自身免疫性脑炎（AE）是一类影响儿童和成人的免疫介导的中枢神经系统（CNS）疾病。其特征是亚急性发作的精神状态改变、神经认知问题、难治性癫痫/耐药性癫痫、运动障碍和/或自主神经功能障碍。 AE 由针对中枢神经系统中特定表面成分或胞浆内抗原的自身抗体介导，导致功能或结构改变。已描述了多种诱发自身免疫的触发因素，主要是副感染性和副肿瘤性。 AE 的影像学特征常常相互重叠，并与脑炎/脑病的其他常见原因（感染和毒性代谢病因）重叠。边缘脑炎是大多数这些实体共有的最常见的影像学表现。皮质、基底神经节、间脑和脑干也可能受累。小脑受累很少见，通常是副肿瘤变性的一部分。由于对 AE 了解的加深，其发生率和检出率有所增加。因此，在适当的情况下，在报告临床 MRI 时保持高度怀疑至关重要，以确保及时治疗和更好的患者治疗结果。在这篇综述中，我们讨论了 AE 的病理生理学和临床实践中遇到的常见病因。版权所有 © 2024 韩国放射学会。

Autoimmune encephalitis (AE) is a category of immune-mediated disorders of the central nervous system (CNS) affecting children and adults. It is characterized by the subacute onset of altered mentation, neurocognitive issues, refractory seizures/drug-resistant epilepsy, movement disorders, and/or autonomic dysfunction. AE is mediated by autoantibodies targeting specific surface components or intracytoplasmic antigens in the CNS, leading to functional or structural alterations. Multiple triggers that induce autoimmunity have been described, which are mainly parainfectious and paraneoplastic. The imaging features of AE often overlap with each other and with other common causes of encephalitis/encephalopathy (infections and toxic-metabolic etiologies). Limbic encephalitis is the most common imaging finding shared by most of these entities. Cortical, basal ganglia, diencephalon, and brainstem involvement may also be present. Cerebellar involvement is rare and is often a part of paraneoplastic degeneration. Owing to an improved understanding of AE, their incidence and detection have increased. Hence, in an appropriate setting, a high degree of suspicion is crucial when reporting clinical MRIs to ensure prompt treatment and better patient outcomes. In this review, we discuss the pathophysiology of AE and common etiologies encountered in clinical practice.Copyright © 2024 The Korean Society of Radiology.