Grassi Daphine Centola, Conceição David Macedo da, Leite Claudia da Costa, Andrade Celi Santos
Departamento de Radiologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brasil.
Arq Neuropsiquiatr. 2018 Mar;76(3):189-199. doi: 10.1590/0004-282x20180007.
Traumatic brain injury (TBI) is the number one cause of death and morbidity among young adults. Moreover, survivors are frequently left with functional disabilities during the most productive years of their lives. One main aspect of TBI pathology is diffuse axonal injury, which is increasingly recognized due to its presence in 40% to 50% of all cases that require hospital admission. Diffuse axonal injury is defined as widespread axonal damage and is characterized by complete axotomy and secondary reactions due to overall axonopathy. These changes can be seen in neuroimaging studies as hemorrhagic focal areas and diffuse edema. However, the diffuse axonal injury findings are frequently under-recognized in conventional neuroimaging studies. In such scenarios, diffuse tensor imaging (DTI) plays an important role because it provides further information on white matter integrity that is not obtained with standard magnetic resonance imaging sequences. Extensive reviews concerning the physics of DTI and its use in the context of TBI patients have been published, but these issues are still hazy for many allied-health professionals. Herein, we aim to review the current contribution of diverse state-of-the-art DTI analytical methods to the understanding of diffuse axonal injury pathophysiology and prognosis, to serve as a quick reference for those interested in planning new studies and who are involved in the care of TBI victims. For this purpose, a comprehensive search in Pubmed was performed using the following keywords: "traumatic brain injury", "diffuse axonal injury", and "diffusion tensor imaging".
创伤性脑损伤（TBI）是青壮年人群死亡和发病的首要原因。此外，幸存者在其生命中最具生产力的岁月里常常会留下功能残疾。TBI病理学的一个主要方面是弥漫性轴索损伤，由于其在所有需要住院治疗的病例中占40%至50%，因此越来越受到认可。弥漫性轴索损伤被定义为广泛的轴索损伤，其特征是完全轴突切断以及由于整体轴突病导致的继发性反应。这些变化在神经影像学研究中可表现为出血性局灶区域和弥漫性水肿。然而，在传统神经影像学研究中，弥漫性轴索损伤的表现常常未得到充分认识。在这种情况下，弥散张量成像（DTI）发挥着重要作用，因为它能提供关于白质完整性的进一步信息，而这是标准磁共振成像序列无法获得的。关于DTI的物理学及其在TBI患者中的应用已有大量综述发表，但对于许多相关健康专业人员来说，这些问题仍然模糊不清。在此，我们旨在综述当前各种先进的DTI分析方法对理解弥漫性轴索损伤病理生理学和预后的贡献，为那些有兴趣规划新研究以及参与TBI受害者护理的人员提供快速参考。为此，我们使用以下关键词在Pubmed上进行了全面搜索：“创伤性脑损伤”、“弥漫性轴索损伤”和“弥散张量成像”。
