Thompson Deanne K, Omizzolo Cristina, Adamson Christopher, Lee Katherine J, Stargatt Robyn, Egan Gary F, Doyle Lex W, Inder Terrie E, Anderson Peter J
Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, Australia; Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Australia.
Hum Brain Mapp. 2014 Aug;35(8):4129-39. doi: 10.1002/hbm.22464. Epub 2014 Feb 12.
The effects of prematurity on hippocampal development through early childhood are largely unknown. The aims of this study were to (1) compare the shape of the very preterm (VPT) hippocampus to that of full-term (FT) children at 7 years of age, and determine if hippocampal shape is associated with memory and learning impairment in VPT children, (2) compare change in shape and volume of the hippocampi from term-equivalent to 7 years of age between VPT and FT children, and determine if development of the hippocampi over time predicts memory and learning impairment in VPT children. T1 and T2 magnetic resonance images were acquired at both term equivalent and 7 years of age in 125 VPT and 25 FT children. Hippocampi were manually segmented and shape was characterized by boundary point distribution models at both time-points. Memory and learning outcomes were measured at 7 years of age. The VPT group demonstrated less hippocampal infolding than the FT group at 7 years. Hippocampal growth between infancy and 7 years was less in the VPT compared with the FT group, but the change in shape was similar between groups. There was little evidence that the measures of hippocampal development were related to memory and learning impairments in the VPT group. This study suggests that the developmental trajectory of the human hippocampus is altered in VPT children, but this does not predict memory and learning impairment. Further research is required to elucidate the mechanisms for memory and learning difficulties in VPT children.
早产对幼儿期海马体发育的影响在很大程度上尚不清楚。本研究的目的是：（1）比较极早产儿（VPT）与足月儿（FT）7岁时海马体的形状，并确定海马体形状是否与VPT儿童的记忆和学习障碍相关；（2）比较VPT儿童和FT儿童从足月等效年龄到7岁时海马体形状和体积的变化，并确定海马体随时间的发育是否能预测VPT儿童的记忆和学习障碍。对125名VPT儿童和25名FT儿童在足月等效年龄和7岁时均采集了T1和T2磁共振图像。在两个时间点对海马体进行手动分割，并用边界点分布模型对形状进行表征。在7岁时测量记忆和学习结果。VPT组在7岁时海马体的褶皱比FT组少。与FT组相比，VPT组婴儿期至7岁期间海马体的生长较少，但两组之间的形状变化相似。几乎没有证据表明海马体发育指标与VPT组的记忆和学习障碍有关。本研究表明，VPT儿童人海马体的发育轨迹发生了改变，但这并不能预测记忆和学习障碍。需要进一步研究以阐明VPT儿童记忆和学习困难的机制。
