Table_1_A Preliminary DTI Tractography Study of Developmental Neuroplasticity 5–15 Years After Early Childhood Traumatic Brain Injury.DOCX

Plasticity is often implicated as a reparative mechanism when addressing structural and functional brain development in young children following traumatic brain injury (TBI); however, conventional imaging methods may not capture the complexities of post-trauma development. The present study examined the cingulum bundles and perforant pathways using diffusion tensor imaging (DTI) in 21 children and adolescents (ages 10–18 years) 5–15 years after sustaining early childhood TBI in comparison with 19 demographically-matched typically-developing children. Verbal memory and executive functioning were also evaluated and analyzed in relation to DTI metrics. Beyond the expected direction of quantitative DTI metrics in the TBI group, we also found qualitative differences in the streamline density of both pathways generated from DTI tractography in over half of those with early TBI. These children exhibited hypertrophic cingulum bundles relative to the comparison group, and the number of tract streamlines negatively correlated with age at injury, particularly in the late-developing anterior regions of the cingulum; however, streamline density did not relate to executive functioning. Although streamline density of the perforant pathway was not related to age at injury, streamline density of the left perforant pathway was significantly and positively related to verbal memory scores in those with TBI, and a moderate effect size was found in the right hemisphere. DTI tractography may provide insight into developmental plasticity in children post-injury. While traditional DTI metrics demonstrate expected relations to cognitive performance in group-based analyses, altered growth is reflected in the white matter structures themselves in some children several years post-injury. Whether this plasticity is adaptive or maladaptive, and whether the alterations are structure-specific, warrants further investigation.

在探讨年幼儿童在遭受脑外伤（TBI）后的结构和功能脑部发育时，塑性常常被视为一种修复机制；然而，传统的成像技术可能无法捕捉到创伤后发展的复杂性。本研究采用扩散张量成像（DTI）技术对21名儿童和青少年（年龄在10至18岁之间）的扣带回束和穿通路径进行了检查，这些儿童在5至15年前曾因早年儿童期TBI而受伤，并与19名在人口统计学上匹配的典型发展儿童进行了比较。同时，还评估并分析了这些儿童的言语记忆和执行功能，并将其与DTI指标相关联。在TBI组中，除了预期到的定量DTI指标的方向外，我们还在超过一半的早期TBI患者中发现，由DTI轨迹图生成的两条路径的流线密度存在质的变化。与对照组成员相比，这些儿童的扣带回束呈现出明显的肥大，且轨迹线的数量与受伤时的年龄呈负相关，尤其是在扣带回的前部晚发展区域；然而，流线密度与执行功能无相关性。尽管穿通路径的流线密度与受伤时的年龄无相关性，但左侧穿通路径的流线密度与TBI患者的言语记忆分数显著正相关，且在右侧半球发现了中等程度的效果大小。DTI轨迹图可能为儿童受伤后的发育塑性提供洞察。虽然传统的DTI指标在基于群体的分析中显示出与认知表现的预期关系，但在一些儿童的白质结构中，受伤数年后反映出的生长变化。这种塑性是适应性还是非适应性，以及这些变化是否具有结构特异性，都需要进一步的调查研究。（Plasticity is often implicated as a reparative mechanism when addressing structural and functional brain development in young children following traumatic brain injury (TBI); however, conventional imaging methods may not capture the complexities of post-trauma development. The present study examined the cingulum bundles and perforant pathways using diffusion tensor imaging (DTI) in 21 children and adolescents (ages 10–18 years) 5–15 years after sustaining early childhood TBI in comparison with 19 demographically-matched typically-developing children. Verbal memory and executive functioning were also evaluated and analyzed in relation to DTI metrics. Beyond the expected direction of quantitative DTI metrics in the TBI group, we also found qualitative differences in the streamline density of both pathways generated from DTI tractography in over half of those with early TBI. These children exhibited hypertrophic cingulum bundles relative to the comparison group, and the number of tract streamlines negatively correlated with age at injury, particularly in the late-developing anterior regions of the cingulum; however, streamline density did not relate to executive functioning. Although streamline density of the perforant pathway was not related to age at injury, streamline density of the left perforant pathway was significantly and positively related to verbal memory scores in those with TBI, and a moderate effect size was found in the right hemisphere. DTI tractography may provide insight into developmental plasticity in children post-injury. While traditional DTI metrics demonstrate expected relations to cognitive performance in group-based analyses, altered growth is reflected in the white matter structures themselves in some children several years post-injury. Whether this plasticity is adaptive or maladaptive, and whether the alterations are structure-specific, warrants further investigation.）