早早产儿（VLBW，体重≤1500 克）出生与儿童和青少年时期的白质（WM）完整性降低有关。WM 的这些变化与运动、感觉和神经心理障碍有关。中枢神经系统的髓鞘形成持续到 20 岁出头，但尚未探讨这对 VLBW 患者 WM 完整性的影响。DTI 和基于束的空间统计（TBSS）用于测试 18-22 岁时极早早产儿 VLBW 组（n=49）和足月出生对照组（n=59）之间各向异性分数（FA）、特征值和平均弥散度（MD）的体素差异。TBSS 还用于分别探索围产期临床数据与一般认知能力（总智商）之间的关系，以及 DTI 指标（FA 和 MD），以性别和年龄为混杂因素。在 VLBW 组中，几个主要的 WM 束，特别是在后区，由于两个最低特征值的增加，FA 明显降低。MD 在 VLBW 中明显增加，与 FA 变化相同的 50%区域，但也包括更多的外周 WM。在 VLBW 组中，FA 与出生体重呈正相关，与重症监护和机械通气天数呈负相关，尤其是胼胝体。FA 与年轻早产儿的总智商呈正相关。在对照组中，FA 与总智商之间没有相关性。我们的研究结果表明，VLBW 极早早产的神经后遗症是一种终身疾病，即使在 VLBW 幸存者的成年期也会引起结构和功能障碍。在成年期 WM 完整性降低的最大风险出现在最不成熟的 VLBW 新生儿中，他们需要机械通气和长期重症监护。
