Department of Neurological Surgery, The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida, United States of America.
Department of Radiation Oncology, University of Miami Miller School of Medicine, Miami, Florida, United States of America.
PLoS One. 2023 Aug 7;18(8):e0289786. doi: 10.1371/journal.pone.0289786. eCollection 2023.
Traumatic brain injury (TBI) is a worldwide problem that results in death or disability for millions of people every year. Progressive neurological complications and long-term impairment can significantly disrupt quality of life. We demonstrated the feasibility of multiple magnetic resonance imaging (MRI) modalities to investigate and predict aberrant changes and progressive atrophy of gray and white matter tissue at several acute and chronic time points after moderate and severe parasagittal fluid percussion TBI. T2-weighted imaging, diffusion tensor imaging (DTI), and perfusion weighted imaging (PWI) were performed. Adult Sprague-Dawley rats were imaged sequentially on days 3, 14, and 1, 4, 6, 8, and 12 months following surgery. TBI caused dynamic white and gray matter alterations with significant differences in DTI values and injury-induced alterations in cerebral blood flow (CBF) as measured by PWI. Regional abnormalities after TBI were observed in T2-weighted images that showed hyperintense cortical lesions and significant cerebral atrophy in these hyperintense areas 1 year after TBI. Temporal DTI values indicated significant injury-induced changes in anisotropy in major white matter tracts, the corpus callosum and external capsule, and in gray matter, the hippocampus and cortex, at both early and chronic time points. These alterations were primarily injury-severity dependent with severe TBI exhibiting a greater degree of change relative to uninjured controls. PWI evaluating CBF revealed sustained global reductions in the cortex and in the hippocampus at most time points in an injury-independent manner. We next sought to investigate prognostic correlations across MRI metrics, timepoints, and cerebral pathology, and found that diffusion abnormalities and reductions in CBF significantly correlated with specific vulnerable structures at multiple time points, as well as with the degree of cerebral atrophy observed 1 year after TBI. This study further supports using DTI and PWI as a means of prognostic imaging for progressive structural changes after TBI and emphasizes the progressive nature of TBI damage.
创伤性脑损伤（TBI）是一个全球性问题，每年导致数百万人死亡或残疾。进行性神经并发症和长期损伤会显著破坏生活质量。我们证明了多种磁共振成像（MRI）方式的可行性，这些方式可用于在中度和重度矢状窦旁液压冲击 TBI 后的几个急性和慢性时间点研究和预测灰、白质组织的异常变化和进行性萎缩。进行了 T2 加权成像、弥散张量成像（DTI）和灌注加权成像（PWI）。对成年 Sprague-Dawley 大鼠进行了手术后继发性的 3、14、1、4、6、8 和 12 个月的连续成像。TBI 导致了动态的白质和灰质改变，DTI 值有显著差异，PWI 测量的脑血流（CBF）损伤诱导改变。TBI 后在 T2 加权图像中观察到区域异常，这些异常表现为皮质高信号病变，并且在 TBI 后 1 年这些高信号区域出现明显的脑萎缩。DTI 时间表明，主要的白质束、胼胝体和外囊以及灰质、海马和皮质的各向异性在早期和慢性时间点都有明显的损伤诱导变化。这些改变主要与损伤严重程度有关，重度 TBI 与未受伤对照相比，变化程度更大。评估 CBF 的 PWI 以损伤无关的方式显示皮质和海马在大多数时间点的全局 CBF 持续减少。我们接下来试图研究 MRI 指标、时间点和脑病理学之间的预后相关性，发现弥散异常和 CBF 减少与多个时间点的特定脆弱结构以及 TBI 后 1 年观察到的脑萎缩程度显著相关。这项研究进一步支持使用 DTI 和 PWI 作为 TBI 后进行性结构变化的预后成像手段，并强调了 TBI 损伤的进行性性质。
