Abstract：
Diffuse cortical diffusion changes on magnetic resonance imaging (MRI) are characteristically ascribed to global cerebral anoxia, typically after cardiac arrest. Far from being pathognomonic, however, this neuroimaging finding is relatively nonspecific, and can manifest in a myriad of disease states including hypoxia, metabolic derangements, infections, seizure, toxic exposures, and neuroinflammation. While these various conditions can all produce a neuroimaging pattern of widespread cortical diffusion restriction, many of these underlying causes do have subtly unique imaging features that are appreciable on MRI and can be of clinical and diagnostic utility. Specific populations of neurons are variably sensitive to certain types of injury, whether due to differences in perfusion, receptor type density, or the unique tropisms of infectious organisms. In this narrative review, we discuss a number of distinct etiologies of diffuse cortical diffusion restriction on MRI, the unique pathophysiologies responsible for tissue injury, and the resulting neuroimaging characteristics that can be of assistance in differentiating them. As widespread cortical injury from any cause often presents with altered mental status or coma, the differential diagnosis can be enhanced with rapid acquisition of MRI when clinical history or detailed physical examination is limited. In such settings, the distinct imaging features discussed in this article are of interest to both the clinician and the radiologist.
摘要：
磁共振成像（MRI）上的弥漫性皮质弥散变化在特征上归因于全局性脑缺氧，通常是在心脏骤停后.远非病态，然而,这个神经影像学发现是相对非特异性的，并且可以表现为无数的疾病状态，包括缺氧，代谢紊乱，感染,癫痫发作,有毒物质暴露,和神经炎症。虽然这些不同的条件都可以产生广泛的皮质扩散限制的神经影像学模式，这些潜在原因中的许多确实具有独特的影像学特征，这些特征在MRI上是可感知的，并且可能具有临床和诊断价值。特定的神经元群体对某些类型的损伤敏感，是否由于灌注的差异，受体类型密度，或传染性生物的独特嗜性。在这篇叙述性评论中，我们讨论了MRI上弥漫性皮质弥散限制的许多不同病因，负责组织损伤的独特病理生理学，以及由此产生的神经影像学特征，可以帮助区分它们。由于任何原因造成的广泛的皮质损伤往往表现为精神状态改变或昏迷，当临床病史或详细体格检查有限时,快速获取MRI可增强鉴别诊断.在这样的设置中，本文讨论的不同影像学特征对临床医师和放射科医师都有意义.
