Furman J M, Wall C, Pang D L
Department of Otolaryngology, University of Pittsburgh, PA.
Brain. 1990 Oct;113 ( Pt 5):1425-39. doi: 10.1093/brain/113.5.1425.
The vestibulo-ocular reflex of 4 patients with periodic alternating nystagmus (PAN) was studied in detail. Rotational testing was used to investigate the horizontal semicircular canal-ocular reflex, canal-otolith interaction, and the dynamic otolith-ocular reflex. Results indicated abnormal gain and phase of the horizontal semicircular canal-ocular reflex during sinusoidal rotation and a variable rate of decay of postrotatory responses. Each patient had abnormal canal-otolith interaction. An enlarged modulation component of the dynamic otolith-ocular response was observed in each patient. This study supports the idea that PAN is caused by an instability in the velocity storage element, a hypothetical neural circuit that perseverates the eye movement response to both vestibular and optokinetic stimulation. Further, we postulate that PAN may be caused by lesions of the cerebellar uvula and nodulus or their connections with the brainstem vestibular nuclei.
对4例周期性交替性眼球震颤（PAN）患者的前庭眼反射进行了详细研究。采用旋转测试来研究水平半规管-眼反射、半规管-耳石相互作用以及动态耳石-眼反射。结果表明，在正弦旋转过程中水平半规管-眼反射的增益和相位异常，旋转后反应的衰减率也各不相同。每位患者均存在半规管-耳石相互作用异常。在每位患者中均观察到动态耳石-眼反应的调制成分增大。本研究支持以下观点：PAN是由速度存储元件的不稳定性引起的，速度存储元件是一种假设的神经回路，它会持续保持对前庭和视动刺激的眼球运动反应。此外，我们推测PAN可能是由小脑蚓垂和小结或它们与脑干前庭核的连接受损所致。
