Abstract:
The hippocampus is a complex structure located in the mesial temporal lobe that plays a critical role in cognitive and memory-related processes. The hippocampal formation consists of the dentate gyrus, hippocampus proper, and subiculum, and its importance in the neural circuitry makes it a key anatomic structure to evaluate in neuroimaging studies. Advancements in imaging techniques now allow detailed assessment of hippocampus internal architecture and signal features that has improved identification and characterization of hippocampal abnormalities. This review aims to summarize the neuroimaging features of the hippocampus and its common pathologies. It provides an overview of the hippocampal anatomy on magnetic resonance imaging and discusses how various imaging techniques can be used to assess the hippocampus. The review explores neuroimaging findings related to hippocampal variants (incomplete hippocampal inversion, sulcal remnant and choroidal fissure cysts), and pathologies of neoplastic (astrocytoma and glioma, ganglioglioma, dysembryoplastic neuroepithelial tumor, multinodular and vacuolating neuronal tumor, and metastasis), epileptic (mesial temporal sclerosis and focal cortical dysplasia), neurodegenerative (Alzheimer\'s disease, progressive primary aphasia, and frontotemporal dementia), infectious (Herpes simplex virus and limbic encephalitis), vascular (ischemic stroke, arteriovenous malformation, and cerebral cavernous malformations), and toxic-metabolic (transient global amnesia and opioid-associated amnestic syndrome) etiologies.
摘要:
海马是位于颞叶内侧的复杂结构,在认知和记忆相关过程中起着至关重要的作用。海马结构由齿状回组成,适当的海马,和下丘,它在神经回路中的重要性使其成为神经影像学研究中评估的关键解剖结构。成像技术的进步现在允许对海马内部结构和信号特征进行详细评估,从而改善了海马异常的识别和表征。本文旨在总结海马的神经影像学特征及其常见病理。它概述了磁共振成像的海马解剖结构,并讨论了如何使用各种成像技术来评估海马。该综述探讨了与海马变异相关的神经影像学发现(不完全海马倒置,沟残余物和脉络膜裂隙囊肿),和肿瘤病理(星形细胞瘤和神经胶质瘤,神经节胶质瘤,胚胎发育不良神经上皮肿瘤,多结节和空泡神经元肿瘤,和转移),癫痫(内侧颞叶硬化和局灶性皮质发育不良),神经退行性(阿尔茨海默病,进行性原发性失语症,和额颞叶痴呆),传染性(单纯疱疹病毒和边缘叶脑炎),血管(缺血性中风,动静脉畸形,和脑海绵状畸形),和毒性代谢(短暂性整体健忘症和阿片类药物相关的遗忘综合征)病因。