Cognitive impairments are common following a traumatic brain injury (TBI) and frequently result from white matter (WM) damage. This damage can be quantified using diffusion tensor imaging (DTI), which measures the directionality (fractional anisotropy: FA) and amount (mean diffusivity/apparent diffusion coefficient: MD/ADC) of water diffusion in WM, with high FA and low MD/ADC thought to indicate greater WM integrity. However, the relationship between DTI and cognitive outcomes is currently unclear. The data from 20 studies that examined the relationship between WM integrity (measured using DTI) and cognition (categorised into seven domains) following mild-severe adult TBI were meta-analysed. Overall, high FA and low MD/ADC in most brain regions was associated with better cognitive performance, with memory and attention most strongly related to DTI findings. Specifically, memory and/or attention were very strongly related to DTI findings in the corpus callosum, fornix, internal capsule, arcuate and uncinate fasciculi. However, most findings were based on single studies and therefore await replication. Larger-scale, longitudinal studies are now needed to determine the predictive utility of DTI.

认知损伤是脑外伤（TBI）之后的常见现象，通常是由白质（WM）损伤引起的。可以使用扩散张量成像（DTI）来量化这种破坏，扩散张量成像（DTI）可以测量WM中水扩散的方向性（分数各向异性：FA）和水扩散的量（平均扩散率/表观扩散系数：MD / ADC），其中高FA和低MD / ADC被认为表明WM完整性更高。但是，DTI和认知结果之间的关系目前尚不清楚。对来自20项研究的数据进行荟萃分析，这些研究检查了WM完整性（使用DTI测量）和认知（分为七个领域）与认知（分为七个领域）之间的关系。总体而言，大多数大脑区域的高FA和低MD / ADC与较好的认知表现有关，记忆力和注意力与DTI发现最密切相关。具体而言，记忆和/或注意力与call体，穹ni，内囊，弓形和钩状浅束中的DTI发现密切相关。但是，大多数发现是基于单项研究，因此有待复制。现在需要进行大规模的纵向研究来确定DTI的预测效用。