Department of Neurology, Dizziness Center, Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam, South Korea; Department of Neurology, Seoul National University College of Medicine, Seoul, South Korea.
Department of Neurology, Dizziness Center, Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam, South Korea; Department of Neurology, Seoul National University College of Medicine, Seoul, South Korea.
Prog Brain Res. 2019;249:211-225. doi: 10.1016/bs.pbr.2019.04.012. Epub 2019 May 15.
The central vestibular system operates to precisely estimate the rotational velocity and gravity orientation using the inherently ambiguous information from peripheral vestibular system. Therefore, any lesions disrupting this function can generate positional nystagmus. Central positional nystagmus (CPN) can be classified into the paroxysmal (transient) and persistent forms. The paroxysmal CPN has the features suggesting a semicircular canal origin regarding the latency, duration, and direction of nystagmus. Patients with paroxysmal CPN commonly show several different types of nystagmus classified according to the provoking positioning. The persistent form of CPN mostly appears as downbeat nystagmus while prone or supine, or apogeotropic or geotropic horizontal nystagmus when the head is turned to either side while supine. CPN may be ascribed to erroneous neural processing within the velocity-storage circuit that functions in estimating angular head velocity, gravity direction, and inertia. Paroxysmal CPN appears to be post-rotatory rebound nystagmus due to lesions involving the cerebellar nodulus and uvula. In contrast, persistent CPN may arise from erroneous gravity estimation. The overlap of lesion location responsible for both paroxysmal and persistent CPN may account for the frequent coexistence of both forms of nystagmus in a single patient.
中枢前庭系统利用外周前庭系统固有的模糊信息，精确估计旋转速度和重力方向。因此，任何破坏此功能的病变都会产生位置性眼球震颤。中枢性位置性眼球震颤（CPN）可分为阵发性（短暂性）和持续性两种形式。阵发性 CPN 的潜伏期、持续时间和眼球震颤方向提示其起源于半规管。阵发性 CPN 患者常表现出几种不同类型的眼球震颤，根据诱发的体位进行分类。持续性 CPN 多表现为俯垂性眼球震颤，在仰卧位时出现；或在仰卧位时向一侧转头出现向地性或背地性水平眼球震颤。CPN 可能是由于在估计角头部速度、重力方向和惯性的速度存储回路中出现错误的神经处理所致。阵发性 CPN 似乎是由于小脑小结和绒球病变引起的旋转后反弹眼球震颤。相比之下，持续性 CPN 可能是由于错误的重力估计所致。导致阵发性和持续性 CPN 的病变部位重叠，可能导致单个患者同时存在两种形式的眼球震颤。
