Takanashi Jun-Ichi, Uetani Hiroyuki
Department of Pediatrics, Tokyo Women's Medical University Yachiyo Medical Center, Yachiyo, Japan.
Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
Front Neurosci. 2023 Aug 10;17:1235364. doi: 10.3389/fnins.2023.1235364. eCollection 2023.
Acute encephalopathy associated with infectious diseases occurs frequently in Japanese children (400-700 children/year) and is the most common in infants aged 0-3 years. Acute encephalopathy is classified into several clinicoradiological syndromes; acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) is the most common subtype, followed by clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) and acute necrotizing encephalopathy (ANE). Neuroimaging, especially magnetic resonance imaging (MRI), is useful for the diagnosis, assessment of treatment efficacy, and evaluation of the pathophysiology of encephalopathy syndromes. MRI findings essential for diagnosis include delayed subcortical reduced diffusion (bright tree appearance) for AESD, reversible splenial lesions with homogeneously reduced diffusion for MERS, and symmetric hemorrhagic thalamic lesions for ANE. We reviewed several MRI techniques that have been applied in recent years, including diffusion-weighted imaging for the characterization of cerebral edema, arterial spin labeling for evaluating cerebral perfusion, and magnetic resonance spectroscopy for evaluating metabolic abnormality.
急性感染性脑病在日本儿童中频繁发生（每年400 - 700例儿童），在0 - 3岁婴幼儿中最为常见。急性脑病可分为几种临床放射学综合征；伴有双相惊厥和晚期弥散受限的急性脑病（AESD）是最常见的亚型，其次是伴有可逆性胼胝体病变的临床轻度脑炎/脑病（MERS）和急性坏死性脑病（ANE）。神经影像学检查，尤其是磁共振成像（MRI），对于诊断、评估治疗效果以及评价脑病综合征的病理生理学很有用。诊断所必需的MRI表现包括AESD的皮质下延迟弥散受限（亮树征）、MERS的具有均匀弥散受限的可逆性胼胝体病变以及ANE的对称性丘脑出血性病变。我们回顾了近年来应用的几种MRI技术，包括用于表征脑水肿的弥散加权成像、用于评估脑灌注的动脉自旋标记以及用于评估代谢异常的磁共振波谱分析。
